CN102118356A - Message transmission method and transmission device - Google Patents

Abstract

The invention discloses a message transmission method and a message transmission device. The method comprises that: a transmitter encapsulates a plurality of received messages with the same destination address according to a generic route encapsulation (GRE) protocol respectively; the encapsulated messages are set in a unified way behind a public information field to form a multiplexed encapsulated message; and the transmitter transmits the multiplexed encapsulated message to a receiver. The embodiment of the invention reduces the average encapsulation overhead of each GRE message by multiplexing the public information field, and in addition, further performs compression transmission on GRE headers, thereby improving the transmission efficiency.

Description

A message sending method and sending device

technical field

The embodiments of the present invention relate to the technical field of communications, and in particular, to a method and device for sending a message.

Background technique

Generic Route Encapsulation GRE (Generic Route Encapsulation) is a layer-3 tunneling protocol. This type of protocol specifies how to use one network protocol to encapsulate another network protocol. This tunnel encapsulation method has been used by many Network adoption. For example, the R3/R4/R6 interface of the WiMAX network can adopt this encapsulation method. A WiMAX network is mainly composed of three parts, namely a terminal (MS), an access service network (ASN), and a connection service network (CSN). The access service network includes a base station (BS) and an access service network gateway (ASN) -GW). Wherein, the communication interface between the BS and the ASN-GW is called the R6 interface, the communication interface between the ASN-GW and the CSN is called the R3 interface, and the communication interface between the ASN and the ASN is called the R4 interface.

As shown in Figure 1, in a WiMAX network, encapsulation using the GRE protocol is optional on the R3 interface, and mandatory on the R4 and R6 interfaces. The structure of the GRE header is shown in Figure 2. The structure contains 4 fields:

1) Control field: the S bit of the control field is used to identify whether the Sequence Number is carried;

2) Protocol type field Protocol Type: The protocol type indicated in the protocol type field can be

Any of IPv4, IPv6, Ethernet, WiMAX Payload;

3) KEY: used to identify the Data Path ID;

4) Sequence Number: The sequence number of the transmission payload, when the transmitted data carries this

The value of the control field MUST be 1 for the serial number.

The entire GRE message includes the GRE message header used to indicate the relevant information of the encapsulated payload and the encapsulated object GRE payload. The maximum length of the GRE header is 12 bytes. For each interface using the GRE protocol, the Any type of packets, such as IPv4 packets, IPv6 packets, and Ethernet packets, will be transmitted as the payload of the GRE packet.

Taking the IP-CS of the IP convergence sublayer of the R6 interface as an example, its transmission protocol model is shown in Figure 3. Each IP message (including the message sent from the CSN to the ASN-GW and the message sent from the MS to the ASN-GW message) will be encapsulated as the payload of the GRE message, and then IP, MAC and PHY encapsulation is performed on the GRE message and transmitted. The IP encapsulation here is the outer layer IP encapsulation, and its IP address information addresses the destination addresses of the ASN-GW and the BS.

Still taking the IP-CS on the R6 interface as an example, for a message with a relatively small length transmitted through the R6 interface, such as a VoIP voice frame, which is usually about 100 bytes, encapsulation on the R6 interface before transmission will cause a large overhead (each protocol The actual size of the overhead of the layer encapsulation header can refer to Figure 4, excluding the 20-byte PHY overhead of the physical layer, the encapsulation overhead of each packet is 50 bytes), and the transmission efficiency is very low (here the transmission efficiency is defined as: payload length /(payload length + encapsulation overhead)). However, the actual network usually contains a large number of such messages below 200 bytes. For example, in the Internet network, the proportion of such messages is about 40% to 60%. Transmission will cause the average transmission efficiency of the entire network to be very low. The 20-byte IP header in Figure 4 is the basic size of the IPv4 header. After the IPv6 protocol is adopted, this part of the overhead will be larger. At this time, the size of the IPv6 header is at least 40 bytes, which will make the transmission efficiency lower.

Contents of the invention

The technical problem to be solved by the embodiments of the present invention is to provide a message sending method and device, which solves the problem of low message transmission efficiency in the prior art.

In order to solve the above technical problems, an embodiment of the present invention provides a message sending method, including:

The sender encapsulates the received multiple messages with the same destination address according to the general routing encapsulation GRE protocol;

Setting the plurality of encapsulated messages behind the public information field to form a multiplexed encapsulated message;

The sending end sends the multiplexed and encapsulated message to the receiving end.

