CN104283916A - A data message transmission method and device applied to HFC network - Google Patents

Abstract

The invention relates to a data message transmission method applied to an HFC network, comprising: a gateway and a client negotiate an identification mode of a data message flow to be transmitted, and synchronize the context information of the data message flow; the client records the The context information corresponding to the data packet flow; the gateway compresses the packet of the data packet flow to be transmitted, and adds a packet flow identifier to the compressed data packet according to the identification method of the data packet flow, and then sends it to the client ; The client reads the packet flow identifier according to the identifier of the data packet flow, and then identifies the data packet flow to which the received data packet belongs according to the packet flow identifier. The invention utilizes the characteristic of no routing and forwarding in the HFC network to compress the IP header of the three-layer message or the Ethernet header and all fields of the IP header of the two-layer message, thereby improving the network transmission efficiency.

Description

A data message transmission method and device applied to HFC network

technical field

The invention relates to the communication field, in particular to a data message transmission method and device applied to an HFC network.

Background technique

The development of IP technology has solved the intercommunication and interconnection problem of heterogeneous networks, and provided a unified network layer bearing platform for applications on various networks. IP is the general trend of network development. The transmission stream of the new generation coding technology (H.264, AVS, VC-1, etc.) is based on the IP format, so the front-end must be IP-based, and the IP-based front-end will inevitably drive the IP-based transmission network. The final trend is that the entire network Of course, the IP of the cable TV network is also included.

Developing IP data services on the cable TV network can give full play to the advantages of wide coverage and high bandwidth of the cable TV network to meet the increasing bandwidth requirements of users. However, the cable TV network has a tree structure, and there is no routing and forwarding. Therefore, the IP header and Ethernet header used for routing addressing in the cable TV network appear redundant, which wastes bandwidth resources and reduces the effective utilization of bandwidth.

In terms of IP header compression technology, some scholars have proposed methods such as VJHC, IPHC, CRTP, and ROHC, which are widely used in wireless networks. However, the above compression methods all use complex encoding methods, and the terminal needs to maintain and update context information. , is not flexible enough, and is not optimized for the application scenarios of the HFC network.

Therefore, how to propose a data message transmission method applied to the HFC network is an urgent problem to be solved.

Contents of the invention

The purpose of the present invention is to overcome the defect that the data message transmission method used in the HFC network in the prior art is not flexible enough and the efficiency is not high, thereby providing a data message transmission method and device applied to the HFC network to utilize wired The TV network does not have the feature of routing and forwarding. It compresses the Ethernet header and IP header of the two-layer message, or compresses the IP header of the three-layer message to improve the transmission efficiency.

In order to achieve the above object, the present invention provides a data message transmission method applied to HFC network, comprising:

Step 1), the gateway and the client negotiate the identification mode of a data packet flow to be transmitted, and synchronize the context information of the data packet flow; wherein, the context information includes the identification method corresponding to the data packet flow, the The unique identifier corresponding to the data packet flow, and the header information of the data packet flow;

Step 2), the client records the context information corresponding to the data packet flow;

Step 3), the gateway compresses the data packets in the data packet flow to be transmitted, and adds a packet flow to the compressed data packet according to the identification method of the data packet flow negotiated in step 1) ID, and then sent to the client;

Step 4), the client reads the packet flow identifier according to the identifier of the data packet flow negotiated in step 1), and then identifies the data packet flow to which the received data packet belongs according to the packet flow identifier.

Among the above-mentioned technical solutions, it also includes:

Step 5), when the client needs to restore the data header, restore the data header according to the context information obtained in step 1).

In the above technical solution, the step 1) includes the following steps:

Step 1-1), the gateway sends a negotiation message to the client, and the negotiation message includes the identification mode of the data packet stream that the gateway can support;

Step 1-2), after receiving the negotiation message, the client selects a certain identification method from the identification methods of the data packet flow supported by the gateway contained in the negotiation message; Header restoration;

Step 1-3), the client notifies the gateway of the result selected in step 1-2) through a negotiation reply message;

Step 1-4), the gateway sends the context message corresponding to the data packet flow to the client.

In the above-mentioned technical solution, the data message includes a two-layer Ethernet message or a three-layer IP message; wherein, the two-layer Ethernet message includes a header and an IP load, and the header includes an Ethernet frame header and an IP header; The above-mentioned three-layer IP packet includes a header and an IP payload, wherein the header includes an IP header.

