Controlling a network node

Abstract

A network node (2204) is in a wireless communications service provider network (2002) and is communicatively couplable to a device (100) comprising a SIM (102) issued by a wireless communications service provider An authenticated connection is established between the wireless communications service provider network (2202) and the device (100) via a first radio resource of a plurality of radio resources allocated to the wireless communications service provider. An RSS associated with the first radio resource is at least as strong, at the device (100), as an RSS associated with any other radio resource in the plurality of radio resources. A latency test is performed in respect of the authenticated connection. In response to the latency test indicating an acceptable latency of the authenticated connection, the authenticated connection in maintained. In response to the latency test indicating an unacceptable latency of the authenticated connection, the authenticated connection ceases to be used.

Description

[0001] CONTROLLING A NETWORK NODE

[0002] Field

[0003] The present disclosure relates to controlling a network node.

[0004]

[0005] A single-network subscriber identity module (SIM) allows a device to authenticate with, and use services provided by, a single wireless communications service provider network.

[0006] A device comprising a single-network SIM selects a radio resource with which to access the wireless communications service provider network based on signal strength. In particular, the device selects the radio resource with the highest signal strength to access the wireless communications service provider network.

[0007] This enables the device to select a radio resource deterministically and may enable the device to select an objectively best radio resource to use to access the wireless communications service provider network.

[0008] According to first embodiments, there is provided a computer-implemented method of controlling a wireless communications service provider network node, the wireless communications service provider network node being in a wireless communications service provider network and being communicatively couplable to a device comprising a subscriber identity module, SIM, issued by a wireless communications service provider, the wireless communications service provider network being controllable by the wireless communications service provider, the method comprising:

[0009] establishing an authenticated connection between the wireless communications service provider network and the device via a first radio resource of a plurality of radio resources allocated to the wireless communications service provider, a received signal strength associated with the first radio resource being at least as strong, at the device, as a received signal strength associated with any other radio resource in the plurality of radio resources; andperforming a latency test in respect of the authenticated connection, wherein, in response to the latency test indicating an acceptable latency of the authenticated connection, the method comprises maintaining the authenticated connection, and

[0010] wherein, in response to the latency test indicating an unacceptable latency of the authenticated connection, the method comprises ceasing using the authenticated connection.

[0011] According to second embodiments, there is provided a computer-implemented method of controlling a wireless communications service provider network node, the wireless communications service provider network node being in a wireless communications service provider network and being communicatively couplable to a device comprising a subscriber identity module, SIM, issued by a wireless communications service provider, the wireless communications service provider network being controllable by the wireless communications service provider, the method comprising:

[0012] establishing an authenticated connection between the wireless communications service provider network and the device via a first radio resource of a plurality of radio resources allocated to the wireless communications service provider, a received signal strength associated with the first radio resource being at least as strong, at the device, as a received signal strength associated with any other radio resource in the plurality of radio resources,

[0013] wherein, in response to determining that latency of the authenticated connection is acceptable, the method comprises maintainingthe authenticated connection, and wherein, in response to determining that latency of the authenticated connection is unacceptable, the method comprises ceasing usingthe authenticated connection.

[0014] According to third embodiments, there is provided a node configured to perform a method accordingto the first and / or second embodiments.

[0015] According to fourth embodiments, there is provided a computer-implemented method of controlling a device comprising a subscriber identity module, SIM, issued by a wireless communications service provider, the method comprising:

[0016] selecting a first radio resource from a plurality of radio resources allocated to the wireless communications service provider, a received signal strength associated withthe first radio resource being at least as strong, at the device, as a received signal strength associated with any other radio resource in the plurality of radio resources; establishing an authenticated connection with a wireless communications service provider network via the first radio resource, the wireless communications service provider network being controllable by the wireless communications service provider;

[0017] ceasing using the authenticated connection in response to a latency test conducted by a wireless communications service provider network node in the wireless communications service provider network indicating that the authenticated connection has an unacceptable latency;

[0018] selecting a second radio resource from a subset of the plurality of radio resources, the subset of the plurality of radio resources excluding the first radio resource, a received signal strength associated with the second radio resource being less strong, at the device, than the received signal strength associated with the first radio resource;

[0019] establishing a further authenticated connection with the wireless communications service provider network via the second radio resource; and maintainingthe further authenticated connection in response to a further latency test conducted by the wireless communications service provider network node indicatingthatthefurther authenticated connection has an acceptable latency.

[0020] According to fifth embodiments, there is provided a computer-implemented method of controlling a device, the method comprising:

[0021] selecting a radio resource from a set of radio resources, the selected radio resource having the strongest received signal strength amongst a plurality of radio resources allocated to a wireless communications service provider;

[0022] attempting to establish, via the selected radio resource, an authenticated connection having an acceptable latency with a wireless communications service provider network of the wireless communications service provider; and

[0023] in response to the attempt to establish the authenticated connection having the acceptable latency being unsuccessful:

[0024] repeating the selecting and attempting with one or more further radio resources of the set of radio resources until an authenticated connection havingthe acceptable latency has been established, the one or more further radio resources having lower received signal strengths than the selected radio resource.

[0025] Accordingto sixth embodiments, there is provided a device configured to perform a method accordingto the fourth and / or fifth embodiments.

[0026] According to seventh embodiments, there is provided a system comprising a node according to the third embodiments and a device according to the sixth embodiments.

[0027] According to eighth embodiments, there is provided a computer program configured to perform a method according to the first, second, fourth and / or fifth embodiments.

[0028] Brief Description of the Drawings

[0029] Various embodiments will now be described, by way of example only, with reference to the accompanying drawings in which:

[0030] Figure 1 shows a schematic block diagram of an example of a device;

[0031] Figure 2 shows a schematic diagram of an example of a system in a first state; Figure 3 shows a schematic diagram of an example of a data record;

[0032] Figure 4 shows a schematic diagram of another example of a data record;

[0033] Figure 5 shows a schematic diagram of another example of a data record;

[0034] Figure 6 shows a schematic diagram of another example of a data record in a first state;

[0035] Figure 7 shows a schematic diagram of the example system shown in Figure 2 in a second state;

[0036] Figure 8 shows a message flow diagram of an example of a method;

[0037] Figure 9 shows a schematic diagram of the example data record shown in Figure 6 in a second state;

[0038] Figure 10 shows a schematic diagram of the example system shown in Figures 2 and 7 in a third state;

[0039] Figure 11 shows a message flow diagram of another example of a method;

[0040] Figure 12 shows a schematic diagram of the example data record shown in Figures 6 and 9 in a third state;Figure 13 shows a schematic diagram of the example system shown in Figures 2, 7 and 10 in a fourth state;

[0041] Figure 14 shows a message flow diagram of another example of a method;

[0042] Figure 15 shows a schematic diagram of the example data record shown in Figures 6, 9 and 12 in a fourth state;

[0043] Figure 16 shows a schematic diagram of the example system shown in Figures 2, 7, 10, and 13 in a fifth state;

[0044] Figure 17 shows a graph of an example of radio resource allocation;

[0045] Figure 18 shows a graph of another example of radio resource allocation;

[0046] Figure 19 shows a graph of another example of radio resource allocation;

[0047] Figure 20 shows a schematic diagram of another example of a system;

[0048] Figures 21 A and 21 B show a message flow diagram of another example of a method; and

[0049] Figure 22 shows a schematic diagram of another example of a data record.

[0050] Detailed Description

[0051] Various examples will be described below relating to network-based selection. The term “network-based selection” is used herein to mean selection that occurs in a network rather than, for example, at am edge device such as a user device. Such network-based selection may be performed by various types of network node and / or may take various forms, as will be described in more detail below.

[0052] Some examples below relate to selection of a wireless communications service provider network from amongst multiple candidate wireless communications service provider networks. Such examples may be particularly, but not exclusively, effective for devices with multi-network SIMs as will be described in more detail below.

[0053] Some examples below relate to selection of a radio resource amongst multiple candidate radio resources. Such examples may be particularly, but not exclusively, effective for devices with single-network SIMs as will also be described in more detail below.

[0054] Both examples facilitate objectively better selection, whether of a particular wireless communications service provider network and / or of a particular radio resource.

[0055] Indeed, features from both examples may be combined together.For instance, a given wireless communications service provider network may be selectable, for example for a device with a multi-network SIM issued by a wireless communications service provider, from amongst multiple candidate wireless communications service provider networks. The same wireless communications service provider network may also be able to facilitate selection, for example for a device with a single-network SIM issued by the wireless communications service provider, of a radio resource from amongst multiple radio resources allocated to the wireless communications service provider.

[0056] Wireless Communications Service Provider Network Selection

[0057] A multi-network SIM, also known as a “multi-net SIM”, allows a device to authenticate with multiple wireless communications service provider networks to which the SIM has access. Such access may be managed by a network aggregator, which may also be referred to simply as an “aggregator”.

[0058] A network aggregator typically has commercial agreements with a number of wireless communications service providers and allows customers to use any of those wireless communications service providers via a single, multi-network SIM.

[0059] A device comprising a multi-network, steered SIM selects a wireless communications service provider network to authenticate with based on a prioritised list. Such a device selects the highest priority wireless communications service provider network to authenticate with first.

[0060] A device comprising a multi-network, non-steered SIM selects a wireless communications service provider networkto authenticate with based on signal strength. Such a device selects the wireless communications service provider network with the highest signal strength to authenticate with first.

[0061] While such methods enable a device to select a wireless communications service provider network deterministically, there may be an objectively better wireless communications service provider network for the device than the wireless communications service provider network selected using such methods.

[0062] Examples described herein relate generally to wireless communications service provider network selection. In accordance with such examples, wireless communications service provider network selection is not based solely on a prioritisedlist and / or signal strength. In such examples, one or more additional measures are used to select a wireless communications service provider network. For example, authentication time and / or latency may be used as metrics for wireless communications service provider network selection. Latency may also be referred to as “network delay”. Use of such metrics enables an objectively better wireless communications service provider network to be selected. Examples described herein may be implemented by a network node. An example of such a network node is a network aggregator network node, namely a node in a network aggregator network.

[0063] Referring to Figure 1 , there is shown an example of a device 100.

[0064] The device 100 may take various forms. For example, the device 100 may comprise a user device. An example of a user device is a mobile computing device. Examples of mobile computing devices include, but are not limited to, handheld mobile computing devices, laptop computing devices, smart meters, and wearable computing devices. Examples of handheld mobile computing devices include, but are not limited to, smartphones and tablet computing devices. The device 100 may comprise an Internet of Things (loT) device.

[0065] The example device 100 comprises a SIM 102. SIMs can take various forms. For example, a SIM may be provided on a physical SIM card that is inserted into the device 100. Another form of SIM is an embedded SIM, known as an eSIM. An eSIM is embedded in a device. An eSIM may take the form of software installed on an embedded universal integrated circuit card (eUlCC). Other variants of SIM include, but are not limited to, soft SIMs (also known as virtual SIMs (VSIMs)) and integrated SIMs (iSIMs).

[0066] The example device 100 comprises a modem 104. The modem 104 enables the device 100 to communicate wirelessly using the SIM 102. The modem 104 may measure received signal strength on one or more radio resources. The modem 104 may be used to identify the radio resource with the strongest received signal strength. Signal strength measurement may be based upon line-of-sight from a base station to the device 100 and any objects that block line-of-sight. Examples of such objects include, but are not limited to, concrete, trees and atmospherics (such as moisture in the air).

[0067] The example device 100 comprises a software application 106. The software application 106 may be a native software application or may have been installed onto the device 100. The device 100 may comprise one or more such software applications 106.The device 100 may comprise one or more components not shown in Figure 1. Examples of such other components include, but are not limited to, power sources, processors, memory, and input / output interfaces. A processor may execute instructions stored in memory to perform techniques described herein.

[0068] Referring to Figure 2, there is shown an example of a system 200 in a first state. In this example, the system 200 comprises a device 100.

[0069] In this example, the device 100 establishes radio connectivity with a radio access network (RAN) 202 via an air interface 204.

[0070] The RAN 202 may comprise various elements including, but not limited to, base stations (also known as “cell towers”) and base station controllers.

[0071] The air interface 204 provides a set of radio resources. In this example, the radio resources comprise distinct frequency bands. Radio resources may be different in other examples. For example, radio resources may comprise distinct resource blocks (RBs).

[0072] In this example, the air interface 204 comprises three frequency bands, denoted “FB A”, “FB B”, and “FB C”. However, the air interface 204 can comprise a different number of frequency bands in other examples.