The embodiment of the present invention also provides a sending device, including:

An encapsulation unit, configured to encapsulate the received multiple messages with the same destination address according to the general routing encapsulation GRE protocol;

A setting unit, configured to set the plurality of encapsulated messages after the public information field to form a multiplexed encapsulated message;

The sending unit is configured to send the multiplexed and encapsulated message to the receiving end.

The embodiment of the present invention reduces the average encapsulation overhead of each GRE message by multiplexing part of the common information fields, and further improves the transmission efficiency by further compressing and transmitting the GRE header.

Description of drawings

FIG. 1 is a prior art WiMAX network reference model;

FIG. 2 is a schematic diagram of a header structure encapsulated according to the GRE protocol in the prior art;

Fig. 3 is prior art WiMAX IP-CS protocol transmission model;

Fig. 4 is a schematic diagram of the actual overhead of packet packaging at the R6 port in the prior art;

Fig. 5 is a schematic diagram of the data transmission process of the R6 port of the embodiment of the present invention;

FIG. 6 is a schematic flow diagram of multiplexing transmission in a negotiation mode according to an embodiment of the present invention;

Fig. 7 is a message structure diagram for multiplexing transmission in a negotiation mode according to an embodiment of the present invention;

Fig. 8 is a message structure diagram of multiplexing indication using corresponding bits in the IP header according to an embodiment of the present invention;

FIG. 9 is a message structure diagram for multiplexing indication using additionally defined special fields in an embodiment of the present invention;

Fig. 10 is a message structure diagram of multiplexing indication using the GRE header of the multiplexing function according to an embodiment of the present invention;

Fig. 11 is a schematic flow chart of compression negotiation according to an embodiment of the present invention.

Detailed ways

In order to make the object, technical solution and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with the accompanying drawings.

Taking the R6 interface as an example, in the existing implementation mode, each packet arriving at the R6 interface must be encapsulated according to the GRE protocol, and the transmission overhead is very large. In order to reduce the transmission overhead, the method adopted in the embodiment of the present invention is shown in Figure 5. The data transmission process with the ASN-GW as the sending end and the BS as the receiving end is as follows:

The ASN-GW receives the message sent by the CSN;

The ASN-GW encapsulates the received multiple packets with the same destination address (for example: the destination address of the packets is the same BS) according to the GRE protocol, and then sets the multiple encapsulated packets in the public information After the field forms a multiplexing package message;

The ASN-GW sends the multiplexed encapsulated packet to the destination address.

The data transmission process with BS as the sending end and ASN-GW as the receiving end is as follows:

The BS receives the message sent by the MS;

The BS encapsulates multiple received messages with the same destination address (for example: the same ASN-GW) according to the GRE protocol, and then sets the multiple encapsulated messages after the public information field to form a multiplex encapsulated message;

The BS sends the multiplexed encapsulated message to the destination address.

The common information fields include IP, MAC and PHY.

Before sending the multiplexed encapsulated message or when sending the multiplexed encapsulated message, the entity corresponding to the destination address can be notified that the message sent to the destination address is a multiplexed encapsulated message, which can be implemented in the following two ways 1) Confirming that the message to be sent is a multiplexed encapsulated message by means of negotiation; 2) setting a field in the multiplexed encapsulated message to indicate that the message is a multiplexed encapsulated message.

On the basis of the above multiplexing, the GRE header can also be compressed to further reduce the transmission overhead.

The above scheme is described in detail below through several specific embodiments:

Embodiment one:

Fig. 6 is a schematic diagram of the process of multiplexed transmission using the negotiation method, which uses the method of function negotiation to perform multiplexed transmission of messages, and starts to use a fixed multiplexed message structure for transmission after negotiation. At this time, the receiver needs to judge how to parse the received message according to the negotiation status. A brief description of the negotiation process is as follows (the negotiation process may be initiated by either party):

The multiplexing function request message is initiated by the sender ASN-GW (or BS);

After receiving the multiplexing function request message, the receiver BS (or ASN-GW) replies with a confirmation message whether to enable the multiplexing function;

If the message replied by the receiver is an affirmative message, the sender starts to send the message with the multiplexed structure; the receiver parses the message according to the multiplexed structure;

If the message replied by the receiver is a negative message, or there is no reply, the sender encapsulates the message in a non-multiplexed structure, and the receiver parses the message in a non-multiplexed structure.

Wherein, the structure of above-mentioned message multiplexing is as shown in Figure 7, MH (Multiplex Header) in the figure is multiplexing subheader, and the field that it contains is used to indicate the position of each GRE message in the whole message and each GRE message Length information of the GRE packet. The multiplexed public information in the figure is PHY, MAC, and IP. Although they belong to different protocol header information, they are the same for the multiplexed packets and belong to public information.

