WO2014117359A1

WO2014117359A1 - Method and device for processing packet loss feedback message

Info

Publication number: WO2014117359A1
Application number: PCT/CN2013/071193
Authority: WO
Inventors: 王立波
Original assignee: 华为技术有限公司
Priority date: 2013-01-31
Filing date: 2013-01-31
Publication date: 2014-08-07
Also published as: CN104137507B; CN104137507A

Abstract

The present invention relates to a method and a device for processing a packet loss feedback message. The processing method comprises: an RLC device receiving a TCP data packet sent by a TCP device, assembling the TCP data packet to form an RLC data packet, and sending the RLC data packet to a peer device; the RLC device receiving a response message of the RLC data packet returned by the peer device; the RLC device constructing a response message of the TCP data packet corresponding to the RLC data packet according to the response message of the RLC data packet; and the RLC device feeding back the response message of the TCP data packet to the TCP device. The present invention can accurately determine whether TCP packet loss occurs, and obtain accurate TCP packet loss information, so that the specific data packet that gets lost can be figured out.

Description

Message processing method and device for feedback packet loss

Technical field

The present invention relates to the field of wireless communication technologies, and in particular, to a message processing and device for feedback packet loss. Background technique

Transmission Control Protocol (TCP) is the most widely used transmission protocol on the Internet, but its original design goal is to work in a wired network. Therefore, there is a section of wireless air interface in the TCP connection (ie, wireless TCP). At the time, the TCP protocol involved in the wired network is no longer able to guarantee efficient work.

In a wired network, the TCP protocol controls the congestion of the transmission by introducing a control mechanism for the congestion window of the sender. The receiving end notifies the sending end of its current receiving window size, and the transmitting end determines how much data the transmitting end can send to the receiving end according to the size of the receiving window and the size of the congestion window, that is, the value of the real sending window is a congestion window. And the minimum value in the notification window. This prevents the sender from sending too much data without causing TCP buffer overflow at the receiving end and reducing the rate of congestion in the network.

Radio network controller in the third generation mobile communication technology (3 ^Id Genera ion, 3G)

Network Control ler, RNC) or fourth generation mobile communication technology ^{(3 rd Genera t ion, 3G} ) evolved base station (evolut ion NodeB, eNodeB), there may be a corresponding TCP or TCP proxy function entity for the radio TCP accelerates. On the radio side of a terminal with a TCP proxy function or a TCP entity, due to air interface packet loss and non-sequential delivery, the receiver receives a large number of out-of-order packets. Usually, after receiving the out-of-order packet, the receiving end will send multiple duplicate acknowledgements (Dup acknowledgement, Dup ACK) or send selective acknowledgement (Selec t acknowledgement, SACK) to the sender, indicating that a packet is lost.

Since the SACK is required in the scheme for sending SACK, the SACK option is supported. If the SACK option is not supported by the receiver, the scheme cannot be used. Therefore, most of the existing packet loss judging methods adopt a scheme of transmitting Dup ACK. When the sender receives the Dup ACK, the congestion window will decrease, generally decreasing to the threshold of the slow start; and the sender will start a timer after sending a packet. Within the time range of this timer, if the acknowledgment of this packet (acknowl edgemenmen t , ACK ) has not been received, the congestion window will be reduced to 1.

Therefore, the control of the congestion window is crucial in the TCP protocol, and many existing algorithms are given for adjusting the congestion window of TCP. The most common algorithm is to determine whether packet loss is possible based on the estimated bandwidth and the bandwidth corresponding to the congestion window. A judgment is made on the current network state, and the result of this state judgment may be congestion and non-congestion. In the case of congestion, if a duplicate ACK occurs, or RT0 times out, the current congestion window is modified while retransmitting the data packet; if there is no congestion, if a duplicate ACK occurs, or When RT0 times out, the size of the current congestion window is maintained while retransmitting the data packet, and the problem of insufficient utilization of the wireless air interface caused by the congestion window being adjusted too small is avoided. However, the existing algorithm is based on the current TCP link bandwidth estimation. In the case of an error in the current TCP link bandwidth estimation, the judgment of packet loss is inaccurate and cannot be distinguished. In the case of packet loss and congestion, in addition, it is not clear which packet is specifically lost. Summary of the invention

It is an object of the present invention to provide a message processing and apparatus for feedback packet loss, which can accurately determine whether TCP packet loss has occurred.

To achieve the above objective, a first aspect of the present invention provides a radio link control RLC apparatus, including: a processor, a first interface, and a second interface;

The first interface is configured to interact with a transmission control protocol TCP device;

The second interface is configured to interact with the peer device; The processor is used to:

Receiving, by the first interface, a TCP data packet sent by the TCP device;

Grouping the TCP data packet into an RLC data packet;

Sending, by the second interface, the RLC data packet to the peer device;

Receiving, by the second interface, a response message of the RLC data packet returned by the peer device;

Constructing a response message of the TCP packet corresponding to the RLC data packet according to the response message of the RLC data packet;

Sending a response message of the TCP packet to the TCP device through the first interface. With reference to the first aspect, in a first possible implementation manner of the first aspect, the TCP packet received by the first interface carries information of a TCP packet, where the information of the TCP packet includes the following One or any combination: IP address, port and byte range;

The processor is configured to form the TCP packet into an RLC data packet, and specifically includes: the processor is configured to:

Identifying the TCP packet according to the information of the TCP packet, and recording the

The identifier of the TCP packet;

Performing an RLC group packet on the TCP packet to form an RLC data packet, and identifying the RLC data packet;

And establishing, according to the identifier of the TCP data packet and the identifier of the RLC data packet, a correspondence between the RLC data packet and the TCP data packet.

With reference to the first possible implementation manner of the first aspect, in a second possible implementation manner of the first aspect, the processor is configured to construct, according to the response message of the RLC data packet, a TCP corresponding to the RLC data packet The response message of the packet, including:

The processor is used to:

And according to the response message of the RLC data packet, the response message of the TCP data packet is constructed by using the correspondence between the RLC data packet and the TCP data packet. With reference to the first aspect, in a third possible implementation manner of the first aspect, the response message of the RLC data packet is an RLC acknowledgement ACK information, where the processor is configured to construct the message according to the response message of the RLC data packet. The response message of the TCP packet corresponding to the RLC data packet specifically includes: the processor is configured to construct TCP ACK information of the TCP data packet according to the RLC ACK information. In conjunction with the third possible implementation of the first aspect, in a fourth possible implementation of the first aspect, the processor is further configured to:

Receiving TCP ACK information fed back by the peer device by using the second interface;

Comparing the TCP ACK information fed back by the peer device with the constructed TCP ACK information, if not, it is determined that the TCP packet is lost when being sent to the TCP device of the peer device.

In conjunction with the fourth possible implementation of the first aspect, in a fifth possible implementation manner of the first aspect, when a packet loss occurs, the processor is further configured to:

Determining a TCP packet in which packet loss occurs according to the TCP ACK information and the RLC ACK information fed back by the peer device;

And instructing the TCP device to retransmit the TCP packet with the packet loss or send the RLC packet corresponding to the TCP packet with the packet loss through the second interface.

In conjunction with the third possible implementation of the first aspect, in a sixth possible implementation of the first aspect, the processor is further configured to:

Comparing the TCP ACK information fed back by the peer device with the constructed TCP ACK information, if they are consistent, determining that no packet loss occurs, and not sending the TCP fed back by the peer device to the TCP device. ACK information.

With reference to the first aspect, in a seventh possible implementation manner of the first aspect, the response message of the RLC data packet is an RLC negative acknowledgement NACK information, and the processor is configured to construct a response message according to the RLC data packet. The response message of the TCP packet corresponding to the RLC data packet specifically includes: the processor is configured to construct a TCP NACK message of the TCP data packet according to the RLC NACK information. And indicating that the TCP device retransmits the TCP packet corresponding to the TCP NACK information.

