Rogue onu detection

Abstract

Methods, systems, and apparatus for identifying rogue Optical Network Unit (ONU) are disclosed. An Optical Line Terminal (OLT) detects error conditions on a passive optical network (PON) that includes optical networking units (ONUs) transmitting over the PON. The OLT disables and enables different sets of ONUs to identify a rogue ONU that is causing an error condition. The OLT classifies ONUs as a first set of suspect ONUs based on the error condition on another ONU being resolved when the suspect ONUs were disabled. The OLT classifies ONUs as a second set of suspect ONUs that causes the error condition to be present when the suspect ONUs are enabled. The OLT identifies the rogue ONU based on the rogue ONU being included in both of the first set of suspect ONUs and the second set of suspect ONUs.

Description

ROGUE ONU DETECTIONBACKGROUND

[0001] A Passive Optical Network (PON) can include an Optical Line Terminal (OLT) and Optical Networking Units (ONUs). The OLT can transmit downstream data traffic to the ONUs, and receives upstream data traffic from the ONUs. The downstream data traffic can include information defining timeslots for the individual ONUs to transmit.SUMMARY

[0002] Systems, methods, devices, and non-transitory, computer-readable media are disclosed for identifying a rogue ONU on a PON. One example computer-implemented method includes detecting, by an optical line terminal (OLT), one or more error conditions on a passive optical network (PON) that includes a plurality of optical networking units (ONUs) transmitting over the PON; in response to detecting the one or more error conditions on the PON, disabling and enabling, by the OLT, different sets of ONUs on the PON to identify a rogue ONU on the PON that is causing at least one or more error conditions, including: enabling, by the OLT, all of the plurality of ONUs on the PON; determining, by the OLT, a set of non-error reporting ONUs among the plurality of ONUs, where the OLT does not detect at least one of the one or more error conditions during timeslots when non-error reporting ONUs are instructed by the OLT to transmit; sequentially disabling and then re-enabling, by the OLT, each given ONU in the set of non-error reporting ONUs among the plurality of ONUs one at a time until each given ONU in the set of non-error reporting ONUs have been disabled and then reenabled; classifying, by the OLT, one or more of the given ONUs as a first set of suspect ONUs based on at least one of the one or more error conditions on another ONU being resolved when each of the one or more of the given ONUs were disabled; disabling, by the OLT, all ONUs from the set of non-error reporting ONUs that are not experiencing the one or more error conditions when all of the plurality of ONUs on PON are enabled; sequentially enabling and then disabling, by the OLT, each ONU in the set of non-error reporting ONUs one at a time; classifying, by the OLT, one or more of the ONUs in the set of non-error reporting ONUs as a second set of suspect ONUs that causes at least oneof the one or more error conditions to be present when the one or more of the ONUs in the set of non-error reporting ONUs are enabled; and identifying, by the OLT, the rogue ONU that is causing the at least one of the one or more error conditions based on the rogue ONU being included in both of the first set of suspect ONUs and the second set of suspect ONUs; and enabling all of the plurality of ONUs except for the rogue ONU.

[0003] These and other implementations can each optionally include one or more of the following features. In some aspects, disabling and enabling different sets of ONUs on the PON includes: prior to enabling all of the plurality of ONUs on the PON: disabling, by the OLT, all of the plurality of ONUs on the PON; enabling, by the OLT, each given ONU individually while all other ONUs among the plurality of ONUs on the PON remain disabled; and determining, by the OLT, an individual error state of each given ONU based on whether at least one of the one or more error conditions is detected while the given ONU is the only ONU active among the plurality ONUs on the PON.

[0004] Some aspects include determining an individual error state of each given ONU includes determining that all ONUs in the plurality of ONUs are in an individual non-error state based on the one or more error conditions not being detected when any one of the plurality of ONUs is enabled while all the other ONUs remain disabled; and sequentially disabling each given ONU is conditioned on the determination that all the ONUs in the plurality of ONUs are in an individual non-error state.

[0005] In some aspects, determining an individual error state of each given ONU includes determining a set of faulty ONUs based on at least one of the one or more error conditions being detected when each ONU in the set of faulty ONUs is enabled while all the other ONUs remain disabled, the method further including: disabling the set of faulty ONUs; and monitoring for the one or more error conditions while the set of faulty ONUs are disabled and a set of non-faulty ONUs remain enabled on the PON.

[0006] Some aspects include declaring an alarm for the set of faulty ONUs.

[0007] In some aspects, identifying the rogue ONU that is causing the at least one of the one or more error conditions based on the rogue ONU being included in both of the first set of suspect ONUs and the second set of suspect ONUs includes: determining whether the first set of suspect ONUs and the second set of suspect ONUs consist of a single matching rogue ONU; and in response to determining that the first set of suspectONUs and the second set of suspect ONUs consist of a single matching rogue ONU, identifying the single matching rogue ONU as the rogue ONU.

[0008] Some aspects include, in response to determining that the first set of suspect ONUs and the second set of suspect ONUs do not consist of a any matching rogue ONU, determining that the rogue ONU cannot be determined.

[0009] In some aspects, the one or more error conditions on the PON includes interference during transmissions from one or more of the ONUs in the plurality of ONUs.

[0010] Some aspects include enabling the one or more of the given ONUs based on the at least one of the one or more error conditions on the another ONU not being resolved when the one or more of the given ONUs were disabled.

[0011] In some aspects, disabling and enabling different sets of ONUs on the PON includes:

[0012] skipping the sequentially enabling each ONU in the set of non-error reporting ONUs based on a presence of at least one of the one or more error conditions when all ONUs from the set of non-error reporting ONUs are disabled.

[0013] In some aspects, classifying the one or more of the ONUs in the set of non- error reporting ONUs as the second set of suspect ONUs includes disabling the one or more of the ONUs in the second set of suspect ONUs.

[0014] Some aspects include performing at least one remedial action including at least one of: disabling the rogue ONU; declaring an alarm; and enabling all other ONUs among the plurality of ONUs.