Embodiment two

A special information field is used to indicate whether the transmission message is a multiplexed message. At this time, the receiving end only needs to obtain information on how to parse the multiplexed message according to the indication of the special information field. The multiplexing methods adopted in this embodiment include but are not limited to the following methods:

1) A certain bit in the IP header (such as a reserved bit) is used to indicate the type of the transmission message.

As shown in Figure 8, the MH (Multiplex Header) in the figure is a multiplexing sub-header, and the fields it contains are used to indicate the position of each GRE message in the entire message and the length information of each GRE message.

In this mode, the receiver first needs to judge whether the type of the transmission message indicated by the bit in the IP header is a multiplexed message, and if it is a multiplexed message, it will analyze it according to the first message structure. The first message structure includes MH and multiple GRE messages; if it is indicated as a non-multiplexed message, it is parsed according to the second message structure, and the second message structure contains a GRE packets.

2) An additionally defined special field is used to indicate whether the packet is a multiplexed packet. The multiplexed message structure is as shown in Figure 9, wherein, the special field is the Flag field in the figure, and MH (MultiplexHeader) in the figure is a multiplexing sub-header, and the fields it contains are used to indicate that each GRE message is in the The position in the entire message and the length information of each GRE message.

In this mode, it is first necessary to make an agreement through the agreement, so that both the sender and the receiver know that the Flag field is fixed in the transmitted message, and the receiver judges the value indicated in the Flag field after reading the IP header. Whether the type of the transmission message is a multiplexing message, if it is a multiplexing message (such as: Flag=1), then analyze according to the first message structure, the first message structure includes MH and A plurality of GRE messages; if the indication is a non-multiplexed message (for example: Flag=0), it is parsed according to the second message structure, and the second message structure contains one GRE message.

3) Define a GRE header with a multiplexing function. The new GRE header will add fields on the basis of the existing GRE header. The newly added fields include a multiplexing information control bit, which is used to indicate whether the message is multiplexed. message; the GRE header also needs to include the multiplexing subheader MH information (including segment control information and segment length information), which is used to indicate the position of each GRE message in the entire message and each GRE message The length information of the packet, and the multiplexing structure at this time are shown in FIG. 10 . In this way, it needs to be agreed through the agreement, so that both the sender and the receiver know that GRE is a header structure with a multiplexing function. After receiving the message, the receiver can determine how to parse the received message according to the newly added field. message.

The public information multiplexed in Embodiment 1 and Embodiment 2 above is IP, MAC and PHY, and these protocol header information are the same for the multiplexed messages, and belong to public information. There are certain multiplexing conditions for multiplexing the above-mentioned packets of the same IP, MAC, and PHY. First, they must have the same destination address. Second, possible multiplexing conditions include but are not limited to having the same service type or having the same DSCP value. These reusable packages can be from different users or from the same user.

The total size of multiplexed packets should have an upper limit, which can be set by the value of MTU (Maximum Transmission Unit) (to prevent multiplexed packets from being fragmented again), or determined according to other factors, but at least it should be less than or equal to MTU value.

Since the IP packet will be fragmented after exceeding the value of the MTU, each fragment is transmitted separately. The message multiplexed by the above multiplexing method does not include the fragmented message, that is, the fragmented message no longer participates in the multiplexing transmission process, and the fragmentation information is indicated in the relevant field in the IP header.

It is necessary to limit the arrival time before and after the multiplexed packets (limit the delay of the first arriving packet residing in the cache), so as to prevent the multiplexing processing from having a large impact on the data forwarding delay of the service plane. After the time limit is exceeded, the multiplexed packets must be sent immediately regardless of their current size.

Embodiment Three

Before the sender multiplexes and encapsulates the public information fields of the received GRE packets with the same destination address, the sender can also compress the information in the GRE header. In the next transmission process, the compressed information will not transmission, thereby saving transmission bandwidth.

The specific compression field can be determined according to the actual situation of the network. For example, the existing control bits usually do not change during transmission and can be compressed; the protocol type can be compressed in a network using a single application type, and so on. The specific compressed fields can be notified to the receiver through message negotiation, which mainly includes the following steps:

1. The sender sends a complete message to the receiver;

2. The sender sends a compressed transmission request/negotiation message to the receiver;

3. The receiving end saves the compressed field and sends a compressed transmission confirmation message to the sending end;

4. The sender saves the compressed field and sends the compressed multiplexed message;

5. The receiving end performs demultiplexing after receiving, and restores the compressed field, that is, refills the compressed message.