With reference to the seventh possible implementation of the first aspect, in an eighth possible implementation manner of the first aspect, the processor is configured to construct TCP NACK information of the TCP data packet according to the RLC NACK information, specifically:

The processor is used to:

Retransmitting the RLC data packet of the RLC data packet to the peer device, and starting an RLC retransmission timer and/or an RLC retransmission counter;

The TCP NACK information is constructed according to the RLC NACK information when the count value of the RLC retransmission timer and/or the RLC retransmission counter exceeds a preset threshold.

In conjunction with the first aspect, in a ninth possible implementation manner of the first aspect, the response message of the TCP packet is selectively acknowledged by a user plane GPRS tunneling protocol GTP-U extension header or TCP

SACK option to pass.

In conjunction with the first aspect, in a tenth possible implementation manner of the first aspect, the RLC device is a radio network controller RNC or an evolved base station eNodeB.

In a second aspect, a TCP device is provided, including: a processor and a communication interface;

The communication interface is configured to interact with an RLC device;

The processor is used to:

Receiving, by the communication interface, TCP NACK information sent by the RLC device, where the TCP NACK information is configured by the RLC device according to the RLC NACK information;

The TCP packet of the lost packet is determined according to the TCP NACK information.

With reference to the second aspect, in a first possible implementation manner of the second aspect, after determining that the packet is lost, the processor is further configured to:

Retransmitting the lost TCP packet to the peer device through the communication interface, and starting a TCP retransmission timer and/or a TCP retransmission counter;

When the count value of the TCP retransmission timer and/or the TCP retransmission counter exceeds a preset threshold, the congestion window value of the transmitting end is reduced. With reference to the second aspect, in a second possible implementation manner of the second aspect, the TCP device is an RNC, an eNodeB, a GGSN, an SGSN, or a PGW.

In a third aspect, a base station device is provided, including: an RLC device and a TCP device according to an embodiment of the present invention.

A fourth aspect provides a message processing method for feedback packet loss, where the method includes: a radio link control RLC device receives a TCP packet sent by a TCP device of a transmission control protocol, and forms a packet of the TCP packet to form an RLC data. Packet, and sending the RLC data packet to the peer device;

The RLC device receives a response message of the RLC data packet returned by the peer device; the RLC device constructs a response message of the TCP data packet corresponding to the RLC data packet according to the response message of the RLC data packet;

The RLC device feeds back a response message of the TCP packet to the TCP device.

With reference to the fourth aspect, in a first possible implementation manner of the fourth aspect, the TCP data packet received by the RLC device carries information of a TCP data packet, where the information of the TCP data packet includes the following: One or any combination of: IP address, port, and byte range;

The grouping the TCP data packet into an RLC data packet includes:

The RLC device identifies the TCP data packet according to the information of the TCP data packet, and records an identifier of the TCP data packet;

And the RLC device performs an RLC group packet on the TCP data packet to form an RLC data packet, and identifies the RLC data packet;

And the RLC device establishes and records a correspondence between the RLC data packet and the TCP data packet according to the identifier of the TCP data packet and the identifier of the RLC data packet.

With reference to the first possible implementation manner of the fourth aspect, in a second possible implementation manner of the fourth aspect, the responding message of the TCP data packet is configured according to the response message of the RLC data packet, specifically:

Determining the RLC data packet and the TCP data packet according to the response message of the RLC data packet Corresponding relationship, constructing a response message of the TCP packet.

With reference to the fourth aspect, in a third possible implementation manner of the fourth aspect, the response message of the RLC data packet is RLC ACK information;

The constructing a response message of the TCP packet according to the response message of the RLC data packet, specifically:

The TCP ACK information of the TCP packet is constructed based on the RLC ACK information.

With the third possible implementation of the fourth aspect, in a fourth possible implementation manner of the fourth aspect, after the RLC device feeds back the response message of the TCP packet to the TCP device, Includes:

Receiving, by the RLC device, TCP ACK information fed back by the peer device;

The RLC device compares the TCP ACK information fed back by the peer device with the constructed TCP ACK information, and if not, determines that the data packet is lost when sent to the TCP device of the peer device. package.

With the fourth possible implementation of the fourth aspect, in a fifth possible implementation manner of the fourth aspect, when a packet loss occurs, the method further includes:

Determining, by the RLC device, the TCP packet that is lost according to the TCP ACK information and the RLC ACK information fed back by the peer device;

The RLC device instructs the TCP device to retransmit the TCP packet in which the packet loss occurs or to send the RLC packet corresponding to the TCP packet in which the packet loss occurs.

With the third possible implementation of the fourth aspect, in a sixth possible implementation manner of the fourth aspect, after the RLC device feeds back the response message of the TCP packet to the TCP device, Includes:

Receiving, by the RLC device, TCP ACK information fed back by the peer device;

The RLC device compares the TCP ACK information fed back by the peer device with the constructed TCP ACK information. If they are consistent, it is determined that no packet loss occurs, and the peer device is no longer sent to the TCP device. TCP ACK information fed back by the device. With reference to the fourth aspect, in a seventh possible implementation manner of the fourth aspect, the response message of the RLC data packet is RLC NACK information;

And constructing TCP NACK information of the TCP packet according to the RLC NACK information, to instruct the TCP device to retransmit the TCP packet corresponding to the TCP NACK information.

With reference to the seventh possible implementation manner of the fourth aspect, in the eighth possible implementation manner of the fourth aspect, the configuring the TCP NACK information of the TCP data packet according to the RLC NACK information includes:

In conjunction with the fourth aspect, in a ninth possible implementation manner of the fourth aspect, the response message of the TCP data packet is delivered by using an extension header of the GTP-U or a TCP SACK option.

The fifth aspect provides a message processing method for feedback packet loss, where the method includes: receiving TCP negative acknowledgement NACK information sent by an RLC device, where the TCP NACK information is constructed by the RLC device according to RLC NACK information;

With reference to the fifth aspect, in a first possible implementation manner of the fifth aspect, after the determining, according to the TCP NACK information, the packet loss of the TCP data packet, the method further includes:

Retransmitting the lost TCP packet to the peer device, and starting a TCP retransmission timer and/or a TCP retransmission counter;

When the count value of the TCP retransmission timer and/or the TCP retransmission counter exceeds a preset threshold, the congestion window value of the transmitting end is reduced.

A sixth aspect provides a message processing apparatus for feeding back a packet, where the apparatus includes: a packet unit, configured to receive a TCP data packet sent by the TCP device, group the TCP data packet into an RLC data packet, and send the RLC data packet to the peer device;

a receiving unit, configured to receive a response message of the RLC data packet returned by the RLC data packet sent by the peer device for the group packet unit;

a processing unit, configured to construct, according to the response message of the RLC data packet received by the receiving unit, a response message of a TCP data packet corresponding to the RLC data packet;

And a sending unit, configured to feed back a response message of the TCP packet obtained by the processing unit to the TCP device.

With reference to the sixth aspect, in a first possible implementation manner of the sixth aspect,

a receiving subunit, configured to receive a TCP data packet sent by the TCP device, and obtain information about a TCP data packet carried in the TCP data packet, where the information of the TCP data packet includes one or any combination of the following: IP address, port and byte range;

a recording subunit, configured to identify the TCP data packet according to the information of the TCP data packet obtained by the receiving subunit, and record an identifier of the TCP data packet;

a packet subunit, configured to perform RLC grouping on the TCP packet received by the receiving subunit to form an RLC data packet, and identify the RLC data packet;

a storage subunit, configured to establish and record a correspondence between the RLC data packet and the TCP data packet according to the identifier of the TCP data packet recorded by the recording subunit and the identifier of the RLC data packet obtained by the group packet subunit .

With reference to the first possible implementation manner of the sixth aspect, in a second possible implementation manner of the sixth aspect, the processing unit is specifically configured to use the storage subunit according to the response message of the RLC data packet Corresponding relationship between the recorded RLC data packet and the TCP data packet, constructing a response message of the TCP data packet.

With reference to the sixth aspect, in a third possible implementation manner of the sixth aspect, when the response message of the RLC data packet received by the receiving unit is RLC ACK information, the processing unit is configured according to The RLC ACK information constructs TCP ACK information of a TCP packet.

