Transmitting and receiving aids and transmitting and receiving methods for transmitting a data stream over bundled network access lines

Description

TECHNICAL FIELD

[0001] The invention relates to an arrangement and a method for transmitting a data stream via bundled network access lines as well as to a transmitting and receiving auxiliary device and a transmitting and receiving method therefor. TECHNICAL BACKGROUND

[0002] To transmit a data stream from a transmitting device to a receiving device over a network with a packet-based transmission protocol, in particular over the TCP / IP-based Internet, network access lines in the form of ISDN lines, WLAN radio connections, telephone lines, or the like are typically used to connect the transmitting device and the receiving device. The transmitting device divides the data stream into numbered, consecutive data packets and sends them one after the other to the network over the network access line. In the network, the data packets are transmitted toward the receiving device, where they are extracted from the network via the network access line on the receiving device side and fed to the receiving device. There, the data packets are reassembled to obtain the transmitted data stream.

[0003] The data protocols that have become established in practice for this type of data stream transmission, particularly the Transport Connection Protocol (TCP) based on the Internet Protocol (IP), fundamentally take into account the possibility of data packets being lost in the network. Therefore, it is the responsibility of the receiving device to re-request any data packets that have not arrived from the sending device and to acknowledge receipt of the data packets to the sending device. A loss of data packets is assumed when consecutive data packets arriving at the receiving device are not numbered consecutively. For example, if a data packet with the number 5 arrives after a data packet with the number 2, it is assumed that data packets 3 and 4 have been lost in the network. These data packets are therefore re-requested from the sending device by the receiving device after receiving data packet 5.This ensures that the entire data stream is transmitted.

[0004] However, this peculiarity of the transmission protocols used leads to problems when a transmitting device (or a receiving device) is to be connected to the network via multiple network access lines simultaneously in order to increase usable bandwidth and availability. In this case, the access lines are "bundled," meaning they are combined into a single virtual line from the transmitting device's perspective.

[0005] The data packets are then distributed across multiple network access lines to ensure simultaneous use of the network access lines. If the bundled network access lines are identical in terms of bandwidth and propagation time per data packet and also operate with a synchronous clock, as is the case with ISDN channel bundling, for example, the order in which the data packets arrive at the receiving device can be controlled almost as accurately as when using a single network access line.

[0006] However, if the bundled network access lines differ in terms of bandwidth and / or propagation time and / or if no synchronous clock is used, it cannot be guaranteed that the data packets arrive at the receiving device in the correct order.

[0007] For example, if a network access line with a propagation time of 100 ms per data packet is bundled with another network access line with a propagation time of 250 ms per data packet, the data packets transmitted via the first data line will always arrive at the receiving device faster than those transmitted via the second network access line. If, for example, the data stream is distributed at the transmitting device between the two network access lines in such a way that the first data packet is sent via the first network access line, the second data packet is sent via the second network access line, the third packet is sent via the first network access line, the fourth packet is sent via the second network access line, and so on, the data packets arrive at the receiving device as follows due to the propagation time differences: After 100ms: The first data packet arrives via network access line 1. After 200ms: The third data packet arrives via network access line 1. After 250ms: The second data packet arrives via network access line 2. After 300ms: The fifth data packet arrives via network access line 1. After 400ms: The seventh data packet arrives via network access line 1. etc.

[0008] Due to the different propagation times on the two network access lines, data packets on the first network access line overtake packets on the second network access line. Consequently, the data packets arrive at the receiving device in the wrong order. This incorrect order leads to a significant number of re-requested data packets. Furthermore, the transmitting device reacts to such re-requests or the lack of acknowledgements by throttling the data transmission rate.

[0009] In practice, the propagation times of the network access lines will also vary, making the order of data packet reception unpredictable. This is the case even if the theoretical propagation times of the data packets on the network access lines should be almost identical, but the bandwidths of the bundled network access lines do not match. This is because the available bandwidth, due to intermediate buffers, influences the actual propagation time of a data packet depending on the load. In practice, today's broadband internet access lines, such as DSL, are implemented as a so-called "shared medium," in which several subscribers of a local network share the available bandwidth in the distribution network.This results in constantly fluctuating line properties in terms of bandwidth and thus propagation time, which means that distributing data packets across multiple network access lines inevitably leads to incorrectly sorted data packets at the receiving device.

[0010] Therefore, connecting a second network access line with the same bandwidth does not, in practice, result in the theoretical doubling of usable bandwidth. Instead, there is no increase in usable bandwidth at all, or only a very slight one. Often, disruptions and significant delays in data transfer occur due to the large number of new data packet requests and the throttling of the data transmission rate.