[0073] In this example, the system 200 comprises a network aggregator network 206. The network aggregator network 206 is a network that is controlled and operated bya network aggregator. In this example, the network aggregator network 206 comprises a network aggregator node 208. The network aggregator network 206 may comprise more than one network aggregator node 208 in other examples. The network aggregator node 208 may comprise one or more servers. The network aggregator node 208 may be fully or partly virtualised.

[0074] In this example, the system 200 comprises first, second and third wireless communications service provider networks 210, 212, 214. In other examples, the system 200 comprises a different number of wireless communications service provider networks. In general, the system 200 comprises at least two wireless communications service provider networks.

[0075] In this example, each wireless communications service provider network 210, 212, 214 is a network that is controlled and operated by a respective wireless communications service provider. An example of a wireless communications service provider is a mobile network operator (MNO). Another example of a wirelesscommunications service provider is a mobile virtual network operator (MVNO). In examples described herein, the first, second and third wireless communications service provider networks 210, 212, 214 are all MNO networks. However, the first, second and third wireless communications service provider networks 210, 212, 214 may be any combination of MNO, MVNO and / or other wireless communications service provider networks in other examples.

[0076] In this example, the first wireless communications service provider network 210 is a first MNO network 210 that is controlled and operated by a first MNO. In this example, the first MNO network 210 comprises an authentication node 216. In this example, the first MNO network 210 comprises a latency testing node 218. The authentication node 216 is responsible for authentication in the first MNO network 210 and will be described in more detail below. The latency testing node 218 is involved in latency tests relating to the first MNO network 210 and will also be described in more detail below. Although the authentication and latency testing nodes 216, 218 are shown as separate entities in Figure 2, their functionality may be combined into a single node in other examples. The authentication and latency testing nodes 216, 218 may comprise one or more servers. The authentication and latency testing nodes 216, 218 may be fully or partly virtualised.

[0077] In this example, the second wireless communications service provider network 212 is a second MNO network 212 that is controlled and operated by a second MNO. In this example, the second MNO network 210 comprises an authentication node 220 and a latency testing node 222. In this example, the authentication and latency testing nodes 220, 222 have the same functionality as the authentication and latency testing nodes 216, 218, except that they relate to the second MNO network 210. The authentication and latency testing nodes 220, 222 may comprise one or more servers. The authentication and latency testing nodes 220, 222 may be fully or partly virtualised.

[0078] In this example, the third wireless communications service provider network 214 is a third MNO network 214 that is controlled and operated by a third MNO. In this example, the third MNO network 214 comprises an authentication node 224 and a latency testing node 226. In this example, the authentication and latency testing nodes 224, 226 have the same functionality as the authentication and latency testing nodes 216, 218 and the authentication and latency testing nodes 220, 222, except that they relate to the third MNO network 214. The authentication and latency testing nodes 224,226 may comprise one or more servers. The authentication and latency testing nodes 224, 226 may be fully or partly virtualised.

[0079] In this example, the device 100 is communicatively couplable with the network aggregator network 206 via the RAN 202 and the air interface 204. The term “communicatively couplable” is used herein in relation to multiple entities to mean that those entities can be communicatively coupled to each other even if they are not currently communicatively coupled. The network aggregator network 206 is communicatively couplable with each of the first, second, and third MNO networks 210, 212, 214, for example by one or more private networks.

[0080] The network aggregator network 206, the first MNO network 210, the second MNO network 212 and / or the third MNO network 214 may be referred to as a “core network” (ON). The network aggregator network 206 may be referred to as an “ingress network”.

[0081] In examples, the device 100 can access the network aggregator network 206 via any of the three frequency bands, FB A, FB B, FB C even if the SIM 102 has not been authenticated to any of the first, second, and third MNO networks 210, 212, 214.

[0082] Referring to Figure 3, there is shown an example of a data record 300.

[0083] In this example, the data record 300 is shown in the form of a table. However, the data record 300 may take other forms in other examples.

[0084] In this example, a first column of the data record 300 represents a frequency band of the air interface 204 between the device 100 and the RAN 202.

[0085] In this example, a second column of the data record 300 represents a priority of the corresponding frequency band. In this example, a lower number in the second column corresponds to a higher priority and vice versa.

[0086] In this specific example, the highest priority frequency band, having a priority of “1 ” is FB B, the lowest-priority frequency band, having a priority of “3” is FB A, and FB C has a medium-level priority indicated by priority number “2”.

[0087] Such a data record 300 may be stored in a multi-network, steered SIM 102 and / or elsewhere on the device 100.

[0088] The prioritisation order may be set by the network aggregator or otherwise. The prioritisation order may change over time.

[0089] Referring to Figure 4, there is shown another example of a data record 400.In this example, the data record 400 is shown in the form of a table. However, the data record 400 may take other forms in other examples.

[0090] In this example, a first column of the data record 400 represents a frequency band of the air interface 204 between the device 100 and the RAN 202.

[0091] In this example, a second column of the data record 400 represents a received signal strength (RSS) rank of the corresponding frequency band. In this example, a lower number in the second column corresponds to a higher RSS. As explained above, the RSS of a given frequency band may be determined using the modem 104 of the device 100.

[0092] In this specific example, the highest RSS frequency band, having an RSS rank of “1 ” is FB B, the lowest-RSS frequency band, having an RSS rank of “3” is FB A, and FB C has a medium-level RSS rank indicated by RSS rank number “2”.

[0093] In this example, the frequency band ranking order represented in the data record 400 corresponds to the frequency band prioritisation order represented in the data record 300. However, the ordering could be different in other examples.

[0094] Such a data record 400 may be stored in a multi-network, non-steered SIM 102 and / or elsewhere on the device 100.

[0095] Although, in this example, the second column of the data record 400 indicates RSS rank, the second column of the data record 400 may include other data indicative of signal strength and / or relative signal strength in other examples. For example, the second column of the data record 400 may include measured RSS values. RSS may be measured in decibels per milliwatt (dBm). Thus, the RSS values may be recorded in the data record 400, and the RSS values may be compared to each other to identify the relative RSS ranks.

[0096] The RSS rank order may change over time, for example as a result of changing radio conditions between the device 100 and the RAN 202.

[0097] Referring to Figure 5, there is shown another example of a data record 500.

[0098] In this example, the data record 500 is shown in the form of a table. However, the data record 500 may take other forms in other examples.

[0099] In this example, a first column of the data record 500 represents a frequency band of the air interface 204 between the device 100 and the RAN 202.

[0100] In this example, a second column of the data record 500 represents an MNO associated with the corresponding frequency band. An MNO may be associated with afrequency band by having been allocated thatfrequency band, for example by a regulator or government.

[0101] In this specific example, the first frequency band, FB A, is associated with the first MNO, the second frequency band, FB B, is associated with the third MNO, and the third frequency band, FB C, is associated with the second MNO.

[0102] In this example, the data record 500 therefore maps frequency bands to corresponding MNOs and vice versa.

[0103] Such a data record 500 may be accessible to the network aggregator network 206. For example, the network aggregator node 208 may store the data record 500, the data record 500 may be stored by another entity in the network aggregator network 206, or otherwise.

[0104] The data record 500 may be updated. For example, frequency band allocation may change over time, and such changes may be reflected in the data record 500.

[0105] Referringto Figure 6, there is shown another example of a data record 600 in a first state.

[0106] In this example, the data record 600 is shown in the form of a table. However, the data record 600 may take other forms in other examples. Although shown as a single data record 600 in this example, the information in the data record 600 may be split across multiple data records in other examples.

[0107] In this example, a first column of the data record 600 represents an MNO. In this example, a second column of the data record 600 represents a recorded authentication time. In this example, a third column of the data record 600 represents an authentication time threshold. In this example, a fourth column of the data record 600 represents an authentication result. In this example, a fifth column of the data record 600 represents a recorded latency. In this example, a sixth column of the data record 600 represents a latency threshold. In this example, a seventh column of the data record 600 represents a latency test result.

[0108] In this specific example, the data record 600 is pre-populated with an example authentication time threshold of 4 seconds. However, a different authentication time threshold may be used in other examples. In some examples, the authentication time threshold is a value from 1 to 4 seconds. The authentication time threshold may bereferred to as an “authentication timeout”, an “authentication timeout limit”, a “threshold authentication time”, or the like.

[0109] In this specific example, the authentication time thresholds are the same for all MNOs. This enables all MNOs to be assessed equally in terms of authentication time performance. In other examples, different authentication time thresholds may be used for different MNOs.

[0110] In this specific example, the data record 600 is pre-populated with an example latency threshold of 50 milliseconds. However, a different latency threshold maybe used in other examples. The latency threshold may be referred to as a “latency timeout”, a “latency timeout limit”, a “threshold latency”, or the like.

[0111] In this specific example, the latency thresholds are the same for all MNOs. This enables all MNOs to be assessed equally in terms of latency performance. In other examples, different latency thresholds may be used for different MNOs.

[0112] The data record 600 may represent the state of the data record 600 before MNO selection has been performed.

[0113] In this specific example, the data record 600 indicates both authentication results and latency test results. In this example, the authentication and latency test results are recorded as “pass” or “fail”. However, the authentication and latency test results may be recorded using a one-bit flag in another example, for instance with a value of “1 ” being used for a pass, and value of “0” being used for a fail. However, one or both of these items may be omitted in other examples. For instance, an entity accessing the data record 600 may compare, for example, a recorded authentication time against an authentication time threshold and determine, based on that comparison, whether the corresponding authentication result is a pass or fail. Such an on-the-fly determination may reduce the amount of data stored in the data record 600.

[0114] Referring to Figure 7, there is shown another example of a system 700.

[0115] The example system 700 corresponds generally to the example system 200, but in a second state. However, and as will be explained with reference to Figures, the device 100 selects the second frequency band, FB B, to access the network aggregator network 206, and the network aggregator network 206 performs a procedure with the third MNO network 214 based on an association between the second frequency band, FB B, and the third MNO network 214.Referring to Figure 8, there is shown an example of a method 800 of selecting an MNO network.

[0116] At item 802, the device 100 selects a radio resource on which to access the network aggregator network 206. The device 100 may select the radio resource in various ways, such as described above. For example, if the device 100 comprises a multinetwork, steered SIM 102, the device 100 may use a data record such as the example data record 300 to select a highest priority frequency band. If the device 100 comprises a multi-network, non-steered SIM 102, the device 100 may use the modem 104 to identify the frequency band with the highest RSS and select the highest RSS frequency band accordingly. Alternatively, the device 100 may use a data record such as the example data record 400 to select a highest RSS frequency band. In this specific example, the device 100 selects the second frequency band, FB B.

[0117] At item 804, the device 100 accesses the network aggregator network 206 via the second frequency band, FB B. The device 100 may access the network aggregator network 206 using an access point name (APN) of the network aggregator network 206. The APN may be stored on the SIM 102 or otherwise. The APN may be a private APN, where the private APN is private to the device 100, SIM 102, and / or customer.

[0118] In this example, the device 100 accesses the network aggregator network by transmitting an access request via the selected radio resource, which in this example is the second frequency band, FB B. Accessing the network aggregator network 206 in this manner may involve the device 100 issuing a User Request message. The device 100 may issue the User Request message by sending the User Request message to the network aggregator network 206. The User Request message may be triggered by a specific application on the device 100, for example the application 106, or otherwise. For example, the User Request message may correspond to a request made by a user application to access a cellular network. Receipt of the User Request message by the network aggregator network 206 may trigger one or more procedures as described below.

[0119] At item 806, the network aggregator network 206 identifies the MNO associated with the second frequency band, FB B. In this specific example, the MNO associated with the second frequency band, FB B, is the third MNO. The network aggregator network 206 may identify the MNO in various ways. For example, the network aggregator network 206 may use a data record such as the example data record 500 to map the frequency bandvia which the device 100 has accessed the network aggregator network 206 to the corresponding MNO. In particular, the example data record 500 maps the second frequency band, FB B, to the third MNO.

[0120] At item 808, the network aggregator network 206 attempts to authenticate the SIM 102 with the third MNO network 214. This may involve the network aggregator network 206 sending one or more authentication credentials associated with the SIM 102 to the third MNO network 214 and awaiting an authentication result. The network aggregator network 206 may already have the one or more authentication credentials for the SIM 102 and / or may obtain the one or more authentication credentials from the device 100 to attempt authentication.

[0121] In this example, the network aggregator network 206 starts an authentication timer on initiating the authentication procedure with the third MNO network 214. In this example, the network aggregator network 206 stops the authentication timer in response to an authentication timer stop trigger. An example of an authentication timer stop trigger is successful authentication of the SIM 102 with the third MNO network 214. Another example of an authentication timer stop is an elapsed time on the authentication timer reachingthe authentication time threshold.