In the above technical solution, in the step 3), the gateway compressing the data packets in the data packet stream to be transmitted includes: for the three-layer IP packet, removing the header in the IP packet, and only retaining IP payload; for Layer 2 Ethernet packets, the Ethernet header and IP header in the Ethernet packet are removed, and only the IP payload is retained.

In the above technical solution, the identification method includes: using an idle field of the encapsulation protocol in the HFC network to uniquely identify the data packet flow, or adding an identification field before the IP payload to uniquely identify the data packet flow.

In the above technical solution, the step 5) includes:

When adopting the idle field in the encapsulation protocol in the HFC network to mark the data message flow, if the data message is a three-layer IP message, then add a three-layer IP header before the received data message; If the data message is a two-layer Ethernet message, add a three-layer IP header and a two-layer Ethernet header before the received data message;

When adopting to add the identification field before the IP load to identify the data message flow, if the data message is a three-layer IP message, then remove the identification field, and add a three-layer IP header in front of the remaining data; If the above data message is a Layer 2 Ethernet message, the identification field is removed, and a Layer 3 IP header and a Layer 2 Ethernet header are added in front of the remaining data.

The present invention also provides a data message transmission device applied to the HFC network, including: a gateway and a terminal client, wherein,

The gateway notifies the client of the supported data packet flow identification method, notifies the client of the context information of the data packet flow, then compresses the data packet and converts the compressed data packet into a compressed data packet according to the agreed packet flow identification method. Add a message flow identifier to the file, and send the compressed message to the client;

The client saves the context information of the data message flow, receives the compressed message, and restores the data message according to the context information of the data message flow.

The advantages of the present invention are:

1. Utilizing the non-routing and forwarding feature of the HFC network, the IP header of the layer 3 message or the Ethernet header and all fields of the IP header of the layer 2 message are compressed, which improves the network transmission efficiency.

2. It does not need to consider the type of the payload of the data message, and supports TCP, UDP and other transport layer protocol formats.

3. The client can flexibly choose whether to restore the header of the data packet according to the application requirements, and further simplifies the situation that does not need to be restored.

Description of drawings

Fig. 1 is a flow chart of the implementation steps of the inventive method in one embodiment;

Fig. 2 is a schematic diagram of negotiation between the gateway and the client;

Fig. 3 is a schematic diagram of comparison before and after IP packet compression;

Fig. 4 is a schematic diagram of the segment format of the multi-protocol encapsulation MPE;

Fig. 5 is a flow chart of the implementation steps of the method of the present invention in yet another embodiment;

Fig. 6 is a schematic diagram of comparison before and after Ethernet packet compression.

Detailed ways

The present invention will be further described now in conjunction with accompanying drawing.

In one embodiment, the HFC network adopts the IP over DVB encapsulation protocol, in which the multi-protocol encapsulation protocol MPE is adopted.

The implementation steps of the method of the present invention in this embodiment will be described below with reference to FIG. 1 .

Method of the present invention comprises the following steps:

Step 101), the gateway and the terminal client negotiate the identification mode of the IP packet flow, and synchronize the context information of the IP packet flow;

Step 102), the client records the context information corresponding to the IP packet flow;

Step 103), the gateway compresses the IP message to be sent, and adds a message flow identifier to the compressed IP message, and then sends it to the client;

Step 104), the client reads the packet flow identification according to the identification method of the IP packet flow negotiated in step 1), and then identifies the IP packet flow to which the received IP packet belongs. If the terminal needs to restore the IP header, then according to The context information obtained in step 101) restores the IP header.

The relevant steps of the method are further described below.

As shown in Figure 2, the step 101) specifically includes the following steps:

Step 101-1), the gateway sends a negotiation message to the client, and the negotiation message includes the identification mode of the IP packet flow that the gateway can support;

There are many ways to identify the IP message flow that the gateway can support. For example, use the idle field of the encapsulation protocol in the HFC network for unique identification, or add an identification field before the IP payload for unique identification. In this embodiment, the idle field in the MPE can be used to identify the IP packet flow. Figure 4 shows the segment format of the multi-protocol encapsulation MPE, in which the "MAC6, 5 field" is an idle field, and the client can use this field to identify the IP packet flow.