With reference to the third possible implementation manner of the sixth aspect, in a fourth possible implementation manner of the sixth aspect, the receiving unit is further configured to receive TCP ACK information that is fed back by the peer device; Includes:

a comparing unit, configured to forward the TCP ACK information fed back by the peer device with the constructed TCP

If the ACK information is compared, if it is inconsistent, it is determined that the data packet is lost when it is sent to the TCP device of the peer device.

With reference to the fourth possible implementation manner of the sixth aspect, in a fifth possible implementation manner of the sixth aspect, when the packet loss occurs, the comparing unit is configured according to the TCP ACK information and the RLC fed back by the peer device The ACK information determines a TCP packet in which packet loss occurs; and triggers the sending unit to send an instruction indicating that the TCP device retransmits the TCP packet in which the packet loss occurs or sends the RLC corresponding to the TCP packet in which the packet loss occurs. The instruction of the packet.

With reference to the third possible implementation manner of the sixth aspect, in a sixth possible implementation manner of the sixth aspect, the receiving unit is further configured to receive TCP ACK information that is fed back by the peer device; Includes:

a comparing unit, configured to compare the TCP ACK information fed back by the peer device with the constructed TCP ACK information, if yes, determining that no packet loss occurs, and not triggering the sending unit to the TCP The device sends the TCP ACK information fed back by the peer device.

With reference to the sixth aspect, in a seventh possible implementation manner of the sixth aspect, when the response message of the RLC data packet received by the receiving unit is RLC NACK information, the processing unit is configured according to the RLC NACK information. The TCP NACK information of the TCP packet is configured to instruct the TCP device to retransmit the TCP packet corresponding to the TCP NACK information.

In conjunction with the seventh possible implementation of the sixth aspect, in an eighth possible implementation manner of the sixth aspect, the device further includes:

a first retransmission unit, configured to: when the response message of the RLC data packet received by the receiving unit is RLC NACK information, the response message of the RLC data packet is an RLC of RLC NACK information Retransmitting the data packet to the peer device, and starting an RLC retransmission timer and/or an RLC retransmission counter; when the count value of the RLC retransmission timer and/or the RLC retransmission counter exceeds a preset threshold, Triggering the processing unit to construct TCP NACK information according to the RLC NACK information.

In conjunction with the sixth aspect, in a ninth possible implementation manner of the sixth aspect, the response message of the TCP packet that is sent by the sending unit is transmitted by using an extension header of the GTP-U or a TCP SACK option.

The seventh aspect provides a message processing apparatus for feedback packet loss, where the apparatus includes: a receiving unit, configured to receive TCP negative acknowledgement NACK information sent by the RLC apparatus, where the TCP

The NACK information is constructed by the RLC device according to the RLC NACK information;

a determining unit, configured to determine, according to the TCP NACK information received by the receiving unit, packet loss

TCP packet.

In conjunction with the seventh aspect, in a first possible implementation manner of the seventh aspect, the device further includes:

a second retransmission unit, configured to: after the determining unit determines the TCP packet of the packet loss, retransmit the TCP packet of the packet loss to the peer device, and start a TCP retransmission timer and/or Or TCP retransmission counter;

And an adjusting unit, configured to reduce a congestion window value of the sending end when the count value of the TCP retransmission timer and/or the TCP retransmission counter initiated by the retransmission unit exceeds a preset threshold.

The message processing method and device for feedback packet loss provided by the present invention determine whether a current TCP data packet is correctly received by using ACK/NACK information fed back by a radio link control (RLC) layer. Therefore, the TCP packet loss can be accurately determined and the accurate TCP packet loss information can be obtained. Only the data that is not correctly received can be retransmitted, which can reduce unnecessary retransmission, improve the performance of the wireless TCP, and make full use of the air interface resources. DRAWINGS

FIG. 1 is a flowchart of a message processing method for feedback packet loss according to Embodiment 1 of the present invention; 2 is a flowchart of processing a packet of a TCP packet according to Embodiment 1 of the present invention; FIG. 3 is a schematic diagram of correspondence between protocol layers in an RNC according to Embodiment 1 of the present invention; A flowchart of a message processing method for providing feedback packet loss; FIG. 5 is a flowchart of a method for performing congestion control according to TCP NACK information according to Embodiment 2 of the present invention;

6 is a signaling diagram of a message processing method for feedback packet loss according to Embodiment 3 of the present invention; FIG. 7 is a schematic diagram of an extension header of a GTP-U protocol;

FIG. 8 is a schematic diagram of a message processing apparatus for feedback packet loss according to Embodiment 4 of the present invention; FIG. 9 is a schematic diagram of a message processing apparatus for feedback packet loss according to Embodiment 5 of the present invention; FIG. 10 is a schematic diagram of an RLC apparatus according to Embodiment 6 of the present invention; Schematic diagram of the structure;

FIG. 11 is a schematic structural diagram of a TCP device according to Embodiment 7 of the present invention. detailed description

The technical solution of the present invention will be further described in detail below through the accompanying drawings and embodiments. Third Generation Partnership Project ^{(3 rd Generation Partnership Project, 3GPP} ) began a 3G Long Term Evolution (Long Term Evolution, LTE). In the LTE protocol stack hierarchy, the Radio Link Control (RLC) layer is one of the protocols of the L2 layer of the LTE protocol stack, and is mainly used to provide a reliable data transmission link, which is used for shielding wireless The impact of the link and provide reliable data transmission for the upper layer.

In the current 3G system, the radio access network (RAN) side includes an RNC node and a base station NodeB. The RNC node controls multiple NodeBs, and the NodeB directly communicates with a user equipment (User Equipment, UE). In the current 4G system, the RAN side includes an eNodeB node, and the eNodeB node directly communicates with the Mobility Management Entity (MME) of the core network and the gateway, and simultaneously communicates with the UE.

The message processing method and device for feedback packet loss provided by the present invention are applied to determine the TCP transmission during the process of performing wireless TCP data transmission after establishing a bearer channel between the RAN side and the UE side. Whether the packet has been dropped.

Embodiment 1

FIG. 1 is a flowchart of a message processing method for feedback packet loss according to the embodiment. As shown in FIG. 1, the method includes:

The S1 0 RLC device receives the TCP packet sent by the TCP device, forms the TCP packet into an RLC packet, and sends the RLC packet to the peer device.

The TCP packet received by the RLC device may be a processed TCP packet (such as a packet processed by another protocol layer) or a TCP packet sent by the TCP device. The peer device is usually a UE. The specific processing will be described in the following pages in conjunction with Figs. 2 and 3.

S102: The RLC device receives a response message of the RLC data packet returned by the peer device. The RLC device corresponding to the peer device returns the response information of the corresponding RLC packet for each RLC packet. The response information of the RLC packet may include RLC ACK information and/or RLC NACK information.

51. The RLC device constructs a response message of the TCP packet corresponding to the RLC data packet according to the response message of the RLC data packet.

If the response message of an RLC packet is ACK, the response message of the TCP packet corresponding to the RLC packet is ACK. If the response message of an RLC packet is NACK, the response message of the TCP packet corresponding to the RLC packet is NACK. Using this correspondence, a response message of the TCP packet is constructed based on the response message of the RLC packet, that is, the TCP ACK information is constructed using the RLC ACK information, and the TCP NACK information is constructed using the RLC NACK information.

51. The RLC device feeds back the response message of the TCP packet to the TCP device. The TCP device determines whether the TCP packet is lost according to a response message of the TCP packet. when

When the RLC device transmits the TCP NACK information, the TCP device determines that the TCP packet has been dropped. When the TCP device receives an ACK of a TCP packet, it determines that no packet loss has occurred in the TCP packet.

FIG. 2 is a flowchart of processing a packet for a TCP packet according to the embodiment. As shown in FIG. 2, the process includes: The S101 RLC device receives the TCP packet sent by the TCP device and obtains information of the TCP packet carried in the TCP packet.

In the data transmission process between the RAN side and the UE side, the transmitting end may be the RAN side, the receiving end may be the UE, and the RLC device and the TCP device are equally provided on the RAN side and the UE side. In the actual application scenario, the TCP packet sent by the TCP device at the transmitting end usually performs pre-processing such as header compression and packet parsing through other protocol layers before reaching the RLC device, and the RLC device receives the processed TCP data. package.