[0011] The obvious approach of reordering the data packets at the receiving device based on their respective sequence numbers is impractical. Since the IP protocol does not guarantee delivery, meaning data packets can be lost, such an approach would conflict with the detection of lost data packets. If, after the first data packet, the third data packet arrives at the receiver instead of the second, it is impossible for the receiving device to determine whether this happened because the third data packet overtook the second, i.e., "packet reordering" occurred during transport, or whether the second data packet was lost en route and therefore will not arrive without a corresponding re-request.

[0012] Therefore, there are only two practical approaches in the state of the art for bundling multiple network access lines.

[0013] In the first approach, only network access lines with exactly the same characteristics in terms of bandwidth and latency are bundled. The bundled network access lines operate with a synchronous clock. This is the case, for example, with ISDN channel bundling. This ensures that the data packets actually arrive at the receiving device in the correct order.

[0014] In the second approach, different network access lines are bundled, but only one of the bundled network access lines is used per data stream to be transmitted. Therefore, the n available lines can only be fully utilized if at least n independent data streams exist simultaneously and the number of data streams is evenly divisible by the number of network access lines.

[0015] US 2002 / 010866 A1 discloses an arrangement for transmitting a data stream from a transmitting device to a receiving device via the Internet. The transmitting device is connected to the network via network access lines, and several network access lines are provided for bundling on the transmitting and / or receiving device side. An initiator interposed between the transmitting device and the network access line(s) is configured to encapsulate data packets of the data stream sent by the transmitting device and transmit the encapsulated data packets to the network via the network access line(s). A responder interposed between the network access line(s) and the receiving device is configured to receive and decapsulate the encapsulated data packets and forward the decapsulated data packets to the receiving device.

[0016] From FR 2 884 997 A1 an arrangement for bundling network access lines is known in which various IP tunnels are bundled between a local end-user device and a remote device.

[0017] RFC 1990 concerns the PPP Multi-link protocol for coordinating multiple links, including asynchronous and synchronous links. TASK

[0018] Proceeding from this, the invention is based on the object of providing an arrangement and a method for transmitting a data stream via bundled network access lines as well as an auxiliary transmitting and receiving device and a transmitting and receiving method therefor, which enable a bundling of network access lines with a corresponding increase in the usable bandwidth.

[0019] This object is achieved according to the features of claims 1, 3, 8, 12, 18 and 21, respectively. BRIEF DESCRIPTION OF THE INVENTION

[0020] This creates devices and methods that enable asynchronous bundling of network access lines for use with the Internet Protocol.

[0021] The invention makes it possible to bundle any number of highly diverse network access lines. By combining different physical line types, the risk of failure of the overall connection is reduced, since, unlike with synchronous bundling, a failure usually affects only one line type. If one of the bundled network access lines fails, e.g., because the provider resets or disconnects the DSL connection every 24 hours, all TCP / IP connections remain intact as long as at least one other of the bundled network access lines is still functional. According to the invention, software such as Skype does not need to establish a new connection and renegotiate parameters, effectively maintaining a leased line.

[0022] Through the bundling according to the invention, the total bandwidth of internet connections can be increased in any desired increments. The overall availability increases almost exponentially with the number of network access lines. Thus, the combination of two independent network access lines with an availability of 98% each results in a total availability of 99.96%.

[0023] According to the invention, network access lines are bundled within any physical sections of a TCP / IP end-to-end connection without adaptation or knowledge of the involved communication endpoints. The section can extend between two computers, each connected to the network via DSL or the like, or between a computer connected to the network via such a connection and an internet node, e.g., the internet backbone, or between two sections of the internet, e.g., two distribution nodes, or between two networks, etc.

[0024] The TCP / IP protocol is end-to-end based, meaning the endpoints of a connection must independently inform each other about the receipt or absence of a data packet. The methods and devices according to the invention therefore operate "invisibly" to the endpoints. Thus, the sending endpoint continues to receive acknowledgements from the auxiliary sending device on behalf of the receiving endpoint, which, in turn, expects the arrival of data packets of a data stream in the correct order.