[0015] Particular embodiments of the subject matter described in this specification can be implemented so as to realize one or more of the following advantages. OLT hardware and / or software can detect and / or identify rogue ONUs without manual intervention and without taking the entire network offline for an extended period of time. The rogue ONU can quickly be identified by the OLT in order to minimize system down time. No modification to ONU hardware and / or software is needed, such that the methods, devices and systems described in the present disclosure can work with currently deployed ONUs. In addition, the methods, devices, and systems described in the present disclosure implement an automated rogue ONU detection and identification techniquethat can reliably and rapidly detect and identify a rogue ONU on a Passive Optical Network (PON). The speed and efficiency of identifying rogue ONUs can be increased by implementing the methods, devices, and / or systems described herein to identify rogue ONUs.

[0016] While some aspects of this disclosure generally describe computer- implemented software embodied on tangible media that processes and transforms data, some or all of the aspects may be computer-implemented methods or further included in respective systems or devices for performing the described functionality. The details of one or more embodiments of the subject matter described in this specification are set forth in the accompanying drawings and the description below. Other features, aspects, and advantages of the subject matter will become apparent from the description, the drawings, and the claims.DESCRIPTION OF DRAWINGS

[0017] FIG. l is a block diagram illustrating an example optical networking environment for automatically identifying rogue ONU.

[0018] FIG. 2 is a block diagram of an example OLT.

[0019] FIG. 3 is a flow chart of an example process for verifying that each ONU runs error-free when other ONUs on the PON are disabled.

[0020] FIG. 4 is a flow chart of an example process for identifying rogue ONUs by disabling one ONU at a time.

[0021] FIG. 5 is a flow chart of an example process for identifying rogue ONUs by enabling one ONU at a time.

[0022] FIG. 6 is a flow chart of an example process for identifying rogue ONUs by comparing lists of rogue ONUs.

[0023] FIG. 7 is a flow chart of an example process for identifying rogue ONUs.

[0024] Like reference numbers and designations in the various drawings indicate like elements.DETAILED DESCRIPTION

[0025] The present disclosure describes methods, systems, and apparatus for identifying a rogue Optical Networking Unit (ONU) on a passive optical network (PON). An Optical Line Terminal (OLT) can detect an error on the PON, and determine that none of the ONUs on the PON are causing the error on their own (e.g., there are no problems with any ONU individually). The OLT can disable and enable ONUs on the PON to identify the rogue ONU which is causing the error based on whether the errors on one or more ONUs disappear when another ONU is disabled. For example, the rogue ONU may be causing problems for transmissions of another ONU, and the OLT can detect errors when the other ONU transmits. As such, when the rogue ONU is disabled the errors on the other ONU will no longer be detected by the OLT. In some implementations, the OLT can disable the rogue ONU and / or raise an alarm.

[0026] FIG. l is a block diagram illustrating an example optical networking environment 100 in which rogue ONU(s) can be detected and / or identified. As illustrated in FIG. 1, the environment 100 includes a passive optical network (PON) 102 that connects users to a network 130. In some implementations, the environment 100 may include additional and / or different components not shown in the block diagram, such as one or more active optical networks (AONs), another type of network that provides network services (e.g., ADSL2+, VDSL2, etc.), or a combination of these and other technologies. In some implementations, components may also be omitted from the environment 100.

[0027] The network 130 facilitates wireless or wireline communications between the components of the PON 102 with any other local or remote computer, such as additional PONs, servers, or other devices communicably coupled to the network 130, including those not illustrated in FIG. 1. As illustrated in FIG. 1, the network 130 is depicted as a single network, but may be a combination of more than one network without departing from the scope of this disclosure.

[0028] In some implementations, one or more of the illustrated components may be included within network 130 as one or more cloud-based services or operations. The network 130 may be all or a portion of an enterprise or secured network, while in another case, at least a portion of the network 130 may represent a connection to the Internet, apublic switched telephone network (PSTN), a data server, a video server, or additional or different networks. In some implementations, a portion of the network 130 may be a virtual private network (VPN). Further, all or a portion of the network 130 can comprise either a wireline or wireless link. Example wireless links may include802.1 lac / ad / af / ax / a / b / g / n, 802.20, WiMax, LTE, and / or any other appropriate wireless links. In other words, the network 130 encompasses any internal or external network, networks, sub-network, or combination thereof, operable to facilitate communications between various computing components, inside and outside the environment 100. The network 130 may communicate, for example, Internet Protocol (IP) packets, Frame Relay frames, Asynchronous Transfer Mode (ATM) cells, voice, video, data, and other suitable information between network addresses. The network 130 may also include one or more local area networks (LANs), radio access networks (RANs), metropolitan area networks (MANs), wide area networks (WANs), all or a portion of the Internet, and / or any other communication system or systems at one or more locations.

[0029] The PON 102 includes an OLT 104 (e.g., at a service provider’s central office or other distribution point), a splitter 108, and ONUs 110, 112, and 114. Using the splitter 108, the OLT 104 is coupled to the ONUs 110, 112, and 114 (also referred to as optical network terminals (ONTs)), which are located near end users, thereby forming a point-to- multipoint network. For example, in the case of Gigabit Passive Optical Network (GPON), a single OLT port can connect to 64 (or another number of) different ONUs through the splitter 108. To serve multiple customers on the same network, the GPON uses logical multiplexing in a downstream direction and time-division multiplexing in an upstream direction. The PON 102 includes a link 122 connecting the OLT 104 and the splitter 108, a link 124 connecting the ONU 110 and the splitter 108, a link 126 connecting the ONU 112 and the splitter 108, and a link 128 connecting the ONU 114 and the splitter 108. In some examples, the links 122, 124, 126, and 128 are fiber optic links.

[0030] Each ONU can include, or otherwise be coupled to, one or more customerpremises equipment (CPE) or subscriber devices (e.g., CPE modems). For example, the ONU 110 is a device that terminates the PON 102 at the customer end, and provides a service connection to a user at a residential or commercial location. In some examples,the ONU 1 10 terminates optical fiber transmission, and can transform incoming optical signals into electrical signals, adapted for processing by subscriber devices. As a result, ONUs can provide network services, for example, to residential locations, business locations, or other forms of communications infrastructure, such as wireless communications equipment.