[0122] In this specific example, the authentication procedure completes successfully in that the third MNO network 214 validates the authentication credentials provided by the network aggregator network 206 and informs the network aggregator network 206 accordingly. In this example, the network aggregator network 206 records the authentication time, namely the time taken between starting and successfully completing the authentication procedure. In this specific example, the authentication time is 5 seconds.

[0123] In this example, the network aggregator network 206 compares the recorded authentication time with the authentication time threshold. As explained above, an authentication time threshold may be stored in a data record, such as the data record 600. In this specific example, the authentication time threshold is 4 seconds. However, the authentication time threshold can be different in other examples.

[0124] In this example, since the recorded authentication time (5 seconds) is longer than the authentication time threshold (4 seconds), the authentication result is “fail”. In this example, the authentication result is “fail” even though the network aggregator network206 eventually authenticated the SIM 102 with the third MNO network 214. Alternatively, or additionally, failure of the authentication procedure may comprise rejection of the authentication credentials provided by the network aggregator 206.

[0125] At item 810, the network aggregator network 206 causes access between the device 100 and the network aggregator network 206 via the second frequency band, FB B, to terminate. For example, the network aggregator network 206 may transmit a termination message to the device 100 to cause the device 100 to terminate such access. The termination message may cause the device 100 to terminate such access by causing the device 100 to release the connection with the network aggregator network 206 via the second frequency band, FB B. Such a message may or may not indicate a reason for the termination. An example of such a message is an attention command, which may be known as an “AT command”.

[0126] In this example, the network aggregator network 206 records the authentication time even though the authentication time exceeded the authentication time threshold.

[0127] In some examples, the network aggregator network 206 records the authentication procedure as “fail” unless the authentication procedure successfully completes within the authentication time threshold. In such examples, the network aggregator network 206 may terminate the authentication process if the authentication procedure has not successfully completed within the authentication time threshold. In some examples, the network aggregator network 206 only records the authentication time if the authentication procedure successfully completes within the authentication time threshold.

[0128] Referring to Figure 9, there is shown another example of a data record 900.

[0129] The example data record 900 corresponds to the example data record 600 but populated with data resulting from the procedure described above with reference to Figures 7 and 8 and, hence, in a second state.

[0130] In particular, the example data record 900 indicates that the authentication with the third MNO network 214 failed, since the authentication procedure did not successfully complete within the authentication time threshold. In this example, the data record 900 indicates the recorded authentication time of 5 seconds.

[0131] Referring to Figure 10, there is shown another example of a system 1000.The example system 1000 corresponds generally to the example system 700, but in a third state. However, and as will be explained with reference to Figure 11 , the device 100 selects the third frequency band, FB C, to access the network aggregator network 206, and the network aggregator network 206 performs various test procedures with the second MNO network 212 based on an association between the third frequency band, FB C, and the second MNO network 212. As will also be explained with reference to Figure 11 , the device 100 was not able to select the second frequency band, FB B, to use for accessing the network aggregator network 202 in this scenario. For example, the device 100 may have been blocked from selectingthe second frequency band, FB B. This is because the authentication procedure based on the second frequency band, FB B, and the third MNO network 214 just failed and is therefore unlikely to success in this scenario.

[0132] Referring to Figure 11, there is shown another example of a method 1100 of selecting an MNO network. The example method 1100 may follow the example method 800.

[0133] At item 1102, the device 100 select another radio resource on which to access the network aggregator network 206. At item 1102, the device 100 is unable to select the second frequency band, FB B, that was selected at item 802. This is depicted in Figure 10 with an “X” in place of “FB B”. The device 100 is unable to select the second frequency band, FB B, since the authentication procedure based on the second frequency band, FB B, failed at item 810 and is therefore unlikely to succeed at this stage.

[0134] The device 100 may select the additional radio resource in various ways. For example, if the device 100 comprises a multi- network, steered SIM 102, the device 100 may use a data record such as the example data record 300 to select the second-highest priority frequency band. If the device 100 comprises a multi-network, non-steered SIM 102, the device 100 may use the modem 104 to identify the remaining frequency band with the highest RSS and select that frequency band accordingly. Alternatively, the device 100 may identify the remaining frequency band with the highest RSS from a data record such as the data record 400. In this specific example, the device 100 selects the third frequency band FB C.

[0135] At item 1104, the device 100 accesses the network aggregator network 206 via the selected radio resource, namely the third frequency band, FB C.At item 1106, the network aggregator network 206 identifies the MNO associated with the third frequency band, FB C, for example using a data record such as the example data record 500. In this specific example, the MNO associated with third frequency band, FB C, is the second MNO.

[0136] At item 1108, the network aggregator network 206 attempts to authenticate the SIM 102 with the second MNO network212.

[0137] In this specific example, the authentication procedure completes successfully. In this example, the network aggregator network 206 records the authentication time. In this specific example, the authentication time is 2 seconds.

[0138] In this example, the network aggregator network 206 compares the recorded authentication time with the authentication time threshold. In this example, since the recorded authentication time (2 seconds) is shorter than the authentication time threshold (4 seconds), the authentication result is “pass”.

[0139] Thus, the network aggregator network 206 has authenticated the SIM 102 with the second MNO network 212 in an acceptable authentication time.

[0140] At item 1110, the network aggregator network 206 initiates a latency test. A latency test may involve measuring the amount of time taken to transmit a data message from one point to an endpoint. Both points may, for example, be in a cellular network. The latency test may involve sending an echo request (also known as a “ping”) and measuring the lapse in time to receiving an echo response in response to the echo request. An example of an echo request is an Internet Control Message Protocol (ICMP) echo request, and an example of an echo response is an ICMP echo response. The measured time lapse is indicative of the speed at which the data message was sent, reached the endpoint, and was then sent back to the original source. The latency test may, alternatively or additionally, involve a Traceroute test. A Traceroute test is similar to an ICMP ping test. However, a Traceroute test adds additional information on routing. A Traceroute test might provide a greater level of detail, relative to ICMP pings, for information that may be used and / or displayed. However, ICMP pings may provide a more straightforward mechanism to test and measure latency than Traceroute tests. ICMP pinging and Traceroute may be referred to collectively as “diagnostics tools”, “network tools”, or “network diagnostics tools”. Latency may be measured in any unit oftime, such as nanoseconds or milliseconds. Latency may therefore correspond to speed of return.

[0141] An echo request traverses a network from its point of origin to its target destination. The network may be under capacity, at capacity, or over capacity. The capacity level of a network dictates speed of data communication in the network. Such data communication may also be referred to as “flow” or “traffic”.

[0142] The combination of capacity of a network and signal strength dictates the speed at which the echo request returns to its origin after being sent. The capacity may be based on bandwidth and amount of traffic. A network may be considered “free-flowing” when the amount of traffic on the network is significantly below the bandwidth. A strong signal may indicate a fast connection, and a weak signal may indicate a slow connection.

[0143] In this example, the latency test is in respect of a communication channel between the device 100 and the second MNO network212. The communication channel may comprise a communication channel leg between the network aggregator network 206 and the device 100 and another communication channel leg between the network aggregator network 206 and the second MNO network 212. The network aggregator network 206 may, in effect, bridge the two communication channel legs.

[0144] The network aggregator network 206 may transmit an echo request to the latency testing node 222 in the second MNO network 212 and may await an echo response from the latency testing node 222 in the second MNO network 212 in response to the echo request. The network aggregator network 206 may address the echo request to a known network identifier of the latency testing node 222 in the second MNO network 212. The network identifier may be an Internet Protocol (IP) address, or otherwise.

[0145] In this example, the network aggregator network 206 receives the echo response, and records the time interval between transmitting the echo request and receiving the echo request as the latency between the network aggregator network 206 and the second MNO network 212. For example, the network aggregator network 206 may store the transmission time of the echo request, and may use a difference between the transmission time of the echo request and a reception time of the echo response as the time interval. The echo request and the echo response may share a common identifier and may be correlated accordingly. The transmission time, reception time and / or time interval may be stored even after the time interval has been determined. Such data maybe used to determine and / or predict one or more network metrics based on previous latency tests. Although that time interval is referred to herein as a “latency”, the time interval may instead be referred to as a “response time”. In particular, the term “latency” may be used to indicate the time to transmit data from one entity to another, and the term “response time” may be used to indicate the total round-trip time taken to receive a response after sending a request.

[0146] At item 1112, the network aggregator network 206 initiates a latency test with the device 100. For example, the network aggregator network 206 may transmit an echo request to the device 100 and may await an echo response from the device 100 in response to the echo request. The network aggregator network 206 may address the echo request to a known network identifier of the device 100. The network identifier may be an IP address, or otherwise.

[0147] In this example, the network aggregator network 206 receives the echo response, and records the time interval between transmitting the echo request to the device 100 and receiving the echo response from the device 100 as the latency between the network aggregator network 206 and the device 100.

[0148] In this example, the network aggregator network 206 adds the recorded latency between the network aggregator network 206 and the second MNO network 212 and the recorded latency between the network aggregator network 206 and the device 100 together and records the result as the end-to-end latency between the device 100 and the second MNO network 212.

[0149] In this specific example, the end-to-end latency is recorded as 100 milliseconds. In this example, the network aggregator network 206 compares the recorded latency with the latency threshold.

[0150] In this example, since the recorded latency (100 milliseconds) is longer than the latency threshold (50 milliseconds), the latency test result is “fail”. In this example, the latency test result is “fail” even though the network aggregator network 206 eventually received the echo responses from the second MNO network 212 and the device 100.

[0151] At item 1114, the network aggregator network 206 causes the access between the device 100 and the network aggregator network 206 via the third frequency band, FB C, to terminate.In this example, the network aggregator network 206 records the end-to-end latency, even though the latency test was a “fail”. In other examples, the network aggregator network 206 only records the end-to-end latency if the latency test is a “pass”. The network aggregator network 206 may, alternatively or additionally, record the latency between the network aggregator network 206 and the second MNO network 212 and / or may record the latency between the network aggregator network 206 and the device 100.

[0152] In this specific example, the latency test with the second MNO network 212 takes place before the latency test with the device 100. However, the latency tests may take place at the same time or in the reverse order in other examples.

[0153] In some examples, one of the latency tests is only performed if the other latency test is successful. For example, latency between the network aggregator network 206 and the second MNO network 212 may be tested initially. The recorded latency between the network aggregator network 206 and the second MNO network 212 may be compared to a first latency threshold. If the recorded latency is below the first latency threshold, then latency between the network aggregator network 206 and the device 100 may subsequently be tested. The recorded latency between the network aggregator network 206 and the device 100 may then be compared to a second latency threshold. The first and second latency thresholds may be the same as each other or may be different from each other. If the recorded latency is below the second latency threshold, then the latency test result may be “pass”. A two-stage latency test may reduce the amount of data being communicated for latency test purposes. This is because test data is not communicated in the second stage if the first stage is a “fail”. Alternatively, and as explained above, the latency between the network aggregator network 206 and the second MNO network 212 and the latency between the network aggregator network 206 and the device 100 may be summed together and compared to an overall end-to-end latency threshold.

[0154] In this example, an entity or function in the network aggregator network 206 initiates the echo requests, and the echo responses return to the point of origin, namely the entity or function in the network aggregator network 206. In this example, the device 100 does not initiate the echo request.Additionally, in this example, the entity or function in the network aggregator network 206 determines the time taken to receive the echo response and, therefore, the degree of latency that the MNO network to which the SIM 102 is authenticated atthetime of testing (in this example, the second MNO network 212) is experiencing.

[0155] By initiating the echo request from the entity or function in the network aggregator network 206, any MNO network can be compared to one or more thresholds and / or to another MNO network. A low-latency (in other words, fast) MNO network may then be selected. The SIM 102 may, in effect, be forced to authenticate to a low-latency MNO network. This may be managed and / or enforced at a ON and / or ingress network level.

[0156] Referring to Figure 12, there is shown another example of a data record 1200. The example data record 1200 corresponds to the example data record 900, populated with data resulting from the procedure described above with reference to Figures 10 and 11 and, hence, in a third state.

[0157] In particular, the example data record 1200 indicates that the authentication with the second MNO was a “pass”, but that the latency test with the second MNO was a “fail”. In this example, the data record 1200 indicates the recorded authentication time of 2 seconds and the end-to-end latency of 100 milliseconds.

[0158] Referring to Figure 13, there is shown another example of a system 1300.