[0025] According to the invention, the TCP layer is completely decoupled from the transport behavior of the bundled network access lines. Mutual interference is thus eliminated. This is achieved by simulating a virtual reality for the endpoints. For this purpose, a "man in the middle" in the form of an auxiliary transmitting device and an auxiliary receiving device, which can be physically configured as a plug-in card or router or the like, or also as a software layer, acts on both sides under the identity of the other side. In this way, the TCP endpoints are provided with a simulated image of the transport behavior on the network access lines. They preferably receive the information, inserted into the data stream, that all sent data packets of an existing connection have been immediately confirmed by the receiving endpoint and can therefore be forwarded at full speed.

[0026] At the receiving endpoint, all data packets arriving from the bundled network access lines are buffered and correctly sorted according to the invention. This delay is irrelevant for the sending endpoint, as it has already received advance confirmation of receipt of all data packets, allowing the immediate transmission of further data packets. Any potentially conflicting genuine confirmation packets from the receiving endpoint can be filtered out according to the invention.

[0027] Since the TCP endpoints do not receive any information about the state of the transport situation because they are completely decoupled from the actual transport through the network by the sending auxiliary device and the receiving auxiliary device, the responsibility for managing the data transmission lies with the auxiliary devices.

[0028] For this purpose, a dedicated transport protocol is used between the auxiliary devices, which is designed for distributing and sorting data packets. The fact that this protocol is completely decoupled from the TCP / IP layer creates freedom of choice: Transport between the auxiliary devices can be carried out using any suitable protocol. An encrypted VPN connection based on the SSL / TLS method is recommended. This creates a so-called "tunnel." Data packets arriving from outside and intended for transport via the bundled network access lines are encapsulated in an encrypted container packet in which they are transmitted.

[0029] In this case, the incoming data stream is preferably distributed among a number of data streams that corresponds to the number of network access lines on the auxiliary transmission device that are active at the given time, i.e., that are expediently capable of transmitting at a sufficient transmission rate. How the data packets of the incoming data stream are distributed among the outgoing data streams can be expediently continuously redetermined depending on the utilization of the corresponding network access lines.

[0030] Further embodiments, features and advantages of the invention will become apparent from the accompanying drawings, the claims and the following description. FIGURE DESCRIPTION

[0031] Fig. 1 illustrates an embodiment of the arrangement according to the invention. Fig. 2 illustrates data streams with data packets. Fig. 3 illustrates an embodiment of the method according to the invention. Fig. 4illustrates an embodiment of the auxiliary transmission device according to the invention. DESCRIPTION OF THE PREFERRED EMBODIMENTS A. Arrangement according to the invention

[0032] The Figure 1 The arrangement shown for transmitting a data stream a from a transmitting device 1, e.g. a computer in a branch of a company, to a receiving device 2, e.g. a computer in the company's headquarters, via a packet-based network 3, in particular the Internet, which is connected in a wired and wireless manner via physical network access lines 4, 4' coupled in pairs with end-to-end connections, such as DSL lines, WLAN connections, telephone lines, UMTS connections and the like, comprises an auxiliary transmitting device 5 and an auxiliary receiving device 6.

[0033] The transmitting device 1 delivers a data stream a in the form of data packets ai , i=1, 2, 3 ... according to a standardized protocol, in particular according to the TCP / IP protocol, cf. Fig. 2 . The data stream a is addressed to the receiving device 2. Therefore, the transmitting device 1 and the receiving device 2 are connected by an end-to-end connection according to the TCP / IP standard, which is formed between the IP address of the transmitting device 1 and the IP address of the receiving device 2.

[0034] The data stream a is transmitted via a wired or wireless connection 7 to the auxiliary transmission device 5. There, the data packets ai are divided, if necessary encrypted as f(ai ) with a function f and encapsulated into data packets Ai, Bi, Ci, i=1,2,3,...

[0035] The data packets A i , B i , C i are then fed to the network 3 via the network access lines 4, in a manner invisible to the transmitting device 1 as data streams A, B, C. In the network 3, which may be the Internet or any other network using any protocol, the data packets A i , B i , C i are transmitted according to the respective protocol, here for example the TCP / IP protocol, in the direction of the receiving device 6, expediently to a specific network access line 4'. For this purpose, each network access line 4, 4' is assigned a unique IP address, and in the illustrated embodiment, the six network access lines 4, 4' are coupled in pairs to form three end-to-end connections, so that three independent transmission channels are formed between the auxiliary transmitting device 5 and the auxiliary receiving device 6, one for each of the three data streams A, B, C.

[0036] The data packets A i , B i , C i leave the network 3 via the network access lines 4' assigned to the respective data stream and reach the auxiliary receiving device 6. There, they are temporarily stored. The data packets f(ai ) are then decapsulated, decrypted, and sorted. Finally, they are fed in the correct order to the receiving device 2 via a line 7' according to the TCP / IP protocol.