[0031] The OLT 104, as a network distribution element, provides an interface between the PON 102 and the network 130. The OLT 104 transmits downstream data traffic to the ONUs (e.g., ONUs 110, 112, and 114), and receives upstream data traffic from the ONUs. The OLT 104 can detect and / or identify error conditions on the PON 102. In some implementations, the OLT 104 can measure parameters on the link 122. For example, the OLT 104 can measure the optical power received over the link 122 during time slots assigned to each ONU on the PON 102. In some implementations, the OLT 104 can receive parameters (e.g., a reported error, a bad transmission) in the upstream traffic from other component on the PON 102. The OLT 104 can use the parameters to determine the error conditions.

[0032] As discussed in detail with reference to FIGs. 3-7, the OLT 104 can use the parameters on the link 122 to identify the rogue ONU. For example, the OLT can use processes 300, 400, 500, or 600 to identify one or more rogue ONUs. Timely identification of rogue ONUs can improve the performance of the PON because the rogue ONU may not cause any error conditions when enabled individually, but may cause error conditions on other ONUs of the PON (e.g., during time slots assigned to other ONUs), which degrades the performance of the PON. For example, ONU 112 could be a rogue ONU and may transmit (e.g., broadcast a non-zero amount of optical power on a link) erdy during the timeslots assigned to ONU 110 and not during other time slots. In such an example, ONU 112 causes errors during the timeslots assigned to ONU 110, but not during the timeslots assigned to ONU 114. In some examples, ONU 112 can transmit during time slots assigned to multiple other ONUs (e g., ONU 112 transmits all the time) and cause error conditions during time slots assigned to multiple (e.g., all) other ONUs on the PON 102. In this example, the transmission of optical power by the ONU 112 during the timeslots of other ONUs can cause errors during the transmission of optical power by other ONUs, but will not negatively affect the transmissions of the ONU 112.

[0033] FIG. 2 is a block diagram of an example OLT 200. In some implementations, the OLT 200 may include additional and / or different components not shown in the block diagram. Components may also be omitted from the OLT transmitter 200. The components illustrated in FIG. 2 may be similar to or different from those described in FIG. 1.

[0034] As illustrated in FIG. 2, the OLT 200 includes a transceiver 202. The transceiver 202 can be configured to transmit and / or receive data streams from ONUs over a fiber optic link (e.g., the link 122). The transceiver 202 includes a transmitter 204 and a receiver 206. In some implementations, the transmitter 204 can transmit data streams to ONUs using logical multiplexing in a downstream direction. The receiver 206 can receive data streams from ONUs using time-division multiplexing in an upstream direction.

[0035] The OLT 200 includes a rogue monitor 208. The rogue monitor 208 includes one or more processors, and can be configured to identify rogue ONU(s) on a PON. The rogue monitor 208 can measure or have access to communication parameters to detect error conditions and identify the rogue ONU(s) on the PON. For example, the rogue monitor 208 can cooperate with the transceiver 202 to enable and disable ONUs on the PON. The rogue monitor 208 can be co-located with the transceiver 202 or at a different location than the transceiver 202 (e.g., the rogue monitor 208 can be in a centralized location and communicate with multiple transceivers).

[0036] In some implementations, the operations performed by the rogue monitor 208 can be implemented as operations performed by a data processing apparatus, on data stored on one or more computer-readable storage devices or received from other sources. The term “data processing apparatus” encompasses all kinds of apparatus, devices, and machines for processing data, including, by way of example, a programmable processor, a computer, a system on a chip, or multiple ones, or combinations of the foregoing. The rogue monitor 208 can also be implemented as special purpose logic circuitry, for example, an FPGA or an application specific integrated circuit (ASIC).

[0037] FIG. 3 is a flow chart of an example process 300 for verifying that each ONU runs error-free when other ONUs on the PON are disabled. The example process 300 can be performed, for example, by one or more telecommunications devices, such as thosedescribed with reference to FIGS. 1 and 2 (e.g., an OLT that is the same or similar to OLT 104 or OLT 200). The example process 300 can also be implemented as instructions stored on a non-transitory, computer-readable medium that, when executed by one or more telecommunications devices (or other data processing apparatus), cause the one or more telecommunications devices to perform the actions of the example process 300.

[0038] An OLT (e g., an OLT that is the same or similar to OLT 104 or OLT 200) prepares a list (All ONU List) of all the ONUs connected on a PON (302). For example, the OLT can determine all of the ONUs which connect to a wider network through the OLT. In such an example, the wider network can include a network that is that same or similar to network 130.

[0039] The OLT disables every ONU in the All ONU List (303). For example, the OLT can send instructions to the ONUs through a fiber optic link to disable and enable ONUs.

[0040] The OLT enables each ONU in the All ONU List one at a time (304). For example, all of the ONUs on the PON can be enabled individually while all other ONUs remain disabled.

[0041] The OLT determines whether the ONU is showing an error (306). The OLT determines an individual error state of the ONU based on whether an error condition is detected (e.g., by the OLT) while the ONU is the only ONU active among the plurality ONUs on the PON.

[0042] In response to determining that the ONU is not showing an error, the OLT skips adding the ONU to an Errored ONU List. The OLT can determine that all ONUs are in an individual non-error state based on the conditions not being detected when any one of the ONUs is enabled while all the other ONUs remain disabled.

[0043] In response to determining that the ONU is showing an error, the OLT adds the ONU to the Errored ONU List (308). The OLT can add faulty ONUs to the Errored ONU List. For example, faulty ONUs cause an error condition on the PON when enabled individually. In some implementations, the OLT determines a set of faulty ONUs based on error conditions being detected when each ONU in the set of faulty ONUs is enabled while all the other ONUs remain disabled. The OLT can determine (or define) the set of faulty ONUs as the ONUs in the Errored ONU List.

[0044] The OLT disables the individual ONU (310). The individual ONU is disabled so that all other ONUs among the plurality of ONUs on the PON remain disabled while each ONU is enabled individually.