[0159] The example system 1300 corresponds generally to the example system 1000 in a fourth state. However, and as will be explained with reference to Figure 14, the device 100 selects the first frequency band, FB A, to access the network aggregator network 202, and the network aggregator network 202 performs various test procedures with the first MNO network 210 based on an association between the first frequency band, FB A, and the first MNO network 210. As will also be explained with reference to Figure 14, the device 100 was not able to select the second or third frequency bands, FB B and FB C, to use for accessing the network aggregator network 202 in this scenario. This is because the authentication procedure based on the second frequency band, FB B, and the third MNO previously failed, and because the latency test procedure based on the third frequency band, FB C, and the second MNO also just failed.

[0160] Referring to Figure 14, there is shown another example of a method 1400 of selecting an MNO network. The example method 1400 may follow the example method 1100.At item 1402, the device 100 selects another radio resource on which to access the network aggregator network 206. At item 1402, the device 100 is unable to select the second frequency band, FB B, that was selected at item 802, or the third frequency band, FB C, that was selected at item 1102. This is depicted in Figure 13 with an “X” in place of “FB B” and “FB C”. The device 100 is unable to select the second and third frequency bands, FB B and FB C, since the authentication procedure based on the second frequency band, FB B, failed and since the latency test procedure based on the third frequency band, FB C, also failed. The authentication procedure and latency test are therefore unlikely to succeed at this stage.

[0161] The device 100 may select the additional radio resource in various ways. For example, if the device 100 comprises a multi- network, steered SIM 102, the device 100 may use a data record such as the example data record 300 to select the third-highest priority frequency band. If the device 100 comprises a multi-network, non-steered SIM 102, the device 100 may use the modem 104 to identify the remaining frequency band with the highest RSS and select that frequency band accordingly. Alternatively, the device 100 may identify the remaining frequency band with the highest RSS from a data record such as the data record 400. In this specific example, the device 100 selects the first frequency band, FB A.

[0162] At item 1404, the device 100 accesses the network aggregator network 206 via the selected radio resource, namely the first frequency band, FB A.

[0163] At item 1406, the network aggregator network 206 identifies the MNO associated with the first frequency band, FB A. In this specific example, the MNO associated with the first frequency band, FB A, is the first MNO.

[0164] At item 1408, the network aggregator network 206 attempts to authenticate the SIM 102 with the first MNO network 210. This may involve the network aggregator network 206 sending one or more authentication credentials to the first MNO network 210 and awaiting an authentication result.

[0165] In this specific example, the authentication procedure completes successfully. In this example, the network aggregator network 206 records the authentication time. In this specific example, the authentication time is 3 seconds.

[0166] In this example, the network aggregator network 206 compares the recorded authentication time with the authentication time threshold. In this example, since therecorded authentication time (3 seconds) is shorter than the authentication time threshold (4 seconds), the authentication result is a “pass”.

[0167] Thus, the network aggregator network 206 has authenticated the SIM 102 with the first MNO network 210 in an acceptable authentication time.

[0168] At items 1410 and 1412, the network aggregator network 206 initiates latency tests with the first MNO network 210 and with the device 100 respectively.

[0169] In this specific example, the end-to-end latency is recorded as 30 milliseconds. In this example, the network aggregator network 206 compares the recorded latency with the latency threshold. In this example, since the recorded latency (30 milliseconds) is shorter than the threshold authentication (50 milliseconds), the latency test result is a “pass”.

[0170] At item 1414, an authenticated connection is established between the device 100 and the first MNO network 210. In particular, the network aggregator network 206 does not cause the access between the device 100 and the network aggregator network 206 via the first frequency band, FB A, to terminate.

[0171] In this example, the network aggregator network 206 records the authentication time and the latency.

[0172] In this specific example, the authentication procedure and latency test with the first MNO network 210 were both a “pass” and an authenticated connection was established between the device 100 and the first MNO network 210 at item 1414. If, however, the authentication procedure or the latency test had failed, a different action would have been performed. For example, the network aggregator network 206 may have caused the access between the device 100 and the network aggregator network 206 via the first frequency band, FB A, to terminate. The device 100 would then have accessed the network aggregator network 206 via each of the three available frequency bands, FB A, FB B, FB C, without an authenticated connection having been established between the device 100 and any of the first, second and third MNO networks 210, 212, 214. In such a situation, the device 100 may restart the procedures described herein. In particular, the device 100 may be able to select from any of the three available frequency bands, FB A, FB B, FB C again, for example based on a prioritised list and / or RSS rank.In response to no authenticated connection being established with any of the first, second and third MNO networks 210,212, 214, one or more thresholds may be modified.

[0173] For example, the authentication time threshold may be modified. Such modification may involve increasing the authentication time threshold. For example, the authentication time threshold may be increased from 4 seconds to 5 seconds. This relaxes the authentication time test procedure. The authentication time threshold may be decreased in other examples. For example, as networks develop, average authentication time thresholds may decrease in parity. Decreasing the authentication time threshold may therefore account for networks becoming more efficient. The authentication time thresholds may all be modified by the same amount as each other, or different authentication time thresholds may be used for different MNOs.

[0174] Alternatively, or additionally, the latency threshold may be modified. Such modification may involve increasing the latency threshold. For example, the latency threshold may be increased from 50 milliseconds to 100 milliseconds. This relaxes the latency test procedure. The latency threshold may be decreased in other examples. The latency thresholds may all be modified by the same amount as each other, or different latency thresholds may be used for different MNOs.

[0175] Such threshold modification may be determined by the network aggregator network 206 and may be communicated to the device 100. Alternatively, such modification may be determined by the device 100, for example without instruction from the network aggregator network 206. For instance, the device 100 may be preconfigured to increase the authentication time threshold and / or latency threshold by a predetermined amount with each new cycle.

[0176] Referring to Figure 15, there is shown another example of a data record 1500. The example data record 1500 corresponds to the example data record 1200, populated with data resulting from the procedure described above with reference to Figures 13 and 14 and, hence, in a fourth state.

[0177] In particular, the example data record 1500 indicates that the authentication and latency test with the first MNO network 210 were a “pass”. In this example, the data record 1500 indicates the recorded authentication time of 3 seconds and the recorded end-to-end latency of 30 milliseconds.Referring to Figure 16, there is shown another example of a system 1600.

[0178] The example system 1600 corresponds generally to the example system 1300 in a fifth state. However, Figure 16 shows an authenticated connection 1602 established between the device 100 and the first MNO network 210.

[0179] Data may be communicated to and / or from the device 100 via the authenticated connection 1602. Once the authenticated connection 1602 has been established, the first MNO network 210 may establish a route between the first MNO network 210 and the device 100 for mobile-originating (MO) and / or mobile-terminating (MT) transfers via the RAN 202 and the SIM 102. Such routing may use one or more routing identifiers. Examples of such routing identifiers include, but are not limited to, Mobile Network Code (MNC), International Mobile Subscriber Identity (I MSI), Integrated Circuit Card Identifier (ICCID), a fixed IP address, and a base station identifier.

[0180] The network aggregator network 206 may perform one or more further procedures with an MNO network with which a device 100 has an established communication channel and / or with one or more other MNO networks.

[0181] For example, the network aggregator network 206 may perform one or more further procedures with the first MNO network 210 following the establishment of the authenticated connection 1602 between the device 100 and the first MNO network 210. An example of such a procedure is a latency test.

[0182] Alternatively, or additionally, the network aggregator network 206 may perform one or more procedures with the second and / or third MNO network 212, 214 following the establishment of the authenticated connection 1602 between the device 100 and the first MNO network 210. For example, a latency test performed with the second and / or third MNO network 212, 214 may indicate a very low-latency connection to the second and / or third MNO network 212, 214. The network aggregator network 206 may determine whether or not to try to establish an authenticated connection between the device 100 and the second and / or third MNO network212, 214 in such a situation.

[0183] The one or more procedures may be triggered by one or more procedure triggers. An example of such a procedure trigger is expiry of a predetermined amount of time since a previous procedure. Thus, a procedure may be performed periodically. For example, the predetermined amount of time may be set as one hour. Another example of such a procedure trigger is receipt of a predetermined number of User Requests from the device100 via the authenticated connection 1602. Another example of such a procedure trigger is communication of a predetermined amount of data with the device 100 via the authenticated connection 1602. Where the procedure is a latency test, the procedure trigger may be referred to as a “latency retest trigger”.

[0184] Thus, a given wireless communications service provider may be selected from amongst a plurality of wireless communications service providers associated with a multi-network SIM 102 in response to: (a) successfully authenticating the multi-network SIM 102 with the given wireless communications service provider in less than an authentication time threshold; and (b) determining that a latency between (i) a device 100 comprising the multi-network SIM 102 and (ii) a wireless communications service provider network of the given wireless communications service provider is less than a latency threshold. An authenticated connection 1602 may be established between the device 100 and the wireless communications service provider network.

[0185] Additionally, a given wireless communications service provider may be selected in preference to any other wireless communications service provider in a plurality of wireless communications service providers associated with a multi-network SIM 102 in response to: (a) successfully authenticating the multi-network SIM 102 with the given wireless communications service provider; and (b) successfully completing a latency test between a wireless communications service provider network of the given wireless communications service provider and a device 100 comprising the multi-network SIM 102. The given wireless communications service provider may be selected even if a latency between a wireless communications service provider network of another wireless communications service provider in the plurality of wireless communications service providers and the device 100 comprising the multi-network SIM 102 is lower than a latency between the wireless communications service provider network of the given wireless communications service provider and the device 100 comprising the multinetwork SIM 102.

[0186] Further, a device 100 comprising a multi-network SIM 102 may be controlled as follows: (a) a first radio resource is selected from a set of radio resources available to the multi-network SIM 102; (b) a first access request is transmitted to a network node via the first radio resource, the network node being communicatively couplable to the device 100 and to a plurality of wireless communications service providers; (c) use of the firstradio resource ceases in response to a trigger event; (d) a second radio resource is selected from a subset of the set of radio resources, the subset of the set of radio resources excluding the first radio resource; and (e) a second access request is transmitted to the network node via the second radio resource. The trigger event may comprise receiving a predetermined message from the network node, or otherwise. The subset of the set of radio resources contains fewer radio resources than the set of radio resources and excludes the first radio resource.

[0187] Additionally, a device 100 may be controlled as follows: (a) a radio resource is selected from a set of radio resources; (b) an attempt is made to establish an authenticated connection 1602 meeting one or more target criteria via the selected radio resource; and (c) in response to the attempt to establish the authenticated connection 1602 via the selected radio resource being unsuccessful: the selecting and attempting are repeated with one or more further radio resource of the set of radio resources until an authenticated connection 1602 meeting the one or more target criteria has been established. Examples of such target criteria include, but are not limited to, a successful authentication procedure and a successful latency test.

[0188] Thus, and by way of a summary, an authentication attempt may be performed with a first-selected MNO using an authentication timeout limit. If authentication has not been completed with the first-selected MNO within the authentication timeout limit, a timeout occurs. An authentication attempt is then performed with a second-selected MNO. This procedure repeats until successful authentication has taken place. Following successful authentication, a ping test is completed to ratify an MNO network with which authentication has succeeded. Further if the device 100 has a multi-network, steered SIM 102, is power-cycled, and the SIM 102 comes back online, the network aggregator network 206 may automatically attempt to authenticate and test for latency based upon the network aggregator’s preference of which MNO to authenticate and perform a latency test with first. Thus, the network aggregator network 206 may force selection of the fastest network always first.

[0189] Examples described herein are designed to limit the amount of data communicated for latency test purposes to manage network congestion. By way of an example, an ICMP latency test may involve 64 kilobytes of data at 512 bits per second as standard. Assuming a twelve-hour testing period five days a week, with a sixty-minuteping rate, an estimated monthly data consumption used for the ICMP latency tests is around 3.75 megabytes. In some examples, latency tests are only performed for SIMs 102 that are accessing the network aggregator network 206. For example, latency tests may not be performed for devices that are turned off. This may also help manage network congestion.

[0190] Various metrics may be recorded and may be made available as a result of the procedures described herein. In particular, the network aggregator may make at least some of the metrics available in a Connectivity Management Portal (CMP). For example, the recorded authentication and latency test times may be made available to and by the network aggregator in this manner. This may substantiate the MNO selection process. This may also assist increase efficiency for customers, enable users to be better informed, facilitate validating the choice of the selected MNO, assist in fault-finding, and / or support the network aggregator’s customers. Additionally, support tickets from customers to the network aggregator may be reduced, since the customer is better informed of their own SIM estate.

[0191] As explained above, a Traceroute test may be performed. This may enable an additional level of detail to be displayed from latency test results. Such information may be provided via a portal, such as the CMP. Such information may assist with troubleshooting and / or substantiation of authentication, response, and / or latency times.