FIG. 3 is a schematic diagram of correspondence between protocol layers in an RNC. As shown in FIG. 3, a TCP proxy server performs data transmission through a RNC and a base station NodeB. TCP Proxy Server Includes multiple TCP connections for multiple users. The RNC may include a Packet Data Convergence Protocol (PDCP) layer, an RLC device (ie, an RLC layer), a dedicated media access control (Media Acces s Cont ro l-D, MACD) layer, and media. Access control service (Med ia Acces s Cont ro l C li ent) layer. The RNC receives the TCP data packet sent from the user's multiple TCP connections through the PDCP layer, and the PDCP layer parses the TCP data packet to obtain information of the TCP data packet, and the information of the TCP data packet includes one or any of the following. Combination: IP address, port and byte range, used to identify the TCP packet based on the information of the TCP packet. The PDCP layer also has a header compression function that passes the header-compressed TCP packets to the RLC device. The MAC layer performs scheduling on the RLC packets sent by the RLC device, and the MACC layer is used to aggregate and send the services in the cell to the NodeB.

If the RLC device receives the TCP packet sent by the TCP device at the transmitting end,

The TCP packet is parsed to obtain the information of the TCP packet, and the parsed TCP packet is sent to the PDCP layer for header compression processing, and the RLC device supplies the packet processed by the PDCP layer to S1012.

The SI 012, the RLC device identifies the TCP packet according to the information of the TCP packet, and records the identifier of the TCP packet.

Correspondingly, the identifier of the data packet includes one or any of the information of the TCP packets listed below. Combination: IP address, port and byte range.

51 01 3. The RLC device performs RLC grouping on the data packet to form an RLC data packet, and identifies the RLC data packet.

In the actual application scenario, when the RLC device sends the identified RLC data packet to the peer device, the processed RLC data packet may be sent to the peer device through other protocol layers, for example, sent through the MACD layer in FIG. At this time, the RLC device determines the size of the packet according to the scheduling of the MACD layer, and how much data is sent to the MACD layer for traffic control, thereby avoiding congestion of the IuB port between the RNC and the NodeB.

51. The RLC device establishes and records a correspondence between the RLC data packet and the TCP data packet according to the identifier of the data packet and the identifier of the RLC data packet.

The correspondence between the RLC data packet and the TCP data packet is one of the following three types: one of the TCP data packets corresponds to one of the RLC data packets; one of the TCP data packets corresponds to multiple of the RLC data packets; or, multiple The TCP data packet corresponds to one of the RLC data packets.

In S 1 03, a response message of the TCP packet is constructed according to the correspondence between the RLC packet and the TCP packet.

Specifically, if a TCP packet corresponds to only one RLC packet, the ACK of the RLC packet is an ACK of the TCP packet. If a TCP packet corresponds to multiple RLC packets, if the ACK of multiple RLC packets is received, then the TCP packet can be considered as ACK, that is, multiple RLC packets are required to be ACK. If multiple TCP packets correspond to one RLC packet, the ACK of the RLC packet is the ACK of multiple TCP packets.

Through the message feedback of the RLC device, the present invention can accurately determine whether TCP packet loss has occurred, and can obtain accurate TCP packet loss information, and clarify which data packet is specifically lost, and can efficiently perform data retransmission.

Embodiment 2

FIG. 4 is a flowchart of a message processing method for feedback packet loss according to the embodiment. As shown in FIG. 4, the method includes: The S20 TCP device receives a response message of the TCP packet sent by the RLC device at the transmitting end. The response message of the TCP packet is obtained by the method of Embodiment 1, and details are not described herein again.

5202. The TCP device determines, according to the response message of the TCP packet, whether the corresponding TCP packet is lost. When it is determined that the TCP packet is lost, the process proceeds to S203, otherwise, the process proceeds to S205.

5203. The TCP device retransmits the corresponding TCP packet to the peer device, and starts a TCP retransmission timer and/or a TCP retransmission counter.

S204: The TCP device reduces the congestion window value of the sending end when the count value of the TCP retransmission timer and/or the TCP retransmission counter exceeds a preset threshold.

If the response message of the received TCP packet is a TCP NACK message, if the corresponding TCP packet is considered to be lost, the data is retransmitted, and the TCP retransmission timer or the TCP retransmission counter is started. When the TCP retransmission timer expires or the TCP retransmission counter exceeds a preset threshold, the congestion window value is reduced.

5205. The TCP device increases a congestion window value of the sending end.

After receiving the TCP ACK message fed back by the RLC device, the TCP device performs sliding of the transmission window and increases the size of the congestion window. The specific processing is the same as that in the existing TCP protocol.

The response message of the TCP packet received by the TCP device is the TCP NACK information. The specific processing is shown in FIG. 5, including:

S30 sets the retransmission timeout (RTO) threshold of the TCP device RTO_threshold.

5302. Receiving the TCP NACK information of the data packet n, it can be determined that the data packet n is lost.

5303. Start the TCP retransmission timer to record the RT0 time RT0_n of the data packet n.

5304. Determine whether RT0_n is greater than the RTO threshold RTO_threshold. If yes, proceed to S305, retransmit the data packet n and reduce the congestion window. Otherwise, enter S306, retransmit the data packet n, and the congestion window remains unchanged.

The size of the RT0 threshold RTO_threshold can be set according to actual needs. In the input, it is usually necessary to set a relatively small RTO threshold because the delay time of the direct packet loss of the RLC layer is very short.

In addition, considering the flow control of the RLC device and the MACD scheduling mechanism, the initial value of the congestion window value can be set to be the same as the advertised window size, that is, the flow control function is completely handed over to the RLC layer and the underlying MAC layer. Of course, if the RLC device can accurately feed back the NACK information of any TCP packet, the mechanism for using the RT0 to perform packet loss judgment in the TCP device may not be used.

In this way, the TCP device can perform effective congestion control according to the response message fed back by the RLC device, accurately retransmit the lost TCP packet, and optimize the wireless TCP system.

Embodiment 3

FIG. 6 is a signaling diagram of a message processing method for feedback packet loss according to the embodiment. As shown in FIG. 6, the method includes:

The S40 RAN TCP device transmits a TCP packet to the RAN RLC device.

S402. The RAN RLC apparatus groups the TCP data packet to form an RLC data packet. After receiving the TCP data packet sent by the TCP device at the transmitting end, the RAN RLC device groups the TCP data packet to form at least one RLC data packet, and records the TCP data packet and the RLC data packet. Correspondence.

S403. The RAN RLC apparatus sends the RLC data packet to the user equipment UE.

5404. The UE RLC device feeds back the RLC ACK information to the RAN RLC device by receiving the RLC data packet.

S405. The UE RLC apparatus sends a TCP data packet formed by the RLC data packet group to the UE TCP device.

5406. The RAN RLC device constructs TCP ACK information according to the RLC ACK information fed back by the UE RLC device.

The RAN RLC device constructs ACK information of the corresponding TCP packet according to the relationship between the current RLC data packet and the TCP data packet, and then feeds back the TCP ACK information to the RAN TCP device.

5407. The RAN RLC device sends the TCP ACK information to the RAN TCP device. When the RAN TCP device receives the TCP ACK information, it is determined that the TCP packet has no packet loss.

S408: The RAN RLC device receives the TCP ACK information fed back by the UE TCP device.

5409. The RAN RLC device compares the TCP ACK information fed back by the UE TCP device with the TCP ACK information.

Generally, the RLC ACK information fed back by the UE RLC device is generally more than the TCP fed back by the UE TCP device.