[0045] The OLT determines whether the All ONU List is exhausted (312). For example, the OLT can compare the set of ONUs that have been enabled (Enabled ONU List) to the All ONU List. In such an example, the OLT can add ONUs to the Enabled ONU List after they are enabled at 304. When all ONUs in the All ONU List are in the Enabled ONU List, the OLT can determine that the All ONU List is exhausted. In contrast, when all ONUs in the All ONU List are not in the Enabled ONU List, the OLT can determine that the All ONU List is not exhausted.

[0046] In response to determining that the All ONU List is not exhausted, the OLT enables another ONU in the All ONU List (304). In response to determining that the All ONU List is exhausted, the OLT determines whether the Errored ONU List is empty (314).

[0047] In response to determining that the Errored ONU List is not empty, the OLT declares an alarm and terminates processing (316). The alarm can include the individual ONUs from the Errored ONU List are not running clean (e.g., a set of faulty ONUs). The OLT can terminate the rogue ONU detection process so that the errored ONUs can be addressed (e.g., disabled, replaced). In some implementations, the OLT can disable all ONUs in the Errored ONU List.

[0048] In some implementations, the OLT monitors for the error conditions while the ONUs in the Errored ONU List are disabled and a set of non-faulty ONUs remain enabled on the PON. The ONUs that don’t cause errors can be considered to be non- faulty because they alone don’t cause the error condition on the PON when enabled individually. A set of non-faulty ONUs can include rogue ONUs which cause other ONUs to report errors.

[0049] In response to determining that the Errored ONU List is empty, the OLT continues the rogue ONU detection process (318). For example, the OLT can perform process 400 as a continuation of the rogue ONU detection process. The empty Errored ONU List can indicate that none of the ONUs are causing errors on their own, from which the OLT can determine that a rogue ONU is causing the errors on the PON. Tofacilitate identification of the rogue ONU that is causing error conditions on the PON, the OLT can disable and enable different sets of ONUs on the PON. The different sets of ONUs that are disabled / enabled can include one, or more than one, ONU.

[0050] The example process 300 shown in FIG. 3 can be modified or reconfigured to include additional, fewer, or different actions (not shown in FIG. 3), which can be performed in the order shown or in a different order. In some implementations, one or more of the actions can be repeated or iterated, for example, until a terminating condition is reached. In some implementations, one or more of the individual actions shown in FIG. 3 can be executed as multiple separate actions, or one or more subsets of the actions shown in FIG. 3 can be combined and executed as a single action.

[0051] FIG. 4 is a flow chart of an example process 400 for identifying rogue ONUs by disabling one ONU at a time. The example process 400 can be performed, for example, by one or more telecommunications devices, such as those described with reference to FIGS. 1 and 2 (e.g., an OLT that is the same or similar to OLT 104 or OLT 200). The example process 400 can also be implemented as instructions stored on a non- transitory, computer-readable medium that, when executed by one or more telecommunications devices (or other data processing apparatus), cause the one or more telecommunications devices to perform the actions of the example process 400.

[0052] An OLT (e.g., an OLT that is the same or similar to OLT 104 or OLT 200) enables all ONUs in an All ONU List (402). For example, the All ONU List can include a set of non-faulty ONUs determined while performing process 300.

[0053] The OLT generates a Non-error ONU List of all the non-error reporting ONUs (403). After enabling all ONUs in the All ONU List (402), if the OLT does not detect errors in messages received from a given ONU, the OLT can determine that ONU to be a non-error reporting ONU. In an example, there are no ONUs enabled on the PON that cause errors on their own transmissions (after process 300), and when there is a single rogue ONU on the PON, then the rogue ONU is a non-error reporting ONU.

[0054] In some implementations, the OLT can generate an Error Reporting ONU List. When the OLT detects errors in messages received from an ONU, the OLT can determine the ONU to be an error reporting ONU and add the ONU to the Error Reporting ONU List.

[0055] The OLT disables one ONU from the Non-error ONU List at a time (404). Error reporting ONUs (as detected by the OLT) remain enabled in order to identify the rogue ONU. For example, when a rogue ONU is causing errors during transmissions from another ONU, the OLT will detect the errors while both the rogue ONU and other ONU are enabled. However, when the rogue ONU is disabled, errors that are being caused by the rogue ONU during transmissions from the other ONUs will no longer be detected by the OLT.

[0056] The OLT can sequentially disable each given ONU in a set of non-error reporting ONUs among a plurality of ONUs one at a time until each given ONU in the set of non-error reporting ONUs have been disabled one at a time. In some implementations, sequentially disabling each given ONU in a set of non-error reporting ONUs is conditioned on the determination that all the ONUs in the plurality of ONUs are in an individual non-error state (after process 300). The OLT can enable all ONUs on a PON, then disable one at a time the ONUs in a set of non-error reporting ONUs. For example, the OLT can determine that a first ONU is an error reporting ONU, and skip disabling the first ONU. In such an example, the first ONU will remain enabled so that a second ONU interfering with the first ONU can be identified as a rogue ONU. When the OLT determines that errors are not detected in messages from the first ONU when the second ONU is disabled, the OLT can determine that the second ONU is a rogue ONU.

[0057] The OLT determines whether the error conditions on the PON change (e.g., error conditions are no longer detected during transmissions from at least one of the other ONUs) when a given ONU from the Non-error ONU List is disabled (406). For example, the given ONU may be a rogue ONU that is causing errors on the PON (e.g., detected by the OLT) while another ONU is transmitting on the PON, and that error may go away when the given ONU is disabled (e.g., the OLT does not detect errors during transmissions from the other ONU when the given ONU is disabled).

[0058] In response to determining that the error conditions on the PON change, the OLT adds the given ONU that was disabled just prior to the error condition changing (e.g., becoming no longer detectable) to a First Rogue ONU List (e.g., a suspect rogue ONU List) (408). The OLT can classify one or more of the ONUs as a first set of suspect ONUs based on at least one error condition on another ONU being resolved when each ofthe one or more of the given ONUs from the Non-error ONU List were disabled.Disabling a rogue ONU may remove the PON from a rogue state (e g., resolve all error conditions) if the PON includes only one rogue ONU.