[0037] The transmitting device 1 and the receiving device 2 are completely decoupled from the management of the network access lines 4, 4' and the processing and management of the data packets A i , B i , C i . From the perspective of the transmitting device 1, only the line 7 exists, while from the perspective of the receiving device 2, only the line 7' exists, and both the transmitting device 1 and the receiving device 2 see only the end-to-end connection connecting them, but not the end-to-end connections between the network access lines 4, 4'.

[0038] In other embodiments, the auxiliary receiving device 6 is not located in the network of the receiving device 2. It can be located, for example, at a service provider's location. The line 7' then represents a service provider-side and sufficiently fast connection to the Internet or to another network in which the receiving device is located. The same applies to the auxiliary transmitting device 2; here, too, the transmitting device 1 can be located in a different network. The section between the auxiliary transmitting device 5 and the auxiliary receiving device 6 can thus be any section of an end-to-end connection between a transmitting device 1 and a receiving device 2.

[0039] In a particularly preferred embodiment, the auxiliary receiving device 6 is essentially part of the internet backbone, i.e., it can be connected directly to an internet node, for example, at a network provider. In this case, only one network access line 4' is required, which is expediently designed as a leased line or permanent connection, for example in the form of a cable dimensioned for sufficient data throughput. The auxiliary receiving device 6 can, but does not have to, be assigned an IP address as such; rather, in this case, in principle, all data from one or more or all customers of the network provider can first be automatically routed to the auxiliary receiving device 6, which processes it further and then distributes it accordingly in the network 3.

[0040] If necessary, auxiliary reception devices 6 are already provided in the distribution points of the network 3. In these embodiments, the design of the auxiliary reception device 6 as a software layer running in a server or network service computer or the like is particularly advantageous.

[0041] The number of network access lines 4, 4' is freely scalable according to requirements. In particular, two or more than three network access lines 4, 4' can be provided. Furthermore, it is possible to couple either the auxiliary transmitting device 5 or the auxiliary receiving device 6 to the network 3 with only one network access line 4, 4'. Finally, the number of network access lines 4 can differ from the number of network access lines 4'. For example, the number of network access lines 4 can be one, two, three, or four, and the number of network access lines 4' can be two or three or four, one or three or four, one or two or four, or one or two or three.

[0042] In principle, the network access line(s) 4' should be able to accommodate at least the data throughput of all network access lines 4. Since the network access lines 4 are usually dial-up connections with limited data throughput, such as DSL or UMTS connections from computers at decentralized locations, a single network access line 4' in the form of a gigabyte LAN or a connection to an Internet backbone may be sufficient.

[0043] The roles of transmitting device 1 and receiving device 2 are interchangeable, meaning data transmission can also occur in the opposite direction. In particular, the auxiliary transmitting device 5 can also handle a data stream in the opposite direction, i.e., receive it. The same applies to the auxiliary receiving device 6, which can also transmit a data stream. This enables a bidirectional connection via bundled data access lines 4 and / or 4'. B. Inventive method

[0044] The method according to the invention is explained below purely by way of example using the TCP / IP protocol in a preferred embodiment.

[0045] The data transmission between transmitting device 1 and receiving device 2 is described with reference to Fig. 3 illustrated, in which the designations "SYN", "ACK" and "FIN" originating from the TCP / IP protocol designate packets for connection establishment, confirmation of receipt and connection termination, respectively, and the transmitting device 1 is designated as the client, the transmitting auxiliary device 5 as router A, the network 3 as the Internet, the transmitting auxiliary device 6 as router B and the receiving device 2 as the server.

[0046] To establish an end-to-end connection between transmitting device 1 and receiving device 2, transmitting device 1 sends a SYN packet to receiving device 2 (line 1 in Fig. 3). Since the auxiliary transmitting device 5 simulating the receiving device 2 cannot yet know at this point whether the receiving device 2 is reachable and will agree to the connection establishment, no confirmation of receipt is simulated for the data packets required to establish the connection, nor is any intermediate storage performed. The data packets are encrypted and encapsulated without confirmation in the auxiliary transmitting device 5 and forwarded via any of the network access lines 4 connected thereto, the network 3, and the network access lines 4' to the auxiliary receiving device 6, which in turn forwards the decapsulated and decrypted data packet to the receiving device 2.