The ACK message arrived early. If the TCP ACK information fed back by the UE TCP device is consistent with the constructed TCP ACK information, it is confirmed that there is no packet loss, and the TCP ACK information fed back by the UE TCP device is not sent to the RAN TCP device. If it is inconsistent, it is determined that the RLC data packet is lost when the UE RLC device sends the UE TCP device, and the packet loss may be determined according to the TCP ACK information and the RLC ACK information fed back by the peer device. And a TCP packet, and instructing the TCP device to retransmit the TCP packet in which the packet loss occurs or to send the RLC packet corresponding to the TCP packet in which the packet loss occurs, and perform a retransmission operation. At this time, there may be a problem in the flow control of the transmitting end, which causes the buffer of the UE TCP device to overflow, and the TCP packet that sends the RLC ACK information is discarded by the TCP device after being transmitted to the TCP device.

For example, the RAN RLC device sends 6 data packets to the UE, specifically identified as 1 to 6, and the RLC ACK information fed back by the UE RLC device is 1, 2, 3, 5, 6 , indicating that the received identifier is 1, 2, 3 The RLC data packet of 5, 6 corresponds to the correspondence between the RLC data packet identifier and the TCP data packet identifier, and the corresponding TCP ACK information can be constructed according to the RLC ACK, and the RLC data packet identifier corresponds to the TCP data packet identifier. For example, the constructed TCP ACK information is also 1, 2, 3, 5, and 6, indicating that the TCP packets with the identifiers 1, 2, 3, 5, and 6 have no packet loss. The TCP ACK information fed back by the UE TCP device is 3, indicating that the data packet with the identifier 1, 2, 3 is received. It can be seen that the TCP ACK information fed back by the UE TCP device is inconsistent with the constructed TCP ACK information, and it can be determined that the TCP packet with packet loss occurs, and can be determined according to the TCP ACK information and the constructed TCP ACK information fed back by the UE TCP device. If the TCP packet with packet loss is a TCP packet with the identifier 4, the RAN TCP device is instructed to retransmit the TCP packet with the identifier 4 or the RLC packet with the RAN RLC device retransmission identifier 4, corresponding to the identifier 4 TCP packet. For RLC packet identification and TCP packet identification is not - corresponding In the case of the corresponding relationship, the identifier of the lost RLC data packet and the corresponding TCP packet identifier are similarly determined, and the packet retransmission of the lost packet is performed.

S41: The UE RLC device feeds back the RLC NACK information to the RAN RLC device for the unreceived RLC data packet.

The S41 RAN RLC device retransmits the RLC packet that feeds back the RLC NACK information.

The RAN RLC device retransmits the corresponding RLC packet and starts the RLC retransmission timer or the RLC retransmission counter. When the count value of the RLC retransmission timer and/or the RLC retransmission counter exceeds a preset threshold, it indicates that an RLC random packet loss, an RLC timeout packet loss, an RLC retransmission timeout, or an RLC retransmission failure occurs. S41 2.

In an RLC device, there are many cases in which one data is lost. For example, if its cache cannot receive TCP packets from the PDCP layer, the RLC device can directly discard the RLC packets. Or, after an RLC packet is transmitted multiple times, exceeds the retransmission time limit, or exceeds the retransmission limit, the NACK is fed back to the TCP device. That is, the RAN RLC device considers various packet loss scenarios, but the feedback to the TCP layer is a NACK message, because for the RAN TCP device, a certain TCP packet is not successfully transmitted.

541 2. The RAN RLC device constructs TCP NACK information according to the RLC NACK information, and is used to instruct the TCP device to retransmit the TCP data packet corresponding to the TCP NACK information.

541 3. The RAN RLC device sends TCP NACK information to the RAN TCP device.

5414. The RAN TCP device determines a packet loss condition of the TCP packet.

The packet loss condition is determined according to the TCP ACK information or the TCP NACK information fed back by the RAN RLC device. When the TCP ACK message is received, it indicates that the packet transmission was successful.

When the TCP NACK information is received, the TCP device determines the packet loss as follows: First, when the RLC device feeds back the TCP NACK information, it indicates that packet loss must occur. Lost data packets may fail after multiple retransmissions, or they may be directly discarded by the RLC device. If the NACK information fed back after multiple failures is retransmitted, the RT0 recording time of the data packet is relatively long. If it is directly discarded by the RLC device, there are two possibilities: One is to wait for a period of time to discard, The data packet is recorded in the RT0 timer of the TCP device for a relatively long time; one is because the buffer is already full and directly discarded, then the time recorded by the RT0 timer of the TCP device is very short. Under normal circumstances, whether it is retransmission timeout, retransmission times, or waiting timeout, then the RT0 time of the packet is relatively long, and the time of the RT0 timer recorded by the packet is Very short.

S415. The RAN TCP device retransmits the lost TCP packet.

The specific transmission conditions of the RLC data packet are as follows: The first one is a successful transmission, the second is a retransmission multiple success, the third is a retransmission multiple times and the number of retransmissions fails, the fourth is After retransmission, it fails more than the time limit of retransmission. In the fifth case, if the buffer of the RLC device is full, the received data packet is directly discarded. In the third, fourth, and fifth cases, the RLC devices feed back the NACK information corresponding to the TCP packet to the TCP device, and the TCP layer retransmits.

In this embodiment, the TCP device and the RLC device are grouped on the radio side (ie, the RAN side), which can completely solve the problem of packet loss judgment in the wireless TCP, and also avoid the delay problem of information transmission.

The network element capable of providing the RLC device in the RAN side may be a device such as an RNC or an eNodeB, and the TCP ACK/NACK information fed back by the RAN side may provide a network element location as an RNC, an eNodeB, and a general packet radio service gateway support node (Gateway GPRS). Support Node, GGSN) and Packet Data Network Gateway (P-GW). That is to say, the TCP ACK/NACK information fed back by the RAN side can be directly fed back to other network elements through the RNC or the eNodeB, or can be forwarded to the GGSN, P-GW, etc. through the RNC or the eNodeB, and then forwarded to other network elements. Therefore, in this embodiment, the RLC device may be an RNC, an eNodeB, or the like, and the TCP device may be a RNC, an eNodeB, a GGSN, a P-GW, or the like.

Since the RNC to the GGSN and the eNodeB to the P-GW are both GPRS Tunneling Protocol (User Plane, GTP-U) protocols, the extension header of the GTP-U protocol can be used to transmit the corresponding TCP. ACK/NACK information. 7 is a schematic diagram of an extended header of a GTP-U protocol, including an extended header length, an extended header content, and a next extended header type, which can be transmitted as TCP ACK/NACK information. Of course, TCP ACK/NACK information is also available. The transmission is performed by using the ACK and NACK flag bits in the SACK in the RLC device. Since the SACK is located in the RLC device, it is not required to have the SACK option for the TCP device, and can be transmitted.

It should be noted that the foregoing RAN TCP device and the RAN RLC device may be in the same base station device, and the base station device may be a device such as an RNC or an eNodeB. Certainly, the TCP device at the transmitting end may not be in the RAN side, that is, there is no TCP optimization in the RAN side, and the RAN TCP device and the RAN RLC device are in different network elements, and the RAN RLC device may send the feedback TCP ACK information or The TCP NACK information is fed back to the TCP device of other network elements, for example, a Serving GPRS Suppering Node (SGSN) or a Policy and Charging Rules function (Po li cy And Charging Rul es Funcion, The specific processing of the network element, such as the PCRF, is similar to the embodiment, and will not be described again.

The above is a detailed description of the message processing method and the congestion control method for the feedback packet loss provided by the present invention. The message processing device and the congestion control device for feedback packet loss provided by the present invention are described in detail below.

Embodiment 4

FIG. 8 is a schematic diagram of a message processing apparatus for feedback packet loss according to the embodiment. As shown in FIG. 8, the apparatus of the present invention includes: a packet unit 501, a receiving unit 502, a processing unit 503, and a transmitting unit 504.

The packet unit 501 is configured to receive a TCP packet sent by the TCP device, group the TCP packet into an RLC packet, and send the RLC packet to the peer device.

The packet unit 501 specifically includes: a receiving subunit, a recording subunit, a packet subunit, and a storage subunit (not shown).

The receiving subunit is configured to receive the TCP data packet sent by the TCP device and obtain the information of the TCP data packet carried in the TCP data packet.

