CN101064667A

CN101064667A - Method for monitoring and adjusting universal routing package tunnel state

Info

Publication number: CN101064667A
Application number: CNA2006100262724A
Authority: CN
Inventors: 汪革; 苟利平
Original assignee: SHANGHAI BAUD DATA COMMUNICATION CO Ltd
Current assignee: SHANGHAI BAUD DATA COMMUNICATION CO Ltd
Priority date: 2006-04-29
Filing date: 2006-04-29
Publication date: 2007-10-31

Abstract

A method of monitoring and adjusting general route encapsulation tunnel state is a GRE keepalive mechanism, the mechanism is accomplished as(RFC 1701), (RFC 1702), and (RFC 2784), and applied in d ata transmission tunnel which adopts GRE protocol. The main content is that it uses data communication equipment which supports GRE function to send keepalive report to realize the monitoring of communication state of receiving end and change the state of tunnel port of sending end GRE terminal dynamically. The purpose of the invention is to increase the efficiency of data transmission and decrease the waste of network resource during the course of two ends of communication which adopts GRE protocol sends data by GRE tunnel.

Description

A kind of monitoring and the method for adjusting universal routing package tunnel state

Technical field:

The present invention relates to a kind of communications field, particularly relate to a kind of based on monitoring under the GRE agreement and the method for adjusting universal routing package tunnel state.

Background technology:

Main GRE (the Generic Router Encapsulation) technology that adopts of existing internet data transmission, it is a kind of for satisfying the tunnel encapsulation agreement that transfer of data is set up.Be mainly used between two end points of network service and set up a gre tunneling.By reaching the purpose of setting up communication tunnel mutually, and realize the transfer of data of this point-to-point transmission by this tunnel in the tunnel of each end mouth configuring GRE agreement.Because this technology has characteristic simply cheaply in its practice, so, having become in the network data communication agreement, IPV4 is to a solution of IPV6 transition.Yet, the GRE tunnel (gre tunneling) that between network endpoint, is set up described in the GRE agreement, itself is from agreement a kind of unsure state of saying so.That is to say that the local GRE end points end points of agreement (adopt GRE) do not preserve any information about opposite end GRE end points.Therefore, this local endpoint does not just know whether the opposite end end points survives.And know in the data communication of reality whether the opposite end survives local endpoint is very useful.No longer survive if know the GRE opposite end, the tunnel mouth that we can this locality is set to the down state.If have a kind of method can realize monitoring to the existing state of opposite end GRE end points in data transmission procedure, and according to the situation of monitoring the tunnel mouth state of this locality is dynamically adjusted, this will bring very big benefit to data communication.For example, when this tunnel mouth was as outer outbound port in the routing table, we can delete this relevant route table items, perhaps even can select the optional route table items of another one to replace the list item of deleting.In addition, no longer survive, can stop to send message, reduce the burden of network service if know the opposite end.

Summary of the invention:

For solving the problems of the technologies described above, the invention provides a kind of monitoring and the method for adjusting universal routing package tunnel state, it is a kind of GRE keepalive mechanism, this mechanism is finished according to " RFC 1701 ", " RFC 1702 " and " RFC 2784 ", is applied to adopt in the data transmission tunnel of GRE agreement.

To be data communications equipment that utilize to support the GRE protocol function send end points by local GRE to content of the present invention sends the keepalive message receiving end communications status that achieves a butt joint and monitor and dynamically change the state of the tunnel mouth of transmitting terminal GRE end points.The effect of this method is to make to adopt the communication two ends of GRE agreement utilizing gre tunneling to carry out in the process of transfer of data, improves the validity of network data transmission and is reduced to the waste of network resources that takies of guaranteeing that transfer of data causes by mechanism of the present invention.

In order to realize above-described inventive method, the concrete steps of this method are:

The timer of a keepalive at first is set at local GRE end points, and every certain hour just sends a keepalive message.Secondly, after a such keepalive message is received in the opposite end, can not handle especially it, only can carry out common GRE decapsulation to it, give upper-layer protocol then and handle (ICMP), ICMP will give an ICMP response message after handling and finishing smoothly, and the icmp packet of this response will form a keepalive response message through the encapsulation process of GRE equally.Certainly, the opposite end does not need necessarily to support keepalive mechanism on mechanism method, treats the keepalive message that the other side sends over like that because it can be handled as the GRE protocol method.If then do not cause not receiving response message behind the local keepalive message that sends because the opposite end does not exist, local GRE end points can be by the timer setting of this locality, every regular hour just sends same keepalive message, but do not receive that before timer expired the keepalive response message that the opposite end sends over will increase an error logging, when surpassing maximum errors number, just indicate that the opposite end gre tunneling no longer exists.At this moment, it is the down state that local GRE end points is provided with the tunnel mouth, is in order dynamically to find the port that may survive again in the opposite end, rebulid to be used for the gre tunneling of transfer of data but also need timed sending keepalive message, the purpose of doing like this.Certainly for this locality is set the time that sends the keepalive message, can does dynamically change according to the network condition of reality.