[0047] If the receiving device 2 agrees to establish the connection, it sends back an ACK packet (line 2 in Fig. 3), which, like the SYN packet, is forwarded directly back to the transmitting device 1 by the receiving auxiliary device 6 and the transmitting auxiliary device 5.

[0048] The transmitting device 1 confirms the receipt of the ACK packet with an ACK packet (TCP three-way handshake). The end-to-end connection between the transmitting device 1 and the receiving device 2 is thus established. Together with the ACK packet, the transmitting device 1 can already transmit data (line 3 in Fig. 3 ).

[0049] At this point, a buffer integrated in the transmission auxiliary device 5 is activated. The received data packet ai is temporarily stored in the transmission auxiliary device 5. The transmission auxiliary device 5 generates a receipt confirmation for the received data packet ai and sends it via line 7 to the transmission device 1 (line 4 in Fig. 3 ).

[0050] Then (line 5 in Fig. 3) the data packet ai is encrypted and encapsulated in the auxiliary transmitting device 5 as f(ai ) and sent via the network 3 to the auxiliary receiving device 6, which now also activates its buffering. At this point in time, the sending and receiving points of the TCP / IP protocol are decoupled. The auxiliary transmitting device 5 can therefore send the encapsulated data packet via any of the network access lines 4 as A i , B i or C i and distribute further following data packets ai after encryption and encapsulation to other network access lines 4 so that they are transmitted in parallel, wherein the actual bandwidth and utilization of the network access lines 4 is expediently taken into account in order to optimize the transmission. The data packets A i , B i , C i are decapsulated upon arrival at the auxiliary receiving device 6, decrypted if necessary and correctly sorted so that the data packets ai are received back.

[0051] As soon as data packets ai are present in the order expected by the receiving device 2, they are forwarded to the receiving device 2 (line 6 in Fig. 3 ).

[0052] The receiving device 2 confirms the receipt of these data packets ai with an ACK packet (line 7 in Fig. 3 ). The ACK packet is sent via line 7' to the receiving auxiliary device 6. Since the transmitting device 1 has already (line 4 in Fig. 3 ) has received an ACK packet for the data packet ai from the transmitting auxiliary device 5, the receiving auxiliary device 6 does not need to further process the ACK packet coming from the receiving device 2, but can discard it if necessary after internal knowledge.

[0053] As soon as the transmitting device 1 sends the ACK packet (line 4 in Fig. 3 ), it immediately sends the next data packet a i+1 (line 6 in Fig. 3), even before the previous data packet ai has actually arrived at the receiving device 2. The method according to the invention ensures that the transmitting device 1 can continuously send further data packets ai at a high transmission rate. In addition to the effect that this decoupling enables parallel transmission of data over multiple network access lines, the transmission is accelerated and optimized because the transmitting device 1 does not have to pause transmission by waiting for acknowledgments (ACK) from a possibly distant receiving device 2. As an additional effect, the technical limitations of the TCP protocol in the form of the maximum amount of data that may be sent without receiving an acknowledgment of receipt are circumvented.

[0054] When all data of a data stream a have been transmitted in the form of data packets ai by the transmitting device 1 via line 7 to the auxiliary transmitting device 5, the connection can be terminated. For this purpose, a FIN packet is sent from the transmitting device 1 to the auxiliary transmitting device 5 (line 11 in Fig. 3 ).

[0055] Such a FIN packet is sent like the SYN packet (line 1 in Fig. 3 ) is forwarded from the transmitting auxiliary device 1 to the receiving auxiliary device 6. There, the FIN packet is buffered (line 12 in Fig. 3 ).

[0056] Only after the receiving auxiliary device 6 has received all outstanding data packets A i , B i , C i from the transmitting auxiliary device 5, and expediently only after the receiving device 2 has received and confirmed all data packets ai still temporarily stored, decapsulated and decrypted in the receiving auxiliary device 6, the FIN packet temporarily stored in the receiving auxiliary device 6 is forwarded to the receiving device 2 and the internal packet buffering for this connection is deactivated.

[0057] The receiving device 2 now confirms the FIN packet with a FIN-ACK packet. The FIN-ACK packet is then forwarded by the receiving auxiliary device 6 to the transmitting device 1 via the transmitting auxiliary device 6 without processing and without a simulated acknowledgement (line 13 in Fig. 3 ).

[0058] The transmitting device 1 confirms receipt with an ACK packet, which is forwarded unprocessed via the transmitting auxiliary device 5 and the receiving auxiliary device 6 to the receiving device 2 (line 14 in Fig. 3 ).