In the actual application scenario, the TCP packet sent by the TCP device at the transmitting end usually performs pre-processing such as header compression and packet parsing through other protocol layers before reaching the RLC device, and the receiving sub-unit receives the processed TCP. data pack. FIG. 3 is a schematic diagram of the correspondence between protocol layers in the RNC. As shown in FIG. 3, the TCP proxy performs data transmission with the base station NodeB through the RNC. The TCP proxy server includes multiple TCP connections for multiple users. The RNC may include a Packet Data Convergence Pro toco l (PDCP) layer, an RLC device, a dedicated media access control (Met ia Acces s Cont ro lD , MACD ) layer, and a media access control service ( Med Ia Acces s Cont ro l CI i ent ) layer. The RNC receives TCP packets sent from multiple TCP connections of the user through the PDCP layer, and the PDCP layer parses the TCP packets to obtain information of the TCP packets, and the header information includes one or any combination of the following: IP The address, port, and byte range are used to identify the TCP packet based on the information of the TCP packet. The PDCP layer also has a header compression function that passes the header-compressed TCP packets to the RLC device. The MACD layer performs scheduling on the RLC data packets sent by the RLC device, and the MACC layer is used to aggregate and send the services in the cell to the NodeB.

If the RLC device receives the TCP packet sent by the TCP device at the transmitting end, the receiving subunit further parses the TCP packet to obtain the information of the TCP packet, and then sends the parsed TCP packet to the PDCP layer for header. The compression process is performed, and the data packet processed by the PDCP layer is further provided to the recording subunit.

The recording subunit is configured to identify the TCP data packet according to the information of the TCP data packet obtained by the receiving subunit, and record an identifier of the TCP data packet.

Correspondingly, the identifier of the TCP packet recorded by the recording subunit includes one or any combination of the information of the following TCP packets: IP address, port and byte range.

The packet subunit is configured to perform RLC grouping on the TCP packet received by the receiving subunit to form an RLC data packet, and identify the RLC data packet.

The packet sub-unit determines the size of the packet according to the scheduling of the MACD layer, and how much data is sent to the MACD layer for traffic control to avoid congestion of the IuB port between the RNC and the NodeB.

The storage subunit is configured to establish and record a correspondence between the RLC data packet and the TCP data packet according to the identifier of the TCP data packet recorded by the recording subunit and the identifier of the RLC data packet obtained by the group packet subunit. The correspondence between the RLC data packet recorded by the storage subunit and the TCP data packet is one of the following three types: one of the TCP data packets corresponds to one of the RLC data packets; and one of the TCP data packets corresponds to multiple of the RLC data packets. Or, a plurality of the TCP data packets correspond to one of the RLC data packets.

The receiving unit 502 is configured to receive a response message of the RLC data packet returned by the RLC device sent by the RLC device of the peer device to the RLC data packet.

The RLC device of the peer device returns the response information of the corresponding RLC packet for each RLC packet. The response information of the RLC data packet received by the receiving unit 502 includes RLC ACK information and/or RLC NACK information.

The processing unit 503 is configured to construct a response message of the TCP packet corresponding to the RLC data packet according to the response message of the RLC data packet received by the receiving unit 502.

The processing unit 503 constructs a response message of the TCP packet based on the correspondence between the RLC packet recorded in the packet unit 501 and the TCP packet.

If the response message of an RLC packet is ACK, the response message of the TCP packet corresponding to the RLC packet is ACK. If the response message of an RLC packet is NACK, the response message of the TCP packet corresponding to the RLC packet is NACK. Using this correspondence, the processing unit 503 constructs a response message of the TCP packet according to the response message of the RLC packet, that is, constructs TCP ACK information by using the RLC ACK information, and constructs TCP NACK information by using the RLC NACK information to indicate the TCP device. Retransmitting the TCP packet corresponding to the TCP NACK information.

The processing unit 503 constructs a response message of the TCP data packet according to the response message of the RLC data packet by using the correspondence between the RLC data packet and the TCP data packet recorded by the storage subunit. Specifically, if a TCP packet corresponds to only one RLC packet, the ACK of the RLC packet is an ACK of the TCP packet. If a TCP packet corresponds to multiple RLC packets, if the ACK of multiple RLC packets is received, then the TCP packet can be considered as ACK, that is, multiple RLC packets are required to be ACK. If multiple TCP packets correspond to one RLC packet, the ACK of the RLC packet is the ACK of multiple TCP packets.

The sending unit 504 is configured to feed back a response message of the TCP packet obtained by the processing unit 503 to TCP device.

The TCP device determines whether the TCP packet is lost according to a response message of the TCP packet. When the transmitting unit 504 transmits the TCP NACK information, the TCP device at the transmitting end determines that the TCP packet has been dropped. When the TCP device at the transmitting end receives an ACK of a certain TCP packet, it is determined that no packet loss has occurred in the TCP packet.

The response message of the TCP packet fed back by the sending unit is transmitted through an extension header of the GPRS tunneling protocol GTP-U of the user plane or a selective acknowledge SACK.

Optionally, the message processing apparatus of the present invention further includes: a comparing unit 505 and a first retransmission unit

506.

The comparing unit 505 is connected to the receiving unit 502, the processing unit 503, and the transmitting unit 504. The receiving unit 502 is further configured to receive ACK information fed back by the TCP device of the peer device. The comparing unit 505 is configured to compare the ACK information fed back by the TCP device received by the receiving unit 502 with the TCP ACK information obtained by the processing unit 503, and if not, determine that the data packet is sent to the receiving end. If the TCP device is the same, it is determined that no packet loss occurs, and the sending unit 504 is no longer triggered to send the ACK information fed back by the TCP device to the transmitting end.

Generally, the RLC ACK information fed back by the UE RLC device is generally earlier than the TCP ACK information fed back by the UE TCP device. If the TCP ACK information fed back by the UE TCP device is consistent with the constructed TCP ACK information, the comparing unit 505 confirms that there is no packet loss, and does not send the TCP ACK information fed back by the TCP device to the TCP device of the transmitting end. If not, the comparing unit 505 determines that the RLC data packet is lost when the RLC device of the UE sends the TCP device to the UE, and may use the TCP ACK information and the RLC ACK information that are fed back by the peer device. Determining the TCP packet in which the packet loss occurs, and instructing the TCP device to retransmit the TCP packet in which the packet loss occurs or to send the RLC packet corresponding to the TCP packet in which the packet loss occurs, and perform a retransmission operation. At this time, there may be a problem in the flow control of the transmitting end, which causes the buffer of the UE TCP device to overflow. The TCP packet that sends the RLC ACK information is discarded by the TCP device after being transmitted to the TCP device. The first retransmission unit 506 is connected to the receiving unit 502 and the processing unit 503. The first retransmission unit 506 is configured to: when the response message of the RLC data packet received by the receiving unit 502 is RLC NACK information, retransmit the RLC data packet of the RLC data packet to the RLC NACK information. a peer device, and starting an RLC retransmission timer and/or an RLC retransmission counter; when the count value of the RLC retransmission timer and/or the RLC retransmission counter exceeds a preset threshold, the trigger processing unit 503 is configured according to the The RLC NACK information constructs TCP NACK information.

Embodiment 5

FIG. 9 is a schematic diagram of a message processing apparatus for feedback packet loss according to an embodiment of the present invention. As shown in FIG. 9, the apparatus includes: a receiving unit 601, a determining unit 602, a second retransmission unit 603, and an adjusting unit 604.

The receiving unit 601 is configured to receive TCP NACK information sent by the RLC device.

The TCP NACK information is obtained by the apparatus of the fourth embodiment.

The determining unit 602 is configured to determine the TCP packet of the packet loss according to the TCP NACK information received by the receiving unit 601.

The second retransmission unit 603 is configured to: after the determining unit 602 determines the TCP packet of the lost packet, retransmit the TCP packet of the lost packet to the UE, and start a TCP retransmission timer and/or a TCP retransmission counter. .

The adjusting unit 604 is configured to reduce the congestion window value of the transmitting end when the count value of the TCP retransmission timer and/or the TCP retransmission counter started by the second retransmission unit 603 exceeds a preset threshold.