[0192] Examples may provide automatic cellular connectivity authentication for any multi-network, non-steered SIM. Examples may prioritise and allocate the fastest MNO network always first to the proximityof any variant of a cellular SIM card. This may enable the best and / or fastest cellular connectivity for wireless voice, Short Message Service (SMS), and / or other data traffic transfers. This may be applied to MO and / or MT transfers.

[0193] In contrast, current multi-network, non-steered SIMs that provide cellular connectivity around the world are reliant on SIM authentication selection to an MNO governed by the strongest signal (from a base station) in proximity to the SIM at any moment in time. In such systems, the defining factor in a SIM authentication to an MNO (where multiple MNO networks are made available to the SIM) can only be determined by one component. This is not representative of whether the selected MNO is the best MNO to authenticate with to achieve the best and / or fastest and / or most stable methodof data transfer provided for a SIM. This may be applied to data, voice and / or SMS transfer between mobile devices on the one hand and devices, servers or other specified endpoints on the other. Countries around the world have many MNO cellular networks (roaming in-country, and roaming country-to-country) to which mobile subscribers can connect. However, when a non-steered SIM (which does not have an assigned network priority), is automatically authenticated to the strongest signal from a cell tower published by an MNO, the SIM may be provided with an authentication to an MNO that has network infrastructure issues. This can mean high levels of latency. This can prevent data, voice and / or SMS traffic passing across that network infrastructure in an acceptable time period, or even at all.

[0194] Examples described herein provide more meaningful and representative automatic MNO network selection methods. Examples offer the fastest network always first, as an alternative to the strongest signal always first. Thus, a SIM may be authenticated anywhere in the world by a tangible, automated processes for enabling the identification of the fastest and the most stable method of mobile (wireless and / or cellular), MO and / or MT data, voice, and / or SMS transfers. Examples may be applied to different types of SIM, including voice, SMS and data SIMs, loT SIMs, and data-only SIMs.

[0195] In examples, latency concerns network speed and may be determined by three primary factors, namely network bandwidth, traffic, and signal strength.

[0196] Examples described herein mitigate the risk of a multi- network, non-steered SIM being automatically authenticated to an MNO cellular network that presents the strongest signal from a base station to the proximity of the SIM, but that may provide the slowest network option. Such a network may present the worst connection experience.

[0197] Examples described herein may identify and prioritise connection to the fastest and / or best MNO network available to a multi-networkSIM. This may provide an optimum authenticated connection, and the best in speed and stability for data transfers. Thus, in accordance with examples, signal strength is not the only steer.

[0198] Examples provide methods of selecting an MNO based on latency, which may be performed by a ON node, such as the network aggregator node 208.

[0199] Techniques described herein may not require any modification to existing devices 100. For example, such a device 100 may not require any modification to the SIM 102 and / or may not require bespoke software to be installed on the device 100. However, anexisting device 100 may be modified to implement at least some of the techniques described herein.

[0200] In some examples described above, an RSS rank is determined based on measured RSS. If two or more radio resources have the same measured RSS, one may be allocated a higher rank than the other. Such allocation may be deterministic or non-deterministic. Alternatively, or additionally, where two or more radio resources have the same measured RSS, RSS may be measured again untilthere is a difference in measured RSS values.

[0201] Examples have been described above in which a procedure is successful if a recorded time for the procedure is less than a threshold time and is unsuccessful if the recorded time for the procedure is more than the threshold time. A predetermined result may be used if the recorded time for the procedure is equal to the threshold time. For example, the procedure may be treated as successful in such a situation.

[0202] In some examples describe above, data records, such as the data records 300 and 400 comprise explicit priority or rank values. Prioritisation and / or ranking may be implied in other examples. For instance, frequency bands may be listed in decreasing priority order in a data record similar to the data record 300 but without including explicit priority values. Similarly, frequency bands may be listed in decreasing RSS order in a data record similar to the data record 400 but without including RSS rank values. In a similar manner, a data record that is similar to the data record 500 may imply an order of frequency band or MNO. For example, MNOs may be listed in order in a data record similar to the data record 500 based on the frequency band with which they are associated, without including explicit frequency band identifiers.

[0203] Examples described above relate to two procedures performed by the network aggregator network 206, namely authentication and latency test procedures. One or more alternative or additional procedures may be performed in other examples. Examples of such procedures include, but are not limited to, jitter tests and error rate tests.

[0204] Examples described above relate to one multi-network SIM 102. A network aggregator may provide numerous such SIMs 102 to numerous customers. Techniques described herein may be readily scaled up accordingly.Examples described above relate to multi-network SIMs 102. Elements of such techniques may be applied more generally to single-network and / or multi-network SIMs. For example, a computer-implemented method may be performed in which an authenticated connection between a device (comprising the SIM) and a wireless communications service provider network is established in response to: (a) successfully authenticating the SIM with the wireless communications service provider network in less than an authentication time threshold; and (b) determining that a latency between (i) the device and (ii) the wireless communications service provider network is less than a latency threshold. The method may be performed by a network node. The network node may be a Quality of Service (QoS) node for the wireless communications service provider network.

[0205] Examples described above relate to controlling a network aggregator node. Such examples may be applied correspondingly to any other network node that is communicatively couplable to a device comprising a multi-networkSIM and to a plurality of wireless communications service provider networks.

[0206] Examples described above relate to identifying a wireless communications service provider based on an association between a radio resource via which an access request is received and the wireless communications service provider. However, an association between an access request and a wireless communications service provider may be identified based on the access request in another manner. For example, the access request may comprise a wireless communications service provider identifier, with the wireless communications service provider identifier identifying a particular wireless communications service provider.

[0207] Additionally, where examples relate to identifying a wireless communications service provider, the wireless communications service provider may be identified explicitly (for example based on a wireless communications service provider identifier) and / or implicitly (for example based on a wireless communications service provider network identifier of a wireless communications service provider network with which the wireless communications service provider is associated).

[0208] In examples described above, radio resources are tested one-at-a-time. This can assist in limiting an amount of test packet data used for such testing. In other examples, multiple or all radio resources may be tested before a selection of a particular radioresource is made. For instance, authentication time and / or latency information may be obtained for multiple radio resources. A preferred radio resource may be selected initially, and less-preferred radio resources may not be selected initially. The preferred radio resource may be considered to be a prioritised radio resource, and the preferred radio resources may be considered to be de-prioritised radio resources.

[0209] Radio Resource Selection

[0210] Examples will be described below that relate to radio resource selection.

[0211] By way of an introduction to such examples, the inventors have identified a problem that currently affects, and that will continue to affect, wireless communications service providers, such as MNOs, on a worldwide basis. This problem concerns ‘sunsetting’, for example of 3G for single MNOs. Such sunsetting pushes all traffic that was traversing networks using 3G onto 2G or, alternatively, to 4G or 5G.

[0212] A complete offering in relation to, for example, 5G, 4G LTE, 4G, and 2G depends on a SIM receiving a radio signal from a RAN to authenticate, and gain a connection, to a wireless communications service provider network.

[0213] Currently, a device with single-network SIM can only obtain a signal to make the connection by the device recognising the strongest signal (in terms of RSS) out of the complete set of each of the individual frequency ranges allocated to the wireless communications service provider that issued the SIM. Such information may be published by the wireless communications service provider, for example.

[0214] Takingthe United Kingdom as an example, but not byway of limitation, significant areas of the United Kingdom have a stronger 2G signal, in terms of RSS, than, for example, 4G and 5G. Devices of subscribers in such areas therefore automatically connect using 2G on the basis of 2G having the strongest RSS. However, 2G almost always has a slower data transfer rate than 4G and 5G. Such devices therefore almost always experience lower data transfer rates using 2G than may otherwise be available. As well as this resulting in lesser service and user experience to subscribers that live and / or work in such areas than might be achievable, such subscriber devices may not be able to fulfil desired functionality effectively or even at all. For example, media streaming capabilities may be significantly negatively impacted.In principle, 2G could be removed from subscriber tariffs such that devices could not connect over 2G at all. However, many subscribers still rely on 2G connectivity, for example in rural and remote areas.

[0215] The inventors have identified that the prejudice in the art that the strongest signal should always be used does not necessarily result in an objectively best connection, for example in terms of data transfer rate. The inventors have identified that, surprisingly, and notwithstanding this prejudice, a connection having a lower-than-highest RSS may have a higher data transfer rate than a connection having the highest RSS and may, therefore, be an objectively better connection to use.

[0216] As will be described in more detail below, a latency test may be conducted (or, more generally, a latency determination may be made), in a similar or analogous manner to that described above in relation to multiple different wireless communications service provider networks, but for a single wireless communications service provider and to enable the single wireless communications service provider always to find and use the fastest radio resource (for example, frequency) amongst those allocated to them. Thus, a wireless communications service provider may find the fastest frequency within frequency bands allocated to the wireless communications service provider, without assuming that this necessarily corresponds to the frequency having the strongest RSS.

[0217] Wireless communications service providers, such as MNOs: (i) do not intend to sunset 2G for a considerable amount of time; (ii) are unable to remove 2G from a subscriber tariff to resolve this problem; and (iii) have no other mechanism to distinguish between frequencies to offer signals to a SIM automatically.

[0218] Examples that will now be described herein provide a solution, or at least ameliorate at least some of these problems.

[0219] Referring to Figure 17, there is shown an example of a graph 1700 representing radio resource allocation.

[0220] The x-axis of the example graph 1700 corresponds to bandwidth in megahertz (MHz). In this example, the x-axis shows 20 MHz spacings. The y-axis of the example graph 1700 corresponds to frequency bands, for example in terms of MHz values. The example graph 1700 shows ten frequency bands, FB 1 to FB 10, by way of example only. A different number of frequency bands may be used in other examples. Frequency band frequencies increase with increasing values of y. For example, the first frequency band,FB 1 , may have an associated frequency (for example, a centre frequency) of 700 MHz, the second frequency band, FB 2, may have an associated frequency of 800 MHz, and so on. Different frequencies may be used in other examples. Differentfrequency bands may have different relative spacings in terms of frequencies with which they are associated in other examples.

[0221] In this example, different frequency bands have different bandwidths. For instance, in this specific example, the first frequency band, FB 1, has a bandwidth of approximately 40 MHz, the second frequency band, FB 2, has a bandwidth of approximately 60 MHz, and so on. Bandwidths may be differentfrom those shown byway of example only in Figure 17.

[0222] As depicted in Figure 17, some frequency bands may be partitioned into multiple partitions. Such partitions may be referred to as “frequency sub-bands”, “sub-bands” or the like. For example, the second frequency band, FB 2, has three partitions in this example, the third frequency band, FB 3, has two partitions in this example, and so on. As also depicted in Figure 17, some frequency bands may be non-partitioned. For example, the first and tenth frequency bands, FB 1 and FB 10, are non-partitioned in this example. Where a frequency band is partitioned, the partitions may all have the same bandwidths as each other, or at least some of the partitions may have different bandwidths from each other. The frequency spectrum may be partitioned in a different manner in other examples.

[0223] The term “radio resource” is used herein to include both frequency bands and partitions thereof. For example, the first frequency band, FB 1 , may be considered to be a radio resource, each of the three partitions of the second frequency band, FB 2, may be considered to be a radio resource, and so on.

[0224] Referring to Figure 18, there is shown another example of a graph 1800 representing radio resource allocation.

[0225] The example graph 1800 corresponds to the example graph 1700, but with radio resource allocation amongst wireless communications service providers depicted. Specifically, in this example, a subset of all of the depicted radio resources has been allocated to a particular wireless communications service provider. In this specific example, one radio resource in the second frequency band, FB 2, one radio resource in the third frequency band, FB 3, two radio resources in the fifth frequency band, FB 5, oneradio resource in the seventh frequency band, FB 7, and one radio resource in the ninth frequency band, FB 9, have been allocated to the particular wireless communications service provider. Although not depicted in Figure 18, the remaining radio resources may have been allocated to one or more further wireless communications service providers.

[0226] The allocation depicted in Figure 18 is by way of example only and not by way of limitation. Radio resources may be allocated differently in another manner. Byway of an example, and not byway of limitation, in the United Kingdom, radio resources may be allocated by The Office of Communications (Ofcom).

[0227] Referring to Figure 19, there is shown another example of a graph 1900 representing radio resource allocation.

[0228] The example graph 1900 corresponds to the example graph 1800, but with only a subset of the allocated radio resources highlighted in the example graph 1800 also highlighted in the example graph 1900.