[0059] The end-to-end connection between the transmitting device 1 and the receiving device 2 is thus closed.

[0060] Once buffering has been activated, both the auxiliary transmitting device 5 and the auxiliary receiving device 6 are capable of buffering and reordering data packets ai as desired. This enables the auxiliary transmitting device 5 to distribute incoming data packets ai from the transmitting device 1 to connected network access lines 4 as desired. As a result, the data packets ai arrive at the auxiliary receiving device 6 in the wrong order. However, they are buffered and reordered there until data packets ai are available in the order expected by the auxiliary receiving device 2. Only then are the data packets ai forwarded to the auxiliary receiving device 2.

[0061] This enables the bundled transmission of individual data streams a over several network access lines 4 and / or 4'.

[0062] Should one of the network access lines 4, 4' used fail during transmission between the auxiliary transmitting device 5 and the auxiliary receiving device 6, the auxiliary transmitting device 5 retransmits the lost data packets to the auxiliary receiving device 6 via another of the network access lines 4. The protocol used for this purpose between the auxiliary transmitting device 5 and the auxiliary receiving device 6 is interchangeable and will not be described further here. The failure of one of the bundled network access lines 4, 4' therefore does not cause the end-to-end connection between the auxiliary transmitting device 5 and the auxiliary receiving device 6, and between the auxiliary transmitting device 1 and the auxiliary receiving device 2, as long as at least one network access line 4 and one network access line 4' remain functional. C. Auxiliary transmission device

[0063] The following is based on reference to Fig. 3An embodiment of the auxiliary transmitting device 5 is described. Since the auxiliary transmitting device 5 can assume the function of the auxiliary receiving device 6 when the data flow direction is reversed, and vice versa, the following also applies to the auxiliary receiving device 6; this can also be configured identically.

[0064] The illustrated auxiliary transmission device 5 is implemented in the form of a hardware router. It comprises a housing 8 in which a mainboard 9 with a processor 10, RAM 11, and non-volatile memory 12 is arranged. The above-described inventive method is implemented in software on the mainboard 9. A so-called "backplane" board 13 connected to the mainboard 9 provides interfaces between the mainboard 9 and communication modules 14, which can be inserted into slots 15 of the housing 8. The communication modules 14 can be configured for the same or different network access lines 4. For example, one communication module 14 can be configured for a DSL network access line, while another communication module 14 is configured for an ISDN network access line, and yet another communication module 14 is configured for a WLAN network access line.The communication modules 14 each have a conveniently hot-pluggable connector 16 in order to be inserted into or removed from the backplane board 13 when the auxiliary transmission device 5 is switched on.

[0065] The communication modules 14 have suitable connection devices 17, for example in the form of sockets, for connection to a corresponding network access line.

[0066] Furthermore, a LAN socket 18 or the like is expediently provided in the housing, which is connected to the main board 9. Via this LAN socket 18, the auxiliary transmission device 5 can be connected to the line 7 ( Fig. 1 ), especially a LAN.

[0067] A data packet ai, which arrives via line 7 and is to be transmitted via bundled network access lines 4 to the auxiliary receiving device 6, reaches the auxiliary transmitting device 5 via the LAN socket 18 and is routed to the main board 9. The main board 9 already confirms at this time that the data packet ai has not yet arrived at the receiver by sending a confirmation packet via the LAN socket 8. The data packet ai is then encrypted, adapted by encapsulation to the transmission protocol of the network 3 used between the auxiliary transmitting device 5 and the auxiliary receiving device 6, and routed to one of the communication modules 14. The selection is expediently made taking into account the readiness of the corresponding communication module 14 (cable connected, network connection established) and its current load.The communication module 14 receives the encapsulated data packet and sends it via the corresponding network access line 4.

[0068] The network access line 4 terminates at the internet backbone of the line provider, i.e., at network 3. From here, the data packets A i , B i , C i are forwarded like regular IP data packets to the receiving auxiliary device 6. There, they are decapsulated, sorted into the correct order, decrypted, and reassembled into the original data stream a. The original data stream a is then output to the receiving device 2 via the LAN socket of the receiving auxiliary device 6, which can be configured in the same way as the transmitting auxiliary device 5, via line 7'.