If the receiving unit 601 receives the response message of the TCP packet as a TCP NACK message, the determining unit 602 determines that the corresponding TCP packet is lost, the second retransmission unit 603 performs data retransmission, and starts the TCP retransmission timer. Or TCP retransmission counter. When the TCP retransmission timer expires or the TCP retransmission counter exceeds a preset threshold, the adjustment unit 604 reduces the congestion window value. After the receiving unit 601 receives the TCP ACK message fed back by the RLC device, the determining unit 602 determines that the data packet has no packet loss, and the adjusting unit 604 performs sliding of the sending window, and increases the size of the congestion window, and the specific processing process and existing The processing in the TCP protocol is the same. Embodiment 6

FIG. 10 is a schematic structural diagram of an RLC device according to an embodiment of the present invention. As shown in FIG. 10, the RLC device of the embodiment of the present invention may include:

The processor 701, the first interface 702, and the second interface 703.

The processor 701 may be a single core or multi-core central processing unit (Centra l Proces s ing Uni t ,

The CPU) is either a specific integrated circuit (ASIC) or one or more integrated circuits configured to implement embodiments of the present invention.

The first interface 702 is for interacting with a TCP device.

The second interface 703 is used to interact with the peer device.

The processor 701 is used to:

Receiving, by the first interface, a TCP data packet sent by the TCP device;

Grouping the TCP data packet into an RLC data packet;

Sending, by the second interface, the RLC data packet to the peer device;

Sending a response message of the TCP packet to the TCP device through the first interface. Specifically, the TCP packet received by the first interface 702 carries information of the TCP packet. In the actual application scenario, the TCP packet received by the first interface 702 may be a processed TCP packet, or may be a TCP packet sent by a TCP device.

The processor 701 identifies the TCP data packet according to the information of the TCP data packet, and records an identifier of the TCP data packet; performing an RLC group packet on the TCP data packet to form an RLC data packet, and identifying the An RLC data packet; and, according to the identifier of the TCP data packet and the identifier of the RLC data packet, establishing and recording a correspondence between the RLC data packet and the TCP data packet.

The processor 701 uses the RLC data packet and the TCP according to the response message of the RLC data packet. Corresponding relationship of the data packet, constructing a response message of the TCP data packet.

If the response message of the RLC packet is an RLC acknowledgement ACK message, the processor 701 constructs TCP ACK information of the TCP packet based on the RLC ACK information.

The second interface 703 may further receive the TCP ACK information that is fed back by the peer device, and the processor 701 compares the TCP ACK information fed back by the peer device with the constructed TCP ACK information, and if yes, determine If no packet loss occurs, the TCP ACK information fed back by the peer device is not sent to the TCP device; if not, it is determined that the TCP packet is generated when the TCP device is sent to the peer device. Lose the package. When it is determined that the packet loss occurs, the processor 701 determines, according to the TCP ACK information and the RLC ACK information fed back by the peer device, the TCP packet in which the packet loss occurs, and instructs the TCP device to retransmit the TCP packet that is lost. The data packet or the RLC data packet corresponding to the TCP packet in which the packet loss occurs is sent through the second interface 703.

If the response message of the RLC data packet is the RLC negative acknowledgement NACK information, the processor 701 is configured to construct TCP NACK information of the TCP data packet according to the RLC NACK information, to instruct the TCP device to retransmit the TCP NACK. The TCP packet corresponding to the information.

The processor 701 retransmits the RLC data packet of the RLC data packet to the peer device, and starts an RLC retransmission timer and/or an RLC retransmission counter; when the RLC retransmits When the count value of the timer and/or the RLC retransmission counter exceeds a preset threshold, the TCP NACK information is constructed according to the RLC NACK information.

Specifically, the RLC device may also perform the processing methods shown in FIG. 1-3 and FIG. 6 above, and details are not described herein.

Example 7

FIG. 11 is a schematic structural diagram of a TCP device according to an embodiment of the present invention. As shown in FIG. 11, the TCP device in the embodiment of the present invention may include: a processor 801 and a communication interface 802.

The processor 801 may be a single core or multi-core central processing unit (CPU), or an application specific integrated circuit (ASIC), or one or more integrated systems configured to implement the embodiments of the present invention. Circuit. Communication interface 802 is used to interact with the RLC device.

The processor 801 is used to:

Receiving, by the communication interface, TCP NACK information sent by the RLC device;

The TCP NACK information is configured by the RLC device according to the RLC NACK information. The specific configuration method is as described in the first embodiment or the third embodiment, and details are not described herein.

When determining that there is a packet loss TCP packet, the processor 801 is further configured to retransmit the lost packet TCP packet to the peer device through the communication interface 802, and start a TCP retransmission timer and/or TCP. Retransmission counter; when the count value of the TCP retransmission timer and/or the TCP retransmission counter exceeds a preset threshold, the congestion window value of the transmitting end is reduced, thereby performing congestion control on the transmission process.

Specifically, the TCP device further performs the foregoing control method shown in FIG. 4-6 according to the instruction, and details are not described herein again.

It should be noted that the RLC device in Embodiment 6 may be a radio network controller RNC or an evolved base station eNodeB. The TCP device in the seventh embodiment may be an RNC or an eNodeB, or may be a device such as a GGSN or a P-GW. Since the RNC to the GGSN, the eNodeB and the P-GW are both the GPRS Tunneling Protocol (GPRS Tuning Protocol to Protocol), the response message of the TCP packet It is transmitted through the extension header of the user plane's GPRS tunneling protocol GTP-U. Of course, the response message of the TCP packet can also be transmitted by using the ACK and NACK flag bits in the SACK in the RLC device.

The foregoing TCP device and the RLC device may be in the same base station device, and the base station device may be a device such as an RNC or an eNodeB. If the TCP device and the RLC device are in different network elements, the RLC device may feed back the TCP ACK information or the TCP NACK information to the TCP device of the other network element. The specific processing is similar to the embodiment, and details are not described herein.

The message processing method and device for feedback packet loss provided by the present invention determine whether a current TCP packet is correctly received through the ACK/NACK information fed back by the RLC layer, thereby accurately determining the TCP packet loss and obtaining accurate TCP packet loss information. , only need to retransmit the data that was not received correctly, It can reduce unnecessary retransmissions, improve the performance of wireless TCP, and make full use of air interface resources.

A person skilled in the art should further appreciate that the elements and algorithm steps of the various examples described in connection with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both, in order to clearly illustrate hardware and software. Interchangeability, the composition and steps of the various examples have been generally described in terms of function in the above description. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the solution. A person skilled in the art can use different methods for implementing the described functions for each particular application, but such implementation should not be considered to be beyond the scope of the present invention.

The steps of a method or algorithm described in connection with the embodiments disclosed herein can be implemented in hardware, a software module executed by a processor, or a combination of both. Software modules can be placed in random access memory (RAM), memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disk, removable disk, CD-ROM, or technical field Any other form of storage medium known.

The above described embodiments of the present invention are further described in detail, and the embodiments of the present invention are intended to be illustrative only. The scope of the protection, any modifications, equivalents, improvements, etc., made within the spirit and scope of the invention are intended to be included within the scope of the invention.

Claims

claims

1. A wireless link control RLC device, characterized in that the device includes: a processor, a first interface and a second interface;

The first interface is used to interact with the transmission control protocol TCP device;

The second interface is used to interact with the peer device;

The processor is used for:

Receive the TCP data packet sent by the TCP device through the first interface;

Group the TCP data packets into RLC data packets;

Send the RLC data packet to the peer device through the second interface;

Receive the response message of the RLC data packet returned by the peer device through the second interface;

Construct the response message of the TCP data packet corresponding to the RLC data packet according to the response message of the RLC data packet;

The response message of the TCP data packet is fed back to the TCP device through the first interface.

2. The device according to claim 1, characterized in that, the TCP data packet received by the first interface carries information of the TCP data packet, and the information of the TCP data packet includes one or any of the following: Combined: IP address, port and byte range;

The processor is used to package the TCP data packets into RLC data packets, which specifically includes: The processor is used to:

Identify the TCP data packet according to the information of the TCP data packet, and record the identification of the TCP data packet;

Perform RLC grouping of the TCP data packets to form RLC data packets, and identify the RLC data packets; and

According to the identification of the TCP data packet and the identification of the RLC data packet, establish and record the

Correspondence between RLC data packets and TCP data packets.