By multiplexing the transmission of the GRE message and compressing the GRE header, the average transmission overhead of each GRE payload is reduced, and the overall transmission efficiency is improved.

In addition, an embodiment of the present invention also provides a sending device, including:

An encapsulation unit, configured to encapsulate the received multiple messages with the same destination address according to the general routing encapsulation GRE protocol;

A setting unit, configured to set the plurality of encapsulated messages after the public information field to form a multiplexed encapsulated message;

The sending unit is configured to send the multiplexed and encapsulated message to the receiving end.

The sending device also includes:

The compression unit is used for the sending end to compress part of the information in the GRE header before encapsulating multiple received messages with the same destination address according to the GRE protocol.

Through the description of the above embodiments, those skilled in the art can clearly understand that the present invention can be realized by means of software plus a necessary general-purpose hardware platform, and of course it can also be realized by hardware. The above embodiments are only used to illustrate the present invention. The technical scheme of the invention is not limited thereto; although the present invention has been described in detail with reference to the aforementioned embodiments, those of ordinary skill in the art should understand that: it can still modify the technical solutions described in the aforementioned embodiments, or Some of the technical features are equivalently replaced; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims (11)

1. a file transmitting method is characterized in that, comprising:

Transmitting terminal encapsulates according to generic route encapsulation (GRE) agreement respectively a plurality of messages with identical destination address that receive;

Message after described a plurality of encapsulation is arranged on the public information field forms a multiplexing encapsulated message afterwards;

Transmitting terminal sends described multiplexing encapsulated message to receiving terminal.

2. method according to claim 1 is characterized in that,, also comprised before receiving terminal sends described multiplexing encapsulated message at described transmitting terminal: transmitting terminal and receiving terminal are held consultation, and determines that the message that will send is multiplexing encapsulated message.

3. method according to claim 2 is characterized in that, described multiplexing encapsulated message comprises:

Public information field, an a plurality of multiplexing son MH and a plurality of according to the message after the GRE protocol encapsulation, described public information field comprises IP, MAC and PHY;

Wherein, the message after a multiplexing son MH is used for indicating each to encapsulate is at the position of whole message and the length information of the message after each encapsulation.

4. method according to claim 1 is characterized in that,, also comprises before receiving terminal sends described multiplexing encapsulated message at described transmitting terminal: a field is set in multiplexing encapsulated message, and to be used to indicate message be multiplexing encapsulated message.

5. method according to claim 4 is characterized in that, described multiplexing encapsulated message comprises:

Public information field, an a plurality of multiplexing son MH and a plurality of according to the message after the GRE protocol encapsulation; Described public information field comprises IP, MAC and PHY;

Wherein, the message after a multiplexing son MH is used for indicating each to encapsulate is at the position of whole message and the length information of the GRE message after each encapsulation.

6. method according to claim 5 is characterized in that, described to be used for indicating message be that the field of multiplexing encapsulated message is a bit of IP head; Or described to be used to indicate message be the Flag field of field for increasing of multiplexing encapsulated message; Or described to be used for indicating message be that the field of multiplexing encapsulated message is the multiplexed information control bit that is arranged at the GRE head.

7. method according to claim 6 is characterized in that, a described multiplexing son MH is arranged in the GRE head.

8. according to each described method of claim 1-7, it is characterized in that, before transmitting terminal encapsulated according to the GRE agreement respectively a plurality of messages with identical destination address that receive, described method also comprises: the partial information to the GRE head was compressed.

9. method according to claim 8 is characterized in that, also comprises:

Transmitting terminal sends complete message to receiving terminal;

Transmitting terminal sends the compression transfer request message to receiving terminal;

Receiving terminal is preserved packed field, and sends compression acknowledge message to transmitting terminal;

Transmitting terminal is preserved packed field.

10. a dispensing device is characterized in that, comprising:

Encapsulation unit is used for a plurality of messages with identical destination address that receive are encapsulated according to generic route encapsulation (GRE) agreement respectively;

The unit is set, is used for that the message after described a plurality of encapsulation is arranged on the public information field and forms a multiplexing encapsulated message afterwards;

Transmitting element is used for the message after receiving terminal sends multiplexing encapsulation.

11. a kind of dispensing device according to claim 10 is characterized in that, also comprises:

Compression unit before being used for transmitting terminal a plurality of messages with identical destination address that receive being encapsulated according to the GRE agreement respectively, compresses the partial information of GRE head.

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