Step 101-2), after receiving the negotiation message, the client selects a certain identification method from the identification methods of the IP packet flow supported by the gateway included in the negotiation message; in addition, it determines whether Perform IP header restoration;

Step 101-3), the client notifies the gateway of the result selected in step 101-2) through a negotiation reply message;

Step 101-4), the gateway sends the context message corresponding to the IP packet flow to the client.

The context information corresponding to the IP packet flow involved in this step includes: the identification mode corresponding to the packet flow, the unique identifier corresponding to the packet flow, and the IP header information of the packet flow. Wherein, the IP header information of message flow is the necessary information when the terminal needs to restore the header; the unique identifier of IP message flow is assigned by the gateway for each IP message flow. In this embodiment, the unique identifier has 2 Byte size, recyclable.

In said step 103), the gateway compressing the IP message to be sent includes: removing the header in the IP message, and only retaining the IP payload. Figure 3 shows the comparison before and after IP packet compression.

In the step 103), adding a packet flow identifier to the compressed IP packet includes: storing the unique identifier assigned by the gateway to the IP packet flow where the IP packet is located in the multi-protocol encapsulation MPE The "MAC6,5" field in .

Said step 104) includes:

Step 104-1), after the client receives the data stream of a certain compressed IP message, assemble the data in this data stream into a multi-protocol encapsulation segment, and use the "MAC6, 5 field" to read The unique identifier of the outgoing IP packet flow;

Step 104-2), classify the received IP packets according to the unique identifier of the IP packet flow read in step 104-1), and identify the IP packet flow to which the IP packet belongs.

If the IP message still needs to restore the IP header, the step 104) also includes:

Step 104-3), adding an IP header to the front end of the compressed IP message according to the context information obtained in step 101).

In yet another embodiment of the present invention, the method of the present invention is described by taking the EoC solution in the HFC network as a scenario. As shown in Figure 5, the method of the present invention comprises the following steps:

Step 201), the gateway and the terminal client negotiate the identification mode of the Ethernet packet flow, and synchronize the context information of the Ethernet packet flow;

Step 202), the client records the context information corresponding to the Ethernet packet flow;

Step 203), the gateway compresses the Ethernet message to be sent, and adds a message flow identifier to the compressed Ethernet message, and then sends it to the client;

Step 204), the client reads the packet flow identifier according to the identifier of the Ethernet packet flow negotiated in step 201), and then identifies the Ethernet packet flow to which the received Ethernet packet belongs. If the terminal needs to restore the Ethernet header, then according to The context information obtained in step 201) restores the Ethernet header.

The relevant steps of the method are further described below.

The step 201 includes:

Step 201-1), the gateway sends a negotiation message to the client, and the negotiation message includes the identification mode of the Ethernet packet flow that the gateway can support;

Step 201-2), after receiving the negotiation message, the client selects a certain identification method from the identification methods of the Ethernet packet flow supported by the gateway included in the negotiation message; in addition, it determines whether to Perform Ethernet header restoration;

In this embodiment, the identification method of the Ethernet packet flow adopts the method of adding an identification field before the IP payload for unique identification.

Step 201-3), the client notifies the gateway of the result selected in step 201-2) through a negotiation reply message;

Step 201-4), the gateway sends the context message corresponding to the Ethernet packet flow to the client.

The context information corresponding to the Ethernet packet flow involved in this step includes: the identification mode corresponding to the packet flow, the unique identifier corresponding to the packet flow, the Ethernet header and the IP header information of the packet flow. Wherein, the Ethernet header and the IP header of the message flow are necessary information when the terminal needs to restore the header.

In step 203), the gateway compressing the Ethernet message to be sent includes: removing the Ethernet header and IP header in the Ethernet message, and only retaining the IP payload. In the step 203), adding the packet identifier to the compressed Ethernet packet includes: adding the packet flow identifier before the IP payload. FIG. 6 is a schematic diagram of an Ethernet packet before compression and after compression and adding a packet identifier.

The step 204) includes:

Step 204-1), after the client receives the data stream of a certain compressed Ethernet message, it reads the Ethernet message stream to which the compressed Ethernet message belongs from the first 2 bytes of the message. Uniquely identifies.