3. The device according to claim 2, wherein the processor is configured to perform the The response message of the RLC data packet constructs the response message of the TCP data packet corresponding to the RLC data packet, including:

The processor is used for:

According to the response message of the RLC data packet, the corresponding relationship between the RLC data packet and the TCP data packet is used to construct the response message of the TCP data packet.

4. The device according to claim 1, wherein the response message of the RLC data packet is RLC confirmation ACK information, and the processor is configured to construct the RLC data packet corresponding to the response message of the RLC data packet. The response message of the TCP data packet, specifically includes:

The processor is configured to construct TCP ACK information of the TCP data packet according to the RLC ACK information.

5. The device according to claim 4, wherein the processor is further configured to: receive TCP ACK information fed back by the peer device through the second interface;

The TCP ACK information fed back by the peer device is compared with the constructed TCP ACK information. If they are inconsistent, it is determined that the TCP data packet is lost when sent to the TCP device of the peer device.

6. The device according to claim 5, characterized in that when packet loss occurs, the processor is also used to:

Determine the TCP data packet in which packet loss occurs based on the TCP ACK information and RLC ACK information fed back by the peer device;

Instruct the TCP device to retransmit the TCP data packet in which packet loss occurs or to send the RLC data packet corresponding to the TCP data packet in which packet loss occurs through the second interface.

7. The device according to claim 4, wherein the processor is further configured to: receive TCP ACK information fed back by the peer device through the second interface;

Compare the TCP ACK information fed back by the peer device with the constructed TCP ACK information. If they are consistent, it is determined that no packet loss has occurred, and the TCP fed back by the peer device is no longer sent to the TCP device. ACK information.

8. The device according to claim 1, characterized in that: the response message of the RLC data packet The information is RLC negative acknowledgment NACK information, and the processor is configured to construct a response message of the TCP data packet corresponding to the RLC data packet according to the response message of the RLC data packet, specifically including:

The processor is configured to construct TCP NACK information of the TCP data packet according to the RLC NACK information, so as to instruct the TCP device to retransmit the TCP data packet corresponding to the TCP NACK information.

9. The device according to claim 8, characterized in that the processor is configured to perform the

RLC NACK information structure TCP NACK information of TCP data packet, specifically including:

The processor is used for:

Retransmit the RLC data packet whose response message is RLC NACK information to the peer device, and start the RLC retransmission timer and/or RLC retransmission counter;

When the count value of the RLC retransmission timer and/or the RLC retransmission counter exceeds the preset threshold, TCP NACK information is constructed based on the RLC NACK information.

10. The device according to claim 1, characterized in that the response message of the TCP data packet is delivered through the extension header of the GPRS Tunneling Protocol GTP-U on the user plane or the TCP Selective Acknowledgment SACK option.

11. The device according to claim 1, characterized in that the RLC device is a radio network controller RNC or an evolved base station eNodeB.

12. A TCP device, characterized in that the device includes: a processor and a communication interface; the communication interface is used to interact with the RLC device;

The processor is used for:

Receive TCP NACK information sent by the RLC device through the communication interface, and the TCP NACK information is constructed by the RLC device based on the RLC NACK information;

Determine the lost TCP data packet based on the TCP NACK information.

13. The device according to claim 12, characterized in that, after determining packet loss, the processor is also used to:

Retransmit the lost TCP data packet to the peer device through the communication interface, and start

TCP retransmission timer and/or TCP retransmission counter; When the count value of the TCP retransmission timer and/or the TCP retransmission counter exceeds the preset threshold, the congestion window value of the sending end is reduced.

14. The device according to claim 12, characterized in that the TCP device is an RNC, eNodeB, GGSN, SGSN or PGW.

15. A base station equipment, characterized by including:

The RLC device as described in any one of claims 1 to 10 and the TCP device as described in any one of claims 12 to 13.

16. A message processing method for feedback packet loss, characterized in that the method includes:

The RLC device receives the TCP data packet sent by the TCP device, packages the TCP data packet to form an RLC data packet, and sends the RLC data packet to the peer device;

The RLC device receives the response message of the RLC data packet returned by the peer device; the RLC device constructs a response message of the TCP data packet corresponding to the RLC data packet according to the response message of the RLC data packet;

The RLC device feeds back the response message of the TCP data packet to the TCP device.

17. The message processing method according to claim 16, characterized in that, the TCP data packet received by the RLC device carries information of the TCP data packet, and the information of the TCP data packet includes one of the following: One or any combination of: IP address, port and byte range;

Packaging the TCP data packets into RLC data packets includes:

The RLC device identifies the TCP data packet according to the information of the TCP data packet, and records the identification of the TCP data packet;

The RLC device performs RLC grouping on the TCP data packet to form an RLC data packet, and identifies the RLC data packet;

The RLC device establishes and records the corresponding relationship between the RLC data packet and the TCP data packet according to the identification of the TCP data packet and the identification of the RLC data packet.

18. The message processing method according to claim 17, characterized in that, according to the

The response message of the RLC data packet constructs the response message of the TCP data packet, specifically: According to the response message of the RLC data packet, the corresponding relationship between the RLC data packet and the TCP data packet is used to construct the response message of the TCP data packet.

19. The message processing method according to claim 16, characterized in that the response message of the RLC data packet is RLC ACK information;

The response message of the TCP data packet is constructed according to the response message of the RLC data packet, specifically as follows:

Construct TCP ACK information of the TCP data packet based on the RLC ACK information.

20. The message processing method according to claim 19, characterized in that, after the RLC device feeds back the response message of the TCP data packet to the TCP device, it further includes:

The RLC device receives the TCP ACK information fed back by the peer device;

The RLC device compares the TCP ACK information fed back by the peer device with the constructed TCP ACK information. If they are inconsistent, it is determined that the data packet is lost when sent to the TCP device of the peer device. Bag.

21. The message processing method according to claim 20, characterized in that when packet loss occurs, the method further includes:

The RLC device determines the TCP data packet in which packet loss occurs based on the TCP ACK information and RLC ACK information fed back by the peer device;

The RLC device instructs the TCP device to retransmit the TCP data packet in which packet loss occurs or to send the RLC data packet corresponding to the TCP data packet in which packet loss occurs.

22. The message processing method according to claim 19, characterized in that, after the RLC device feeds back the response message of the TCP data packet to the TCP device, it further includes:

The RLC device receives the TCP ACK information fed back by the peer device;

The RLC device compares the TCP ACK information fed back by the peer device with the constructed TCP ACK information. If they are consistent, it determines that packet loss has not occurred, and no longer sends the peer device to the TCP device. TCP ACK information fed back by the device.

23. The message processing method according to claim 16, characterized in that: the RLC data The response message of the packet is RLC NACK information;

The TCP NACK information of the TCP data packet is constructed according to the RLC NACK information to instruct the TCP device to retransmit the TCP data packet corresponding to the TCP NACK information.

24. The message processing method according to claim 23, wherein the TCP NACK information of the TCP data packet is constructed according to the RLC NACK information, specifically including:

25. The message processing method according to claim 16, characterized in that the response message of the TCP data packet is transmitted through the extension header of GTP-U or the TCP SACK option.

26. A message processing method for feedback packet loss, characterized in that the method includes: receiving TCP negative acknowledgment NACK information sent by the RLC device, the TCP NACK information being constructed by the RLC device based on the RLC NACK information;

Determine the lost TCP data packet based on the TCP NACK information.

27. The message processing method according to claim 26, characterized in that, after determining the lost TCP data packet based on the TCP NACK information, it further includes:

Retransmit the lost TCP data packet to the peer device, and start the TCP retransmission timer and/or TCP retransmission counter;

When the count value of the TCP retransmission timer and/or the TCP retransmission counter exceeds the preset threshold, the congestion window value of the sending end is reduced.