[0059] The OLT re-enables the ONU (410). For example, in response to determining that the error conditions on the PON do not change at 406, the OLT skips adding the given ONU to the First Rogue ONU List. The OLT can enable the given ONUs based on at least one error condition on another ONU not being resolved when the one or more of the given ONUs were disabled (the given ONUs are determined to not be rogue). The OLT can re-enable suspect ONUs in order to maintain the rogue state of the PON while additional ONUs are analyzed (e.g., the OLT can determine if errors go away while the additional ONUs are subsequently disabled).

[0060] The OLT determines whether the Non-error ONU List is exhausted (412). For example, the OLT can inspect the list of ONUs that have been disabled one at a time, and compare that to the set of non-error reporting ONUs. When all of the ONUs in the Non- error ONU List are included in the list of ONUs that have been disabled one at a time, the OLT can determine that the ONU List is exhausted. When all of the ONUs in the set of non-error reporting ONUs are not included in the list of ONUs that have been disabled, the OLT can determine that the ONU List is not exhausted. In response to determining that the Non-error ONU List is not exhausted, the OLT disables another non-error reporting ONU (404). The OLT can iteratively disable each non-error reporting ONU one at a time until all non-error reporting ONUs have been disabled.

[0061] In response to determining that the Non-error ONU List is exhausted, the OLT continues the rogue ONU detection process (414), for example, by performing operations of the process 500. When the rogue ONU detection process continues, the First Rogue ONU List could include one rogue ONU, impacted ONUs, or both.

[0062] The example process 400 shown in FIG. 4 can be modified or reconfigured to include additional, fewer, or different actions (not shown in FIG. 4), which can be performed in the order shown or in a different order. In some implementations, one or more of the actions can be repeated or iterated, for example, until a terminating condition is reached. In some implementations, one or more of the individual actions shown inFIG. 4 can be executed as multiple separate actions, or one or more subsets of the actions shown in FIG. 4 can be combined and executed as a single action.

[0063] FIG. 5 is a flow chart of an example process 500 for identifying rogue ONUs by enabling one ONU at a time. The example process 500 can be performed, for example, by one or more telecommunications devices, such as those described with reference to FIGS. 1 and 2 (e.g., an OLT that is the same or similar to OLT 104 or OLTOLT 200). The example process 500 can also be implemented as instructions stored on a non- transitory, computer-readable medium that, when executed by one or more telecommunications devices (or other data processing apparatus), cause the one or more telecommunications devices to perform the actions of the example process 500. The one or more telecommunications devices can perform process 500 and process 400 in any order (e.g., process 500 can be performed before process 400).

[0064] An OLT (e.g., an OLT that is the same or similar to OLT 104 or OLT 200) enables all ONUs in an All ONU List (502). For example, the All ONU List can include a set of non-faulty ONUs that are on the PON.

[0065] The OLT generates a Non-error ONU List of all the non-error reporting ONUs(503). For example the Non-error ONU List can be the same or similar to the Non-error ONU List of FIG. 4.

[0066] The OLT disables all non-error reporting ONUs in the Non-error ONU List(504). After disabling the non-error reporting ONUs, the ONUs with errors (e.g., from the All ONU List, as detected by the OLT) remain enabled. For example, the OLT may detect errors during transmissions from a particular ONU, while the rest of the ONUs (e.g., included the All ONU List) are enabled and non-error reporting. In such an example, all other ONUs on the PON may be disabled while the particular ONU with errors remains enabled.

[0067] The OLT determines whether the enabled ONUs (e.g., ONUs which had detected errors) are running clean (e.g., no errors detected by the OLT) after disabling all of the non-error reporting ONUs (506). For example, the set of non-error reporting ONUs that were disabled may include a rogue ONU which is causing an error on another ONU while it is enabled. By disabling the non-error reporting ONUs, the enabled ONUs will run clean (e.g., no errors will be reported in the messages received from those ONUs) ifthe errors on the enabled ONUs were being caused by a rogue ONU that is included in the set of non-error reporting ONUs. The OLT can determine whether the enabled ONUs are running clean by evaluating messages received from the enabled ONUs, and determining whether those messages include reported errors (e.g., the errors that were being reported before the non-error reporting ONU’s were disabled.)

[0068] In response to determining that not all ONUs are running clean, the OLT continues the rogue ONU detection process (518), for example, by performing operations of the process 600. In this situation, the OLT can skip sequentially enabling each ONU in the set of non-error reporting ONUs (508). For example, in this situation, it may be that the set of ONUs that were not disabled at operation 504 includes a rogue ONU that is causing an error on one or more other ONUs that were not disabled at operation 504.

[0069] In response to determining that all the enabled ONUs are running clean, the OLT enables one of the disabled ONUs from the Non-error ONU List (e.g., the non-error reporting ONUs that were disabled at operation 504) at a time (508). For example, the OLT can sequentially enable each ONU in the set of disabled non-error reporting ONUs one at a time while the other non-error reporting ONUs remain disabled. Enabling the disabled non-error reporting ONUs one at a time can reveal any rogue ONUs that are interfering with the particular ONU with detected errors. For example, when a rogue ONU causing the errors on the particular ONU is disabled, the errors from the particular ONU may disappear (e g., no longer be detected by the OLT). As such, the enabling of one ONU at a time can lead to a determination of the rogue ONU that is causing the errors on the particular ONU when enabling that ONU causes the errors on an ONU to again be detected.

[0070] The OLT determines whether the error conditions on other ONUs on the PON (e.g., the set of ONUs that were not disabled at operation 504) return while the one ONU from the set of non-error reporting ONUs that were disabled at operation 504 is enabled (510). For example, the ONU that is enabled just prior to detecting the error conditions on the other ONUs can be a rogue ONU that is causing the error conditions on the other ONUs.