[0069] The method executed on the mainboard 9 can also be executed directly in the transmitting device 1 and / or the receiving device 2. For this purpose, the auxiliary transmitting device 5 and / or the auxiliary receiving device 6 is a plug-in card or a software layer for a PC or server or the like. In the case of the software layer, the transmitting device 1 or the receiving device 2 has the connection devices 17, e.g., directly on the motherboard or in the form of DSL or WLAN expansion cards for a PC. The method according to the invention is then executed as a program layer on the PC.In the transmitting device 1, it is implemented as a layer separate from the layer for TCP / IP transmission, which receives data from the TCP / IP layer, confirms receipt of the data packets ai to the TCP / IP layer, encrypts the data packets ai, packages them, divides them into at least two data streams A, B, and assigns each of the data streams A, B to one of the network access lines 4. The same applies analogously to the receiving device 2, in which the auxiliary receiving device 6 can be implemented as a layer separate from the layer for TCP / IP transmission. LIST OF REFERENCE SYMBOLS

[0070] 1Transmitter 2Receiver 3Network 4, 4'Network access line 5Transmitter auxiliary device 6Receiver auxiliary device 7, 7'Line 8Housing 9Mainboard 10Processor 11RAM 12Non-volatile memory 13Backplane board 14Communication module 15Slot 16Connector 17Connector 18LAN socket

Claims

1. A transmission auxiliary device (5) designed for forwarding an input data stream (a), which can be supplied from a transmission end point, is intended for a reception end point to be reached via a reception auxiliary device and contains successive data packets (ai), to a plurality of bundled network access lines (4) of different physical line types, namely wireless and wired network access lines, by distributing the data packets (ai) of the input data stream (a) to the network access lines (4), wherein the transmission auxiliary device (5) is designed for encapsulating the data packets (ai) of the input data stream (a) into data packets (Ai, Bi, Ci) of output data streams (A, B, C) for the network access lines (4), the transmission auxiliary device being designed for asynchronous bundling of these network access lines which differ in terms of bandwidth and / or delay.

2. Transmission auxiliary device according to claim 1, characterized in that the transmission auxiliary device (5) is designed for encrypting the data packets (ai) before encapsulation.

3. Auxiliary receiving device (6) designed for assembling data packets (Ai, Bi, Ci ) which can be received in a distributed manner via a plurality of bundled network access lines (4) of different physical line types, namely wireless and wired network access lines, into a corresponding data stream (a) for a receiving endpoint, wherein the receiving auxiliary device (6) is designed to decapsulate the data packets (Ai, Bi, Ci) in order to recover corresponding data packets (ai) of the data stream (a) originating from a transmitting endpoint and transmitted by a transmitting auxiliary device, wherein the network access lines differing in bandwidth and / or delay are asynchronously bundled.

4. Auxiliary receiving device according to claim 3, characterized in that the auxiliary receiving device (6) is designed for buffering the decapsulated data packets (ai)5. Auxiliary receiving device according to claim 3 or 4, characterized in that the auxiliary receiving device (6) is designed for sorting the decapsulated data packets (ai).

6. Receiving auxiliary device according to one of claims 3 to 5, characterized in that the receiving auxiliary device (6) is designed to forward decapsulated data packets (ai) in the order expected by the receiving endpoint.

7. A receiving auxiliary device according to any one of claims 3 to 6, characterized in that the receiving auxiliary device (6) is configured to discard the receiving acknowledgements from the receiving endpoint.

8. Arrangement for transmitting a data stream (a) between two ends of an end-to-end connection from a transmitting device (1) to a receiving device (2) via a network (3) with a packet-based transmission protocol, in particular via the TCP / IP-based Internet, wherein the transmitting device (1) and the receiving device (2) are connected to the network via network access lines (4, 4') of different physical line types, namely wireless and wired network access lines, and a plurality of network access lines (4, 4') are provided on the transmitting and / or receiving device side for asynchronous bundling, wherein a transmission auxiliary device (5) according to claim 1 or 2 is interposed between the transmitting device (1) and the network access line(s) (4), which is provided for encapsulating data packets (ai) of the data stream (a) transmitted by the transmitting device (1) and for distributed transmission of the encapsulated data packets (Ai, Bi, Ci) to the network (3) via the network access line(s) (4) differing in bandwidth and / or delay, and a receiving auxiliary device (6) interposed between the network access line(s) (4') and the receiving device (2) according to one of claims 3 to 7, which is designed to receive and decapsulate the encapsulated data packets (Ai, Bi, Ci) and to forward the decapsulated data packets (ai) in the order of the data stream (a) to the receiving device (2), the transmission auxiliary device being designed for asynchronous bundling of these network access lines which differ in terms of bandwidth and / or delay.