Step 204-2), classify the received Ethernet packets according to the unique identifier of the Ethernet packet flow read in step 204-1), and identify the Ethernet packet flow to which the Ethernet packet belongs.

If the Ethernet packet still needs to restore the Ethernet header, the step 204) also includes:

Step 204-3), adding the Ethernet header and IP header to the front end of the compressed Ethernet packet according to the context information obtained in step 201).

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than limit them. Although the present invention has been described in detail with reference to the embodiments, those skilled in the art should understand that modifications or equivalent replacements to the technical solutions of the present invention do not depart from the spirit and scope of the technical solutions of the present invention, and all of them should be included in the scope of the present invention. within the scope of the claims.

Claims (8)

1. be applied to a data message transmission method for hfc plant, comprise:

The identification means of a certain data message stream waiting for transmission of step 1), gateway and client negotiate, the synchronously contextual information of this data message stream; Wherein, described contextual information comprises the header information of identification means corresponding to this data message stream, unique identification that this data message stream is corresponding, this data message stream;

Step 2), contextual information that this data message stream of client records is corresponding;

Step 3), gateway compress the data message in described data message stream waiting for transmission, and according to the identification means of the data message stream consulted in step 1) be compression after data message add message flow mark, then send to client;

Step 4), client read message flow mark according to the identification means of the data message stream consulted in step 1), and then identify the data message stream belonging to received data message according to this message flow mark.

2. the data message transmission method being applied to hfc plant according to claim 1, is characterized in that, also comprise:

Step 5), when client needs restoring data header, according to the contextual information restoring data header obtained in step 1).

3. the data message transmission method being applied to hfc plant according to claim 1 and 2, is characterized in that, described step 1) comprises the following steps:

Step 1-1), gateway sends negotiation message to client, comprises the identification means of the data message stream that gateway can be supported in this negotiation message;

Step 1-2), after client receives described negotiation message, the identification means of the data message stream that the gateway comprised from described negotiation message can be supported, choose a certain identification means; Determine whether as required to carry out datagram header reduction;

Step 1-3), client is by step 1-2) selected in result reply message informing gateway through consultation;

Step 1-4), gateway to send datagram context message corresponding to stream to client.

4. the data message transmission method being applied to hfc plant according to claim 1 and 2, is characterized in that, described data message comprises two layers of Ethernet message or three layers of IP message; Wherein, described two layers of Ethernet message comprise header and IP load, and header wherein comprises ether frame head and IP head; Described three layers of IP message comprises header and IP load, and header wherein comprises IP head.

5. the data message transmission method being applied to hfc plant according to claim 4, it is characterized in that, in described step 3), gateway carries out compression to the data message in described data message stream waiting for transmission and comprises: for three layers of IP message, remove the header in IP message, only retain IP load; For two layers of Ethernet message, remove the Ethernet header in Ethernet message and IP head, only retain IP load.

6. the data message transmission method being applied to hfc plant according to claim 4, it is characterized in that, described identification means comprises: utilize the idle field of tunneling in hfc plant to carry out unique identification data message flow, or before IP load, adds identification field carry out unique identification data message flow.

7. the data message transmission method being applied to hfc plant according to claim 6, is characterized in that, described step 5) comprises:

When adopting the idle field in hfc plant in tunneling to identify data message flow, if described data message is three layers of IP message, then before received data message, add three layers of IP head; If described data message is two layers of Ethernet message, then before received data message, add three layers of IP head and two layers of Ethernet header;

When adopt add before IP load identification field data message flow is identified time, if described data message is three layers of IP message, then remove identification field, before remaining data, add three layers of IP head; If described data message is two layers of Ethernet message, then remove identification field, before remaining data, add three layers of IP head and two layers of Ethernet header.

8. be applied to a data-message transmission device for hfc plant, it is characterized in that, comprising: gateway and client terminals, wherein,

The data message traffic identifier mode that it supports by described gateway notifies client, by the contextual information of data message stream notice client, then the packed data message message flow identification means that also basis is decided through consultation is the data message interpolation message flow mark after compression, and the message after compressing is sent to client;

Described client preserves the contextual information of data message stream, and receive the message after compression, if need restoring data message, client is reduced according to the contextual information of this data message stream.