[0071] In response to determining that the error conditions on the other ONUs on the PON return, the OLT adds the enabled ONU that caused the errors to return (e.g., bedetected by the OLT again) to a Second Rogue ONU List (e.g., another suspect rogue ONU List) (512). The OLT can classify one or more of the ONUs in the set of non-error reporting ONUs as a second set of suspect ONUs. As used herein, the second set of suspect ONUs includes those ONUs from the set of non-error reporting ONUs that were disabled at operation 504 that cause at least one of the one or more error conditions on the set of ONUs that were not disabled at operation 504 to return when it is re-enabled.

[0072] In response to determining that the error conditions on the other ONUs on the PON do not return when a given non-error reporting ONU is re-enabled, the OLT skips adding the ONU to the Second Rogue ONU List, and the OLT disables that ONU (514). As a result of disabling the ONU, all the non-error reporting ONUs on the PON remain disabled while each of the non-error reporting ONUs is enabled individually. The OLT can disable the one or more of the ONUs in the second set of suspect ONUs.

[0073] The OLT determines whether the Non-error ONU List is exhausted (516). For example, the OLT can compare the set of ONUs that have been enabled to the Non-error ONU List. When all ONUs in the Non-error ONU List are in the set of ONUs that have been enabled, the OLT can determine that the Non-error ONU List is exhausted. In contrast, when all ONUs in the Non-error ONU List are not in the set of ONUs that have been enable, the OLT can determine that the Non-error ONU List is not exhausted.

[0074] In response to determining that the Non-error ONU List is not exhausted, the OLT enables another non-error reporting ONU (508). The OLT can iteratively enable each non-error reporting ONU one at a time until all ONUs from the Non-error ONU List have been enabled individually while the ONUs with detected errors remain enabled.

[0075] In response to determining that the Non-error ONU List is exhausted, the OLT continues the rogue ONU detection process (518), for example by performing operations of the process 600. When the rogue ONU detection process continues, the Second Rogue ONU List can include one or more rogue ONUs.

[0076] The example process 500 shown in FIG. 5 can be modified or reconfigured to include additional, fewer, or different actions (not shown in FIG. 5), which can be performed in the order shown or in a different order. In some implementations, one or more of the actions can be repeated or iterated, for example, until a terminating condition is reached. In some implementations, one or more of the individual actions shown inFIG. 5 can be executed as multiple separate actions, or one or more subsets of the actions shown in FIG. 5 can be combined and executed as a single action.

[0077] FIG. 6 is a flow chart of an example process 600 for identifying rogue ONUs by comparing different lists of rogue ONUs (e.g., different lists of suspect rogue ONUs). The example process 600 can be performed, for example, by one or more telecommunications devices, such as those described with reference to FIGS. 1 and 2 (e.g., an OLT that is the same or similar to OLT 104 or OLT 200). The example process 600 can also be implemented as instructions stored on a non-transitory, computer- readable medium that, when executed by one or more telecommunications devices (or other data processing apparatus), cause the one or more telecommunications devices to perform the actions of the example process 600.

[0078] An OLT (e.g., an OLT that is the same or similar to OLT 104 or OLT 200) determines whether a First Rogue ONU List (e.g., the First Rogue ONU List of FIG. 4) matches a Second Rogue ONU List (e.g., the Second Rogue ONU List of FIG. 5) (610). The OLT can determine that both the First Rogue ONU List and the Second Rogue ONU List contain the same single ONU. In some implementations, the OLT can determine whether the first set of suspect ONUs and the second set of suspect ONUs consist of a single matching rogue ONU.

[0079] In response to determining that the ONU lists match, the OLT determines that the rogue ONU is found (614). In response to determining that the first set of suspect ONUs and the second set of suspect ONUs consist of at least a single matching rogue ONU, the OLT identifies the single matching rogue ONU as the rogue ONU. For example, if the both the First Rogue ONU List and the Second Rogue ONU List include a single, matching ONU, the OLT can identify the one ONU in both the First Rogue ONU List and the Second Rogue ONU List a single rogue ONU. The OLT can identify the rogue ONU that is causing the at least one error condition based on the rogue ONU being included in both of the first set of suspect ONUs and the second set of suspect ONUs. The OLT can perform at least one remedial action including disabling the rogue ONU, declaring an alarm, or enabling all other ONUs among the plurality of ONUs except for the rogue ONU.

[0080] In response to determining that the ONU lists do not match, the OLT determines that the rogue ONU cannot be determined (612). In response to determining that the first set of suspect ONUs and the second set of suspect ONUs do not consist of a single matching rogue ONU, the OLT can determine that the rogue ONU cannot be determined. In an example, the First Rogue ONU List may include a rogue ONU which is showing an error condition (e.g., detected by the OLT). In such an example, the rogue ONU may not be included in the Second Rogue ONU List. In an example, the Second Rogue ONU List may include two or more rogue ONUs.

[0081] The example process 600 shown in FIG. 6 can be modified or reconfigured to include additional, fewer, or different actions (not shown in FIG. 6), which can be performed in the order shown or in a different order. In some implementations, one or more of the actions can be repeated or iterated, for example, until a terminating condition is reached. In some implementations, one or more of the individual actions shown in FIG. 6 can be executed as multiple separate actions, or one or more subsets of the actions shown in FIG. 6 can be combined and executed as a single action.

[0082] FIG. 7 is a flow chart of an example process 700 for identifying rogue ONUs. The example process 700 can be performed, for example, by one or more telecommunications devices, such as those described with reference to FIGS. 1 and 2 (e g., an OLT that is the same or similar to OLT 104 or OLT 200). The example process 700 can also be implemented as instructions stored on a non-transitory, computer- readable medium that, when executed by one or more telecommunications devices (or other data processing apparatus), cause the one or more telecommunications devices to perform the actions of the example process 700.

[0083] An OLT detects one or more error conditions on a PON that includes a plurality of ONUs transmitting over the PON (702).

[0084] In response to detecting the one or more error conditions on the PON, the OLT disabling and enables different sets of ONUs on the PON to identify a rogue ONU on the PON that is causing at least one of the one or more error conditions (704).

[0085] The OLT sequentially disables each given ONU in a set of non-error reporting ONUs among the plurality of ONUs one at a time until each given ONU in the set of nonerror reporting ONUs have been disabled (706).