9. Arrangement according to claim 8, characterized in that the network access lines (4, 4') are addressed via unique addresses.

10. Arrangement according to claim 8 or 9, characterized in that a network access line (4) on the transmitting-aid device side is connected to a network access line (4') on the receiving-aid device side via an end-to-end connection.

11. Arrangement according to one of claims 8 to 10, characterized in that a network access line (4') is provided on the receiving device side.

12. Method for transmitting a data stream (a) between two ends of an end-to-end connection from a transmitting device (1) to a receiving device (2) via a network (3) with packet-based transmission protocol, in particular via the TCP / IP-based Internet, by means of the arrangement according to one of claims 8 to 10, wherein the transmitting device (1) is connected to the network by means of a transmitting auxiliary device (5) and the receiving device (2) is connected to the network by means of a receiving auxiliary device (6) via network access lines (4, 4') of different physical line types, namely wireless and wired network access lines, and a plurality of these network access lines (4, 4'), which differ in terms of bandwidth and / or transit time, are provided on the transmitting and / or receiving device side for asynchronous bundling, wherein data packets (ai) of the data stream (a) transmitted by the transmitting device (1) are encapsulated and the encapsulated data packets (Ai, Bi, Ci) are transmitted to the network (3) in a distributed manner via the network access line(s) (4) and are retrieved from the network (3) via the network access line(s) (4'), decapsulated and forwarded to the receiving device (2) in the sequence of the data stream (a).

13. Method claim 12, characterized in that the network access lines (4, 4') are addressed via unique addresses.

14. Method according to claim 12 or 13, characterized in that a network access line (4) on the transmitting-aid device side is connected to a network access line (4') on the receiving-aid device side via an end-to-end connection.

15. Method according to one of claims 12 to 14, characterized in that the data packets (ai) of the incoming data stream (a) are distributed to outgoing data streams (A, B, C) and exactly one of the network access lines (4) is assigned to each outgoing data stream (A, B, C).

16. Method according to claim 15, characterized in that a data stream (A) whose network access line (4) has more bandwidth at a point in time than the network access line (4) of another data stream (B) receives more data packets (Ai) at this point in time than the other data stream (B).

17. Method according to any one of claims 12 to 16, characterized in that when a network access line (4, 4') breaks down, the transmitting auxiliary device (5) retransmits the lost data packets to the receiving auxiliary device (6) via another one of the network access lines (4).

18. A transmission method for a transmission auxiliary device according to claim 1 or 2, for forwarding an input data stream (a) deliverable from a transmission endpoint to a reception endpoint via a reception auxiliary device and comprising successive data packets (ai) to a plurality of network access lines (4) of different physical line types, namely wireless and wired network access lines, by distributing the data packets (ai) of the input data stream (a) to the network access lines (4), wherein the data packets (ai) of the input data stream (a) are encapsulated into data packets (Ai, Bi, Ci) which are forwarded as output data streams (A, B, C) distributed to the network access lines (4), wherein several of these network access lines differing in bandwidth and / or propagation time are bundled asynchronously.

19. The transmission method according to claim 18, characterized in that a receipt acknowledgement signaling the receipt of a data packet (ai) by the receiving endpoint is generated before forwarding the corresponding encapsulated data packet.

20. Transmission method according to claim 18 or 19, characterized in that the data packets (ai) are encrypted before encapsulation.

21. A receiving method for a receiving auxiliary device according to any one of claims 3 to 7, for assembling data packets (Ai, Bi, Ci) receivable in a distributed manner over a plurality of bundled network access lines (4) of different physical line types, namely wireless and wired network access lines, into a corresponding data stream (a) for a receiving endpoint, wherein the data packets (Ai, Bi, Ci) are decapsulated to recover corresponding data packets (ai) of the data stream (a) originating from a transmitting endpoint and transmitted by a transmitting auxiliary device, wherein a plurality of said network access lines differing in bandwidth and / or transmission time are asynchronously bundled.

22. Receiving method according to claim 21, characterized in that the decapsulated data packets (ai) are temporarily stored and sorted.

23. Receiving method according to claim 21 or 22, characterized in that the decapsulated data packets (ai) are forwarded in the order expected by the receiving endpoint.

24. A receiving method according to any one of claims 21 to 23, characterized in that acknowledgements of receipt from the receiving endpoint are not forwarded to the transmitting endpoint.

25. A computer program product comprising instructions which, when the method is executed by a computer, cause the computer to execute the method of any one of claims 12 to 24