[0229] The example graph 1800 may, for example, correspond to radio resources allocated to an MNO. The example graph 1900 may, for example, correspond to a subset of those radio resources that the MNO makes available to an MVNO to which the MNO provides a service.

[0230] Referring to Figure 20, there is shown an example of a system 2000.

[0231] In this example, the system 2000 comprises a device 100. The device 100 may correspond to example devices 100 described above.

[0232] In this example, the device 100 establishes radio connectivity with a RAN 202 via an air interface 204. Additionally, in this example, the air interface 204 provides a set of radio resources. In this specific example, the radio resources have been allocated as represented by the example graph 1800 shown in Figure 18. In particular, in this specific example, the air interface 204 comprises six allocated radio resources, denoted “RR A” to “RR F”, as shown in Figure 18. However, the air interface 204 can comprise a different number and / or distribution of allocated radio resources in other examples.

[0233] In this example, the system 2000 comprises a wireless communications service provider network 2002. The wireless communications service provider network 2002 may correspond, in general, to any of the wireless communications service provider networks 210, 212, 214 described above. The wireless communications service provider network 2002 is a network that is controlled and operated by a wireless communicationsservice provider. In this example, the six radio resources, RR A to RR F, are those that have been allocated to the wireless communications service provider that is in control of the wireless communications service provider network 2002.

[0234] In this example, the wireless communications service provider network 2002 comprises a wireless communications service provider network node 2004. The wireless communications service provider network 2002 may comprise more than one wireless communications service provider network node 2004 in other examples. The wireless communications service provider network node 2004 may comprise one or more servers. The wireless communications service provider network node 2004 may be fully or partly virtualised. The wireless communications service provider network node 2004 may correspond, in general, to any one or more of the wireless communications service provider network nodes 216, 218, 220, 222, 224, 226 described above.

[0235] Unlike in the example system 200 described above with reference to Figure 2, the example system 2000 does not comprise a network aggregator network 206. Instead, in this example, the device 100 authenticates directly with the wireless communications service provider network 2002.

[0236] Referring to Figures 21 A and 21 B, there is shown an example of a method 2100 of establishing an authenticated connection.

[0237] At item 2102, the device 100 selects a radio resource on which to try to establish an authenticated connection with the wireless communications service provider network 2002. In this example, the device 100 uses the modem 104 to identify the radio resource from amongst the six radio resources, RR A to RR F, with the highest RSS and select the highest RSS radio resource accordingly. The modem 104 may measure signal strength using Received Signal Strength Indicator (RSSI) or decibels per milliwatt (dBm). The signal strength may be reported as a negative number, with a lower number indicating a stronger signal. The modem 104 may use a Public Land Mobile Network (PLMN) list from the SIM 102 to identify a set of radio resources allocated to the wireless communications service provider that issued the SIM 102. The modem 104 may identify which of those radio resources has the strongest signal strength accordingly. Alternatively, the device 100 may use a data record to select a highest RSS radio resource. Such a data record may indicate relative RSSs of the six radio resources, RR A to RR F. In this specific example, the device 100 selects the second radio resource, RRB, on the basis that the second radio resource, RR B, has the highest RSS amongst the six available radio resources, RR A to RR F.

[0238] At item 2104, the device 100 establishes the authenticated connection with the wireless communications service provider network 2002 via the second radio resource, RR B.

[0239] Establishment of the authenticated connection may involve various authentication procedures, including, but not limited to, at least some of those described above. However, in some examples, an authentication time test, such as that described above, is not used. In this specific example, the SIM 102 is a single-network SIM that only enables the device 100 to access the services of the wireless communications service provider network 2002. Authentication time may therefore not factor into wireless communications service provider network selection.

[0240] At item 2106, the wireless communications service provider network 2002 initiates a latency test. In this specific example, the wireless communications service provider network node 2004 initiates the latency test. In this example, the latency test tests the latency of the authenticated connection established between the device 100 and the wireless communications service provider network 2002 via the second radio resource, RR B.

[0241] In this specific example, the latency is recorded as 100 milliseconds.

[0242] In this example, the wireless communications service provider network 2002 compares the recorded latency with a latency threshold. In this specific example, the latency threshold is 50 milliseconds. However, the latency threshold may be different in other examples. In this specific example, the wireless communications service provider network node 2004 performs the comparison.

[0243] In this example, since the recorded latency (100 milliseconds) is longer than the latency threshold (50 milliseconds), the latency test result is “fail”.

[0244] At item 2108, the wireless communications service provider network 2002 causes the authenticated connection established between the device 100 and the wireless communications service provider network 2002 via the second radio resource, RR B, to terminate.

[0245] In this example, the authenticated connection established between the device 100 and the wireless communications service provider network 2002 via the secondradio resource, RR B, has been terminated because, although it provided the strongest RSS, it did not also provide an acceptable data transfer rate.

[0246] At item 2110, the device 100 selects another radio resource on which to try to establish an authenticated connection with the wireless communications service provider network 2002. In this specific example, the device 100 selects the sixth radio resource, RR F. At item 2110, the device 100 is unable to select the second radio resource, RR B, that was selected at item 2102. The device 100 is unable to select the second radio resource, RR B, since the latency test based on the second radio resource, RR B, failed and is therefore unlikely to succeed at this stage.

[0247] The device 100 may select the other radio resource in various ways. For example, the device 100 may use the modem 104 to identify the remaining radio resource with the highest RSS and selectthat radio resource accordingly. Alternatively, the device 100 may identify the remaining frequency band with the highest RSS from a data record.

[0248] At item 2112, the device 100 establishes the authenticated connection with the wireless communications service provider network 2002 via the sixth radio resource, RR F.

[0249] At item 2114, the wireless communications service provider network 2002 initiates a latency test. In this specific example, the wireless communications service provider network node 2004 initiates the latency test. In this example, the latency test tests the latency of the authenticated connection established between the device 100 and the wireless communications service provider network 2002 via the sixth radio resource, RR F.

[0250] In this specific example, the latency is recorded as 65 milliseconds.

[0251] In this example, the wireless communications service provider network 2002 compares the recorded latency with a latency threshold, which, in this specific example, is 50 milliseconds.

[0252] Again, in this example, since the recorded latency (65 milliseconds) is longer than the latency threshold (50 milliseconds), the latency test result is “fail”.

[0253] At item 2116, the wireless communications service provider network 2002 causes the authenticated connection established between the device 100 and the wireless communications service provider network 2002 via the sixth radio resource, RR F, to terminate.At item 2118, the device 100 selects a further radio resource on which to try to establish an authenticated connection with the wireless communications service provider network 2002. In this specific example, the device 100 selects the third radio resource, RR C. At item 2118, the device 100 is unable to select the second or sixth radio resources, RR B and RR F, that were selected at items 2102 and 2110 respectively. The device 100 is unable to select the second or sixth radio resources, RR B and RR F, since the latency tests based on the second and sixth radio resources, RR B and RR F, failed and are therefore unlikely to succeed at this stage.

[0254] The device 100 may select the further radio resource in various ways. For example, the device 100 may use the modem 104 to identify the remaining radio resource with the highest RSS and select that radio resource accordingly. Alternatively, the device 100 may identify the remaining frequency band with the highest RSS from a data record.

[0255] At item 2122, the device 100 establishes the authenticated connection with the wireless communications service provider network 2002 via the third radio resource, RR C.

[0256] At item 2124, the wireless communications service provider network 2002 initiates a latency test. In this specific example, the wireless communications service provider network node 2004 initiates the latency test. In this example, the latency test tests the latency of the authenticated connection established between the device 100 and the wireless communications service provider network 2002 via the third radio resource, RR C.

[0257] In this specific example, the latency is recorded as 40 milliseconds.

[0258] In this example, the wireless communications service provider network 2002 compares the recorded latency with a latency threshold, which, in this specific example, is 50 milliseconds.

[0259] In this example, since the recorded latency (40 milliseconds) is less than the latency threshold (50 milliseconds), the latency test result is “pass”.

[0260] In response, the wireless communications service provider network 2002 maintains the authenticated connection established between the device 100 and the wireless communications service provider network 2002 via the third radio resource, RR C. The wireless communications service provider network 2002 and device 100 may communicate data with an acceptable data transfer rate accordingly.Referring to Figure 22, there is shown another example of a data record 2200. In this example, the data record 2200 corresponds to example state following the example method 2100 described above with reference to Figures 21 A and 21 B.

[0261] In particular, the example data record 2200 indicates that the second radio resource, RR B, has the strongest RSS, but failed the latency test with a latency of 100 milliseconds, that the sixth radio resource, RR F, has the second-strongest RSS, but also failed the latency test with a latency of 65 milliseconds, that the third radio resource, RR C, has the third-strongest RSS and passed the latency test with a latency of 40 milliseconds, and that a latency test has not yet been conducted in respect of the other radio resources.

[0262] Although the signal strength rank is depicted as being comprised in the example data record 2200, this is primarily to facilitate an understanding of the present disclosure. In some examples, RSS information may not be comprised in the data record 2200. For example, where the data record 2200 is maintained in the wireless communications service provider network 2002, the wireless communications service provider network 2002 may not have access to RSS information from the device 100.

[0263] This example demonstrates, therefore, that selecting the radio resource with the strongest RSS does not necessarily result in the objectively best authenticated connection being established. By latency-testing authenticated connections, an objectively best authenticated connection may be established, maintained and used. This goes against a prejudice in the art that radio resources with the strongest RSS should always be used.

[0264] Such an example is applicable to MNOs, MVNOs, and / or other types of wireless communications service provider. In general, data transfer rates for MVNOs are lower than (or, at least, not as high as) those for MNOs. Latency tests for MVNOs are therefore more likely to fail than those for MNOs, particularly where the same latency thresholds are used. In some examples, different latency thresholds may be used for MNOs on the one hand and MVNOs on the other to reduce the likelihood of excessive MVNO latency test failures.

[0265] In some examples, different latency thresholds may be used for different groups of users. For example, a wireless communications service provider may set differentlatency thresholds for different groups of subscribers, to offer different levels of data transfer rate guarantees or targets.

[0266] Various metrics may be recorded and may be made available. In particular, the wireless communications service provider may make at least some of the metrics available in a CMP. For example, the recorded latency test times may be made available to and by the wireless communications service provider in this manner.

[0267] Thus, a computer-implemented method of controlling a wireless communications service provider network node 2004 is provided. The wireless communications service provider network node 2004 is in a wireless communications service provider network 2002. The wireless communications service provider network node 2004 is communicatively couplable to a device 100 comprising a SIM 102 issued by a wireless communications service provider. The wireless communications service provider network 2002 is controllable by the wireless communications service provider.

[0268] An authenticated connection is established between the wireless communications service provider network 2002 and the device 100 via a first radio resource of a plurality of radio resources allocated to the wireless communications service provider.

[0269] An RSS associated with the first radio resource is at least as strong, at the device 100, as an RSS associated with any other radio resource in the plurality of radio resources. The RSS associated with the first radio resource may therefore be the same as, or stronger than, the RSS associated with any other radio resource in the plurality of radio resources.

[0270] A latency test is performed in respect of the authenticated connection. In response to the latency test indicating an acceptable latency of the authenticated connection, the authenticated connection is maintained. However, in response to the latency test indicating an unacceptable latency of the authenticated connection, the authenticated connection ceases to be used. As explained below, one or more other types of latency determination may be used to determine latency, as an alternative to, or in addition to, a latency test.

[0271] In this manner, a latency test is performed (and / or another type of latency determination is made) even where the first radio resource has the (at least joint) strongest RSS. Where, for example, the first radio resource has a strong RSS, but lowdata transfer rate, the latency test enables an objective assessment to be made that the first radio resource is unlikely to provide acceptable performance, and an authenticated connection established via the first radio resource can be terminated. Where, however, the latency test indicates that the authenticated connection established via the first radio resource provides an acceptable data transfer rate, the authenticated connection may be maintained. Thus, a subscriber may always be provided with the fastest radio resource (or, at least, a sufficiently fast radio resource), even if it is not associated with the strongest RSS.

[0272] The latency test (and / or other type of latency determination) indicating an acceptable latency of the authenticated connection may correspond to (measured, historic and / or predicted) latency being less than a latency threshold. The latency threshold may be selected in different ways.

[0273] The latency test (and / or other type of latency determination) indicating an unacceptable latency of the authenticated connection may correspond to (measured, historic and / or predicted) latency not being less than the latency threshold.

[0274] In some examples, different latency thresholds are used to assess acceptable latency and unacceptable latency. For example, latency may be considered acceptable if latency is below an acceptable latency threshold (for example, 50 milliseconds) and latency may be considered unacceptable if latency is above a different, higher unacceptable latency threshold (for example, 55 milliseconds). A predetermined action may be taken if latency is between the acceptable and unacceptable latency thresholds (for example, if the latency is 53 milliseconds). An example of such a predetermined action is a latency retest.