[0086] The OLT classifies one or more of the given ONUs as a first set of suspect ONUs based on at least one of the one or more error conditions on another ONU being resolved when each of the one or more of the given ONUs were disabled (708).

[0087] The OLT disables all ONUs from the set of non-error reporting ONUs that are not experiencing the one or more error conditions when all of the plurality of ONUs are enabled (710).

[0088] The OLT sequentially enables each ONU in the set of non-error reporting ONUs one at a time (712).

[0089] The OLT classifies one or more of the ONUs in the set of non-error reporting ONUs as a second set of suspect ONUs that causes at least one of the one or more error conditions to be present when the one or more of the ONUs in the set of non-error reporting ONUs are enabled (714).

[0090] The OLT identifies the rogue ONU that is causing the at least one of the one or more error conditions based on the rogue ONU being included in both of the first set of suspect ONUs and the second set of suspect ONUs (716).

[0091] The OLT enables all of the plurality of ONUs except for the rogue ONU (718).

[0092] The example process 700 shown in FIG. 7 can be modified or reconfigured to include additional, fewer, or different actions (not shown in FIG. 7), which can be performed in the order shown or in a different order. In some implementations, one or more of the actions can be repeated or iterated, for example, until a terminating condition is reached. In some implementations, one or more of the individual actions shown in FIG. 7 can be executed as multiple separate actions, or one or more subsets of the actions shown in FIG. 7 can be combined and executed as a single action.

[0093] While this specification contains many specific implementation details, these should not be construed as limitations on the scope of any inventions or of what may be claimed, but rather as descriptions of features specific to particular embodiments of particular inventions. Certain features that are described in this specification, in the context of separate embodiments, can also be implemented in combination or in a single embodiment. Conversely, various features that are described in the context of a single embodiment can also be implemented in multiple embodiments, separately, or in anysuitable subcombination. Moreover, although features may be described above as acting in certain combinations and even initially claimed as such, one or more features from a claimed combination can in some cases be excised from the combination, and the claimed combination may be directed to a subcombination, or variation of a subcombination.

[0094] Thus, particular embodiments of the subject matter have been described. Other embodiments are within the scope of the following claims. In some cases, the actions recited in the claims can be performed in a different order and still achieve desirable results. In addition, the processes depicted in the accompanying figures do not necessarily require the particular order shown, or sequential order, to achieve desirable results.

Claims

WHAT IS CLAIMED IS:

1. A method, comprising: detecting, by an optical line terminal (OLT), one or more error conditions on a passive optical network (PON) that includes a plurality of optical networking units (ONUs) transmitting over the PON; in response to detecting the one or more error conditions on the PON, disabling and enabling, by the OLT, different sets of ONUs on the PON to identify a rogue ONU on the PON that is causing at least one or more error conditions, including: enabling, by the OLT, all of the plurality of ONUs on the PON; determining, by the OLT, a set of non-error reporting ONUs among the plurality of ONUs, where the OLT does not detect at least one of the one or more error conditions during timeslots when non-error reporting ONUs are instructed by the OLT to transmit; sequentially disabling and then re-enabling, by the OLT, each given ONU in the set of non-error reporting ONUs among the plurality of ONUs one at a time until each given ONU in the set of non-error reporting ONUs have been disabled and then reenabled; classifying, by the OLT, one or more of the given ONUs as a first set of suspect ONUs based on at least one of the one or more error conditions on another ONU being resolved when each of the one or more of the given ONUs were disabled; disabling, by the OLT, all ONUs from the set of non-error reporting ONUs that are not experiencing the one or more error conditions when all of the plurality of ONUs on PON are enabled; sequentially enabling and then disabling, by the OLT, each ONU in the set of non-error reporting ONUs one at a time; classifying, by the OLT, one or more of the ONUs in the set of non-error reporting ONUs as a second set of suspect ONUs that causes at least one of the one or more error conditions to be present when the one or more of the ONUs in the set of non-error reporting ONUs are enabled; andidentifying, by the OLT, the rogue ONU that is causing the at least one of the one or more error conditions based on the rogue ONU being included in both of the first set of suspect ONUs and the second set of suspect ONUs; and enabling all of the plurality of ONUs except for the rogue ONU.

2. The method of claim 1, wherein disabling and enabling different sets of ONUs on the PON further comprises: prior to enabling all of the plurality of ONUs on the PON: disabling, by the OLT, all of the plurality of ONUs on the PON; enabling, by the OLT, each given ONU individually while all other ONUs among the plurality of ONUs on the PON remain disabled; and determining, by the OLT, an individual error state of each given ONU based on whether at least one of the one or more error conditions is detected while the given ONU is the only ONU active among the plurality ONUs on the PON.

3. The method of claim 2, wherein: determining an individual error state of each given ONU comprises determining that all ONUs in the plurality of ONUs are in an individual non-error state based on the one or more error conditions not being detected when any one of the plurality of ONUs is enabled while all the other ONUs remain disabled; and sequentially disabling each given ONU is conditioned on the determination that all the ONUs in the plurality of ONUs are in an individual non-error state.

4. The method of claim 2, wherein determining an individual error state of each given ONU comprises determining a set of faulty ONUs based on at least one of the one or more error conditions being detected when each ONU in the set of faulty ONUs is enabled while all the other ONUs remain disabled, the method further comprising: disabling the set of faulty ONUs; and monitoring for the one or more error conditions while the set of faulty ONUs are disabled and a set of non-faulty ONUs remain enabled on the PON.

5. The method of claim 4, the method further comprising: declaring an alarm for the set of faulty ONUs.

6. The method of claim 1, wherein identifying the rogue ONU that is causing the at least one of the one or more error conditions based on the rogue ONU being included in both of the first set of suspect ONUs and the second set of suspect ONUs comprises: determining whether the first set of suspect ONUs and the second set of suspect ONUs consist of a single matching rogue ONU; and in response to determining that the first set of suspect ONUs and the second set of suspect ONUs consist of a single matching rogue ONU, identifying the single matching rogue ONU as the rogue ONU.