[0275] The latency threshold (associated with the first radio resource) may be the same for all radio resources in the plurality of radio resources (those allocated to the wireless communications service provider). This may enable a target latency to be set, and any radio resource meeting the target latency may be deemed acceptable.

[0276] Alternatively, the latency threshold (associated with the first radio resource) may be different from at least one latency threshold of at least one other radio resource in the plurality of radio resources (those allocated to the wireless communications service provider). For example, a relatively low latency threshold (for example, 50 milliseconds) may be used as the latency threshold associated with the first radio resource and arelatively high latency threshold (for example, 55 milliseconds) may be used as another latency threshold to provide more relaxed latency testing for another radio resource. In particular, a wireless communications service provider may predict that data transfer rates for connections via the other radio resource will increase shortly.

[0277] The latency threshold may be adjusted in response to a latency threshold adjustment trigger. Adjusting the latency threshold may comprise increasing or decreasing the latency threshold. This allows the latency testing to be relaxed and / or tightened.

[0278] Each radio resource in the plurality of radio resources (those allocated to the wireless communications service provider) may correspond to all or part of a respective radio frequency band. This aligns with subdivision of the electromagnetic spectrum, for example as shown in Figures 17 to 19 and described above.

[0279] A further latency test (and / or other type of latency determination) may be conducted in respect of the authenticated connection in response to a latency retest trigger. The latency retest trigger may comprise expiry of a timer and / or may comprise a threshold number of user requests having been received from the device 100 via the authenticated connection. This facilitates an ongoing, objective assessment of suitability of the authenticated connection. If, for example, latency increases beyond an acceptable latency threshold, remedial action may betaken, for example by causing the authenticated connection to terminate. Where the device 100 is a mobile device, radio conditions can change as the device 100 moves. Latency retests enable such changing radio conditions to be accounted for. Latency retests may also account for changing network conditions.

[0280] Ceasing using the authenticated connection may comprise causing the device 100 to cease using the authenticated connection. In response, the device 100 may try to establish a further authenticated connection via a different radio resource. However, the authenticated connection may be terminated in another manner. For example, the wireless communications service provider network node 2004 may terminate the authenticated connection itself.

[0281] A further authenticated connection may be established between the wireless communications service provider network 2002 and the device 100 via a second radio resource of the plurality of radio resources allocated to the wireless communicationsservice provider. An RSS associated with the second radio resource may be less strong, at the device 100, than the RSS associated with the first radio resource. A latency test (and / or other type of latency determination) may be performed in respect of the further authenticated connection. In response to the latency test (and / or other type of latency determination) indicatingan acceptable latency of thefurtherauthenticated connection, the further authenticated connection maybe maintained. In response to the latencytest (and / or other type of latency determination) indicating an unacceptable latency of the further authenticated connection, the further authenticated connection may cease to be used. Thus, even if the first radio resource, having the (at least joint) strongest RSS does not provide an acceptable data transfer rate, a further radio resource may be latency-tested (and / or other type of latency determination may be made in respect of the further radio resource). This process may continue iteratively, in descending RSS order, until a radio resource having an acceptable latency is identified. An authenticated connection may be established and maintained via such a radio resource.

[0282] The wireless communications service provider network 2002 may comprise an MNO network, and the wireless communications service provider may comprise an MNO. The wireless communications service provider network 2002 may comprise an MVNO network, and the wireless communications service provider may comprise an MVNO. Thus, examples are compatible with MNOs, MVNOs and / or other wireless communications service providers.

[0283] The SIM 102 may be a single-network SIM 102. Thus, a single wireless communications service provider may provide its subscribers with acceptable data transfer rates, even where this is not via the radio resource with the strongest RSS.

[0284] A computer-implemented method of controlling a wireless communications service provider network node 2004 may also be provided.

[0285] The wireless communications service provider network node 2004 may be in a wireless communications service provider network 2002 and may be communicatively couplable to a device 100 comprising a SIM 102 issued by a wireless communications service provider. The wireless communications service provider network 2002 may be controllable by the wireless communications service provider.

[0286] An authenticated connection may be established between the wireless communications service provider network 2002 and the device 100 via a first radioresource of a plurality of radio resources allocated to the wireless communications service provider. An RSS associated with the first radio resource may be at least as strong, at the device 100, as an RSS associated with any other radio resource in the plurality of radio resources.

[0287] In response to determining that latency of the authenticated connection is acceptable, the authenticated connection may be maintained. In response to determining that latency of the authenticated connection is unacceptable, the authenticated connection may cease to be used.

[0288] The latency determination may take different forms.

[0289] For example, the latency determination may be based on one or more latency tests, such as described above.

[0290] Alternatively, or additionally, the latency determination may be based on a latency data look-up. For example, historic latency data in respect of the device 100 may be stored and queried as part of the latency determination. A data record such as the data record 2200 may be used to store such historic latency data. Such historic latency data may associate radio resources with respective latency indicators. Examples of latency indicators include, but are not limited to, latency times and latency test results. If a given radio resource which the device 100 has established an authenticated connection is known to have unacceptable latency, the authenticated connection may be deemed not to have acceptable latency and may be terminated based on the latency data look-up, potentially without conducting a further latency test in respect of the authenticated connection. The effectiveness of latency data look-ups may vary. For example, latency data look-ups may be sufficiently effective for a device 100 that is in a fixed location, with relatively static radio conditions, but may not be sufficiently effective for a mobile device 100 with regularly changing radio conditions. A real-time latency test may therefore provide a more accurate indication of real-time data transfer rates, relative to those based on historic latency data.

[0291] Alternatively, or additionally, the latency determination may be based on a latency prediction technique. Such a technique may use machine learning (ML). For example, an ML model may be trained to predict a latency indicator for a connection with a particular device 100 based on historic latency data relating to historic connections with that device 100. The ML model may be used to infer a predicted latency indicatorwhen a determination is being made on whether to maintain or terminate an authenticated connection. For instance, the ML model may predict that a given authenticated connection established via a given radio resource is unlikely to have acceptable latency because the radio resource is associated with high latency times in the training data.

[0292] Multiple types of latency determination may be used together. For example, a latency data look-up may be used to determine whether a given authenticated connection is likely to have an acceptable latency. If the authenticated connection is likely to have an acceptable latency, a latency test may be conducted in respect of the authenticated connection to ensure that the (real-time) latency is acceptable and may be maintained. If, however, the authenticated connection is unlikely to have an acceptable latency, the authenticated connection may be terminated. Such a hybrid approach may help manage an amount of test data communicated, for example in relation to latency test data packets.

[0293] While various forms of latency determination (including, but not limited to, (realtime) latency tests, look-ups, and predictive techniques) have been described in relation to radio resource selection, they are equally applicable to wireless communications service provider network selection as described above. Thus, examples relating to conducting latency tests to select wireless communications service provider networks are applicable, more generally, to any type of latency determination. Nevertheless, (realtime) latency tests are likely to provide a more accurate indication of current data transfer rates than certain other types of latency determination, and so are more likely to offer assurances that target data transfer rates will be achieved.

[0294] A node, such as the wireless communications service provider network node 2004, configured to perform such methods may be provided.

[0295] A computer-implemented method of controlling a device 100 comprising a SIM 102 issued by a wireless communications service provider may be provided.

[0296] Afirst radio resource may be selected from a plurality of radio resources allocated to the wireless communications service provider. An RSS associated with the first radio resource may be at least as strong, at the device 100, as an RSS associated with any other radio resource in the plurality of radio resources.An authenticated connection may be established with a wireless communications service provider network 2002 via the first radio resource. The wireless communications service provider network 2002 may be controllable by the wireless communications service provider.

[0297] The authenticated connection may cease to be used in response to a latency test conducted by a wireless communications service provider network node 2004 in the wireless communications service provider network 2002 indicating that the authenticated connection has an unacceptable latency. Another type of latency determination may be used in addition to, or as an alternative to, a latency test to determine latency.

[0298] A second radio resource from a subset of the plurality of radio resources may be selected. The subset of the plurality of radio resources may exclude the first radio resource. An RSS associated with the second radio resource may be less strong (or, at least, no stronger), at the device 100, than the RSS associated with the first radio resource.

[0299] A further authenticated connection may be established with the wireless communications service provider network 2002 via the second radio resource.

[0300] The further authenticated connection may be maintained in response to a further latency test conducted by the wireless communications service provider network node 2004 indicating that the further authenticated connection has an acceptable latency. Another type of latency determination may be used in addition to, or as an alternative to, a latency test to determine latency.

[0301] The SIM 102 may be a single-network SIM 102.

[0302] A computer-implemented method of controlling a device 100 may also be provided.

[0303] A radio resource may be selected from a set of radio resources. The selected radio resource may have the strongest RSS amongst a plurality of radio resources allocated to a wireless communications service provider.

[0304] An attempt may be made to establish, via the selected radio resource, an authenticated connection havingan acceptable latency with a wireless communications service provider network 2002 of the wireless communications service provider.In response to the attempt to establish the authenticated connection having the acceptable latency being unsuccessful, the selecting and attempting may be repeated with one or more further radio resources of the set of radio resources until an authenticated connection having the acceptable latency has been established. The one or more further radio resources may have lower RSSs than the selected radio resource.

[0305] A device 100 configured to perform such methods may be provided.

[0306] A system, such as the system 2000, comprising a node 2004 and a device 100 may be provided.

[0307] A computer program configured to perform such methods may be provided.The following numbered clauses on pages 50 to 57 of the present description correspond to the claims of UK patent application no.2417392.4, from which the present application claims priority, as filed. The claims of the present application as filed can be found on the subsequent pages 58 to 63 of the specification which begin with the heading “Claims”.

[0308] 1. A computer-implemented method of controlling a network node, the network node being communicatively couplable to a device comprising a multi-network subscriber identity module, SIM, and being communicatively couplable to a plurality of wireless communications service provider networks, a wireless communications service provider network being controllable by a respective wireless communications service provider, the method comprising:

[0309] receiving an access request from the device;

[0310] identifying, based on the access request, a first wireless communications service provider from amongst the plurality of wireless communications service providers; and attempting to authenticate the multi-network SIM with a wireless communications service provider network of the first wireless communications service provider,

[0311] wherein, in response to successful authentication of the multi-network SIM with the wireless communications service provider network of the first wireless communications service provider, the method comprises performing a latency test in respect of a communication channel between the device and the wireless communications service provider network of the first wireless communications service provider, and

[0312] wherein, in response to the latency test indicating an acceptable latency of the data communication channel between the device and the wireless communications service provider network of the first wireless communications service provider, the method comprises establishing an authenticated connection between the device and the wireless communications service provider network of the first wireless communications service provider.2. A method according to clause 1 , wherein the access request is received from the device via a first radio resource, and wherein the first wireless communications service provider is identified based on an association between the first radio resource and the first wireless communications service provider.

[0313] 3. A method according to clause 2, wherein, in response to unsuccessful authentication of the multi-network SIM with the wireless communications service provider network of the first wireless communications service provider, the method comprises:

[0314] causing the device to cease using the first radio resource.

[0315] 4. A method according to clause 2 or 3, wherein, in response to the latency test indicating an unacceptable latency of the communication channel between the device and the wireless communications service provider network of the first wireless communications service provider, the method comprises:

[0316] causing the device to cease using the first radio resource.

[0317] 5. Amethod accordingto clause4, whereinthe latencytestindicatingan acceptable latency of the communication channel between the device and the wireless communications service provider network of the first wireless communications service provider corresponds to latency being less than a latency threshold, and wherein the latency test indicating an unacceptable latency of the communication channel between the device and the wireless communications service provider network of the first wireless communications service provider corresponds to latency not being less than the latency threshold.

[0318] 6. A method accordingto clause 5, wherein the latency threshold is the same for all wireless communications service providers in the plurality of wireless communications service providers.

[0319] 7. A method accordingto clause 5 or 6, comprising:adjusting the latency threshold in response to a latency threshold adjustment trigger.

[0320] 8. A method according to clause 7, wherein adjusting the latency threshold comprises:

[0321] increasingthe latency threshold.

[0322] 9. A method according to any of clauses 2 to 8, wherein the first radio resource comprises a first radio frequency band, and wherein each wireless communications service provider of the plurality of wireless communications service providers has been allocated a respective radio frequency band.

[0323] 10. A method according to any of clauses 1 to 9, wherein successful authentication of the multi-network SIM with the first wireless communications service provider network corresponds to authentication with the first wireless communications service provider network being completed in less than an authentication time threshold, and wherein unsuccessful authentication of the multi-network SIM with the first wireless communications service provider network corresponds to authentication with the first wireless communications service provider network not being completed in less than the authentication time threshold.

[0324] 11. A method according to clause 10, wherein the authentication time threshold is the same for all wireless communications service providers in the plurality of wireless communications service providers.

[0325] 12. A method accordingto clause 10 or 11, comprising:

[0326] adjustingthe authentication time threshold in response to an authentication time threshold adjustment trigger.

[0327] 13. A method according to clause 12, wherein adjusting the authentication time threshold comprises:

[0328] increasingthe authentication time threshold.14. Amethod accordingto any of clauses 1 to 13, wherein the latency test comprises: determining a latency of a first communication channel leg between the network node and the first wireless communications service provider network;

[0329] determining a latency of a second communication channel leg between the network node and the device; and

[0330] using a sum of the latencies of the first and second communication channel legs as the latency of the communication channel between the device and the first wireless communications service provider network.

[0331] 15. A method according to any of clauses 1 to 14, wherein the access request is to a private access point name, APN, of the network node, and wherein the private APN is private to the multi-network SIM.

[0332] 16. A method according to any of clauses 1 to 15, comprising conducting a further latency test in respect of the communication channel between the device and the first wireless communications service provider network in response to a latency retest trigger.

[0333] 17. A method according to clause 16, wherein the latency retest trigger comprises expiry of a timer.

[0334] 18. A method according to clause 17, wherein the latency retest trigger comprises a threshold number of user requests having been received from the device via the authenticated connection.

[0335] 19. A method accordingto any of clauses 1 to 18, comprising:

[0336] receiving a further access request from the device;

[0337] identifying, based on the further access request, a second wireless communications service provider from amongst the plurality of wireless communications service providers; andattempting to authenticate the multi-network SIM with a wireless communications service provider network of the second wireless communications service provider,

[0338] wherein, in response to successful authentication of the multi-network SIM with the second wireless communications service provider network, the method comprises performing a latency test in respect of a communication channel between the device and the second wireless communications service provider network, and

[0339] wherein, in response to the latency test indicating an acceptable latency of the communication channel between the device and the second wireless communications service provider network, the method comprises establishing an authenticated connection between the device and the second wireless communications service provider network.

[0340] 20. A method according to any of clauses 1 to 19, wherein the network node comprises a network aggregator node.

[0341] 21. A computer-implemented method comprising:

[0342] selecting a wireless communications service provider from amongst a plurality of wireless communications service providers associated with a multi-network subscriber identity module, SIM, in response to:

[0343] successfully authenticating the multi-network SIM with the wireless communications service provider in less than an authentication time threshold; and

[0344] determining that a latency between (i) a device comprising the multinetwork SIM and (ii) a wireless communications service provider network of the wireless communications service provider is less than a latency threshold; and establishing an authenticated connection between the device and the wireless communications service provider network.

[0345] 22. A computer-implemented method comprising:

[0346] selecting a wireless communications service provider in preference to any other wireless communications service provider in a plurality of wireless communicationsservice providers associated with a multi- network subscriber identity module, SIM, in response to:

[0347] successfully authenticating the multi-network SIM with the wireless communications service provider; and

[0348] successfully completing a latency test between a wireless communications service provider network of the wireless communications service provider and a device comprising the multi-network SIM,

[0349] wherein the wireless communications service provider is selected even if a latency between a wireless communications service provider network of another wireless communications service provider in the plurality of wireless communications service providers and the device comprising the multi-network SIM is lower than a latency between the wireless communications service provider network of the wireless communications service provider and the device comprising the multi-network SIM.

[0350] 23. A node configured to perform a method according to any of clauses 1 to 22.

[0351] 24. A computer-implemented method of controlling a device comprising a multinetwork subscriber identity module, SIM, the method comprising:

[0352] selecting a first radio resource from a set of radio resources available to the multinetwork SIM;

[0353] transmitting a first access request to a network node via the first radio resource, the network node being communicatively couplable to the device and to a plurality of wireless communications service provider networks;

[0354] ceasing using the first radio resource in response to a trigger event; selecting a second radio resource from a subset of the set of radio resources, the subset of the set of radio resources excluding the first radio resource; and transmitting a second access request to the network node via the second radio resource.

[0355] 25. A computer-implemented method according to clause 24, wherein the multinetwork SIM is a multi-network, steered SIM, wherein the first radio resource is selected as a highest priority radio resource of the set of radio resources, and wherein the secondradio resource is selected as a highest priority radio resource of the subset of the set of radio resources.

[0356] 26. A computer-implemented method according to clause 24, wherein the multinetwork SIM is a multi-network, non-steered SIM, wherein the first radio resource is selected as a highest received signal strength, RSS, radio resource of the set of radio resources, and wherein the second radio resource is selected as a highest RSS radio resource of the subset of the set of radio resources.

[0357] l. A computer-implemented method according to any of clauses 24 to 26, wherein, in response to ceasing to use a final radio resource in the set of radio resources, the method comprises:

[0358] selecting a radio resource from the set of radio resources; and

[0359] transmitting a further access request to the network node via the selected radio resource.

[0360] 28. A computer-implemented method of controlling a device, the method comprising:

[0361] selecting a radio resource from a set of radio resources;

[0362] attempting to establish an authenticated connection meeting one or more target criteria via the selected radio resource; and

[0363] in response to the attempt to establish the authenticated connection via the selected radio resource being unsuccessful:

[0364] repeating the selecting and attempting with one or more further radio resource of the set of radio resources until an authenticated connection meeting the one or more target criteria has been established.

[0365] 29. A device configured to perform a method according to any of clauses 24 to 28.

[0366] 30. A system comprising a node according to clause 23 and a device according to clause 29.31. A computer-implemented method, the method being performed in a wireless communications service provider network and comprising:

[0367] participating in an authentication procedure with a network node; participating in a latency test with the network node; and

[0368] communicating, via an authenticated connection, with a device comprising a multi-network subscriber identity module, SIM, the authenticated connection having been established in response to:

[0369] (i) the authentication procedure having successfully completed in less than a threshold authentication time; and

[0370] (ii) a latency between the wireless communications service provider network and the device having been less than a threshold latency.

[0371] 32. A computer program configured to perform a method according to any of clauses 1 to 22 and / or a method accordingto any of clauses 24 to 28 and / or a method according to clause 31.

Claims

Claims1. A computer-implemented method of controlling a wireless communications service provider network node, the wireless communications service provider network node being in a wireless communications service provider network and being communicatively couplable to a device comprising a subscriber identity module, SIM, issued by a wireless communications service provider, the wireless communications service provider network being controllable by the wireless communications service provider, the method comprising:establishing an authenticated connection between the wireless communications service provider network and the device via a first radio resource of a plurality of radio resources allocated to the wireless communications service provider, a received signal strength associated with the first radio resource being at least as strong, at the device, as a received signal strength associated with any other radio resource in the plurality of radio resources; andperforming a latency test in respect of the authenticated connection, wherein, in response to the latency test indicating an acceptable latency of the authenticated connection, the method comprises maintaining the authenticated connection, andwherein, in response to the latency test indicating an unacceptable latency of the authenticated connection, the method comprises ceasing using the authenticated connection.

2. A method according to claim 1 , wherein the latency test indicating an acceptable latency of the authenticated connection corresponds to latency being less than a latency threshold.

3. A method according to claim 2, wherein the latency test indicating an unacceptable latency of the authenticated connection corresponds to latency not being less than the latency threshold.

4. A method according to claim 2 or 3, wherein the latency threshold is the same for all radio resources in the plurality of radio resources.

5. A method accordingto claim 2 or3, wherein the latency threshold is differentfrom a latency threshold of another radio resource in the plurality of radio resources.

6. A method accordingto any of claims 2 to 5, comprising:adjusting the latency threshold in response to a latency threshold adjustment trigger.

7. A method according to claim 6, wherein adjusting the latency threshold comprises:increasingthe latency threshold.

8. A method according to claim 6, wherein adjusting the latency threshold comprises:decreasing the latency threshold.

9. A method according to any of claims 1 to 8, wherein each radio resource in the plurality of radio resources corresponds to all or part of a respective radio frequency band.

10. A method according to any of claims 1 to 9, comprising conducting a further latency test in respect of the authenticated connection in response to a latency retest trigger.

11. A method according to claim 10, wherein the latency retest trigger comprises expiry of a timer.

12. A method according to claim 10 or 11, wherein the latency retest trigger comprises a threshold number of user requests having been received from the device via the authenticated connection.

13. A method according to any of claims 1 to 12, wherein ceasing using the authenticated connection comprises causing the device to cease using the authenticated connection.

14. A method accordingto any of claims 1 to 13, comprising:establishing a further authenticated connection between the wireless communications service provider network and the device via a second radio resource of the plurality of radio resources allocated to the wireless communications service provider, a received signal strength associated with the second radio resource being less strong, at the device, than the received signal strength associated with the first radio resource; andperforming a latency test in respect of the further authenticated connection, wherein, in response to the latency test indicating an acceptable latency of the further authenticated connection, the method comprises maintaining the further authenticated connection, andwherein, in response to the latency test indicating an unacceptable latency of the further authenticated connection, the method comprises ceasing using the further authenticated connection.

15. A method according to any of claims 1 to 14, wherein the wireless communications service provider network comprises a mobile network operator, MNO, network, and wherein the wireless communications service provider comprises an MNO.

16. A method according to any of claims 1 to 15, wherein the wireless communications service provider network comprises a mobile virtual network operator, MVNO, network, and wherein the wireless communications service provider comprises an MVNO.

17. A method according to any of claims 1 to 16, wherein the SIM is a single-network SIM.

18. A computer-implemented method of controlling a wireless communications service provider network node, the wireless communications service provider network node being in a wireless communications service provider network and being communicatively couplable to a device comprising a subscriber identity module, SIM, issued by a wireless communications service provider, the wireless communications service provider network being controllable by the wireless communications service provider, the method comprising:establishing an authenticated connection between the wireless communications service provider network and the device via a first radio resource of a plurality of radio resources allocated to the wireless communications service provider, a received signal strength associated with the first radio resource being at least as strong, at the device, as a received signal strength associated with any other radio resource in the plurality of radio resources,wherein, in response to determining that latency of the authenticated connection is acceptable, the method comprises maintainingthe authenticated connection, and wherein, in response to determining that latency of the authenticated connection is unacceptable, the method comprises ceasing usingthe authenticated connection.

19. A node configured to perform a method according to any of claims 1 to 18.

20. A computer-implemented method of controlling a device comprising a subscriber identity module, SIM, issued by a wireless communications service provider, the method comprising:selecting a first radio resource from a plurality of radio resources allocated to the wireless communications service provider, a received signal strength associated with the first radio resource being at least as strong, at the device, as a received signal strength associated with any other radio resource in the plurality of radio resources; establishing an authenticated connection with a wireless communications service provider network via the first radio resource, the wireless communications service provider network being controllable by the wireless communications service provider;ceasing using the authenticated connection in response to a latency test conducted by a wireless communications service provider network node in the wireless communications service provider network indicating that the authenticated connection has an unacceptable latency;selecting a second radio resource from a subset of the plurality of radio resources, the subset of the plurality of radio resources excluding the first radio resource, a received signal strength associated with the second radio resource being less strong, at the device, than the received signal strength associated with the first radio resource;establishing a further authenticated connection with the wireless communications service provider network via the second radio resource; and maintainingthe further authenticated connection in response to a further latency test conducted by the wireless communications service provider network node indicatingthatthefurther authenticated connection has an acceptable latency.

21. A computer-implemented method according to claim 20, wherein the SIM is a single-network SIM.

22. A computer-implemented method of controlling a device, the method comprising:selecting a radio resource from a set of radio resources, the selected radio resource having the strongest received signal strength amongst a plurality of radio resources allocated to a wireless communications service provider;attempting to establish, via the selected radio resource, an authenticated connection having an acceptable latency with a wireless communications service provider network of the wireless communications service provider; andin response to the attempt to establish the authenticated connection having the acceptable latency being unsuccessful:repeating the selecting and attempting with one or more further radio resources of the set of radio resources until an authenticated connection having the acceptable latency has been established, the one or more further radioresources having lower received signal strengths than the selected radio resource.

23. A device configured to perform a method according to any of claims 20 to 22.

24. A system comprising a node according to claim 19 and a device according to claim 23.

25. A computer program configured to perform a method according to any of claims 1 to 18and / ora method accordingto any of claims 20 to 22.

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