7. The method of claim 6, further comprising: in response to determining that the first set of suspect ONUs and the second set of suspect ONUs do not consist of a any matching rogue ONU, determining that the rogue ONU cannot be determined.

8. The method of claim 1, wherein the one or more error conditions on the PON comprises interference during transmissions from one or more of the ONUs in the plurality of ONUs.

9. The method of claim 1, further comprising: enabling the one or more of the given ONUs based on the at least one of the one or more error conditions on the another ONU not being resolved when the one or more of the given ONUs were disabled.

10. The method of claim 1, wherein disabling and enabling different sets of ONUs on the PON further comprises: skipping the sequentially enabling each ONU in the set of non-error reporting ONUs based on a presence of at least one of the one or more error conditions when all ONUs from the set of non-error reporting ONUs are disabled.

11. The method of claim 1, wherein classifying the one or more of the ONUs in the set of non-error reporting ONUs as the second set of suspect ONUs comprises disabling the one or more of the ONUs in the second set of suspect ONUs.

12. The method of claim 1, further comprising: performing at least one remedial action comprising at least one of: disabling the rogue ONU; declaring an alarm; and enabling all other ONUs among the plurality of ONUs.

13. A system, comprising: a plurality of optical network units (ONUs) connected to a fiber optic link; and an optical line terminal (OLT) connected to the fiber optic link, wherein the OLT comprises one or more processors configured to perform operations comprising: detecting, by an optical line terminal (OLT), one or more error conditions on a passive optical network (PON) that includes a plurality of optical networking units (ONUs) transmitting over the PON; in response to detecting the one or more error conditions on the PON, disabling and enabling, by the OLT, different sets of ONUs on the PON to identify a rogue ONU on the PON that is causing at least one of the one or more error conditions, including: sequentially disabling, by the OLT, each given ONU in a set of nonerror reporting ONUs among the plurality of ONUs one at a time until each given ONU in the set of non-error reporting ONUs have been disabled; classifying, by the OLT, one or more of the given ONUs as a first set of suspect ONUs based on at least one of the one or more error conditions on another ONU being resolved when each of the one or more of the given ONUs were disabled; disabling, by the OLT, all ONUs from the set of non-error reporting ONUs that are not experiencing the one or more error conditions when all of the plurality of ONUs are enabled;sequentially enabling, by the OLT, each ONU in the set of non-error reporting ONUs one at a time; classifying, by the OLT, one or more of the ONUs in the set of nonerror reporting ONUs as a second set of suspect ONUs that causes at least one of the one or more error conditions to be present when the one or more of the ONUs in the set of nonerror reporting ONUs are enabled; and identifying, by the OLT, the rogue ONU that is causing the at least one of the one or more error conditions based on the rogue ONU being included in both of the first set of suspect ONUs and the second set of suspect ONUs; and enabling all of the plurality of ONUs except for the rogue ONU.

14. The system of claim 13, wherein disabling and enabling different sets of ONUs on the PON further comprises: prior to sequentially disabling each given ONU: disabling, by the OLT, all of the plurality of ONUs on the PON; enabling, by the OLT, each given ONU individually while all other ONUs among the plurality of ONUs on the PON remain disabled; and determining, by the OLT, an individual error state of each given ONU based on whether at least one of the one or more error conditions is detected while the given ONU is the only ONU active among the plurality ONUs on the PON.

15. The system of claim 13, wherein identifying the rogue ONU that is causing the at least one of the one or more error conditions based on the rogue ONU being included in both of the first set of suspect ONUs and the second set of suspect ONUs comprises: determining whether the first set of suspect ONUs and the second set of suspect ONUs consist of a single matching rogue ONU; and in response to determining that the first set of suspect ONUs and the second set of suspect ONUs consist of a single matching rogue ONU, identifying the single matching rogue ONU as the rogue ONU.

16. The system of claim 15, the operations further comprising:in response to determining that the first set of suspect ONUs and the second set of suspect ONUs do not consist of a single matching rogue ONU, determining that the rogue ONU cannot be determined.

17. The system of claim 13, wherein the one or more error conditions on the PON comprises interference during transmissions from one or more of the ONUs in the plurality of ONUs.

18. The system of claim 13, the operations further comprising: enabling the one or more of the given ONUs based on the at least one of the one or more error conditions on the another ONU not being resolved when the one or more of the given ONUs were disabled.

19. The system of claim 13, wherein disabling and enabling different sets of ONUs on the PON further comprises: skipping the sequentially enabling each ONU in the set of non-error reporting ONUs based on a presence of at least one of the one or more error conditions when all ONUs from the set of non-error reporting ONUs are disabled.

20. A non-transitory computer storage medium encoded with instructions that, when executed by one or more processors, cause the one or more processors to perform operations comprising: detecting, by an optical line terminal (OLT), one or more error conditions on a passive optical network (PON) that includes a plurality of optical networking units (ONUs) transmitting over the PON; in response to detecting the one or more error conditions on the PON, disabling and enabling, by the OLT, different sets of ONUs on the PON to identify a rogue ONU on the PON that is causing at least one of the one or more error conditions, including: sequentially disabling, by the OLT, each given ONU in a set of non-error reporting ONUs among the plurality of ONUs one at a time until each given ONU in the set of non-error reporting ONUs have been disabled;classifying, by the OLT, one or more of the given ONUs as a first set of suspect ONUs based on at least one of the one or more error conditions on another ONU being resolved when each of the one or more of the given ONUs were disabled; disabling, by the OLT, all ONUs from the set of non-error reporting ONUs that are not experiencing the one or more error conditions when all of the plurality of ONUs are enabled; sequentially enabling, by the OLT, each ONU in the set of non-error reporting ONUs one at a time; classifying, by the OLT, one or more of the ONUs in the set of non-error reporting ONUs as a second set of suspect ONUs that causes at least one of the one or more error conditions to be present when the one or more of the ONUs in the set of non-error reporting ONUs are enabled; and identifying, by the OLT, the rogue ONU that is causing the at least one of the one or more error conditions based on the rogue ONU being included in both of the first set of suspect ONUs and the second set of suspect ONUs; and enabling all of the plurality of ONUs except for the rogue ONU.

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