In addition, the present invention also has following technical characterictic:

1] related communication message is to utilize existing GRE interface of BDCOM and Tunnel interface among the present invention, and code=0, the icmp packet of type=8 type is packaged into the keepalive message format of a GRE message as us with GRE, as shown in Figure 1.

2] the present invention does not make tangible change to network design.If in data transmission procedure, the communication two ends have one or both ends to think configuring GRE keepalive mechanism method simultaneously, as long as these two ends all support the GRE agreement just passable.For both sides, do not need to do any change.It is very little that it uses cost.

3] if GRE keepalive mechanism method is all adopted at the two ends of GRE traffic, then these two ends do not need to carry out synchronously with the timer of the other side's keepalive.That is to say that both sides' keepalive timer can be separate, two ends can be provided with different parameter value.Reduced the complexity of communicating pair on negotiations process and management coupling like this, be easy to use.

Beneficial effect of the present invention is: the method for the invention is not introduced new message kind on the type of keepalive message, reduced the complexity of this mechanism method in concrete enforcement, and made full use of the existing systems function, realized obtaining extra function with design flexible.This method can dynamically be found the state information of GRE opposite end by utilizing transmission and the response to above-mentioned message, with the state information of this corresponding change Tunnel mouth.Simultaneously, this method does not significantly consume as the performance of a kind of mechanism to transfer of data.Its efficient succinct characteristics provide a kind of new more perfect system solution for disposing uniting of IPV6 and IPV4 under the situation that does not increase the existing system complexity.

Description of drawings:

Fig. 1 is the keepalive message format in GRE keepalive mechanism

Fig. 2 is the local keepalive message that sends under the GRE agreement

The response message that the keepalive message that Fig. 3 sends this locality for opposite end under the GRE agreement is sent

Fig. 4 is the data flowchart of the local keepalive of transmission

Fig. 5 is the local deal with data flow process of receiving a keepalive message

Embodiment:

For implementation step of the present invention better is described, specify the workflow of GRE keepalive mechanism method below with reference to accompanying drawing:

As shown in Figure 4, for utilizing the function of GRE keepalive mechanism method, local side sends the keepalive message.In this process, at the beginning according to the keepalive configuration of this locality, start the timer of keepalive itself, retransmitting number of times initialization number is 0.When the timer of keepalive is 0, mean the response message of during this period of time not receiving keepalive, then retransmit number of times and add one.If do not reach maximum number of retransmissions, then construct a keepalive message, need to call GRE in the construction process and encapsulate, and send this keepalive message by the IP layer.If this repeating transmission number of times has surpassed maximum number of retransmissions, then to put local tunnel mouth be the down state to local side, this means that this opposite end no longer survives, and then construct a keepalive message and send, and its process is handled the same.

As shown in Figure 5, for utilizing the function of GRE keepalive mechanism method, local side receives the keepalive message.To be the IP module give the GRE module keepalive message of receiving to its process carries out decapsulation and handle, and message is just delivered to the relevant treatment that the Tunnel module is carried out keepalive then, and resetting timer and putting number of retransmissions is 0.The timerl that waits for keepalive then arrives and sends the keepalive message again, and processing procedure is got back to the processing procedure of top transmission keepalive message.

According to the described inventive method of above execution mode, but concrete configuration is in supporting IPV6 and IPV4 dual-stack router.Under the GRE agreement is supported, if this locality has disposed the keepalive function, then do not need the IPV4/IPV6 router of requirement opposite end necessarily to possess and can realize the keepalive function, do not need time and this locality of keepalive of opposite end configuration consistent yet.Whether dual-stack router that so just can the dynamic monitoring opposite end survives, thereby improves the communication efficiency of IPV6 and IPV4 interconnection.

Above-described only is most preferred embodiment of the present invention, in order to limit all any modifications done within the spirit and principles in the present invention of the present invention, to be equal to replacement and improvement etc., all should not be included within protection scope of the present invention.

Claims

1, a kind of monitoring and the method for adjusting universal routing package tunnel state, this method utilization supports the data communications equipment of GRE protocol function to send end points by local GRE and sends the state that the keepalive message realizes the opposite end communications status is monitored and dynamically changed the tunnel mouth of transmitting terminal GRE end points that the step of this method comprises:

1] timer of a keepalive is set at local GRE end points;

2] the every certain hour of local GRE end points just sends a keepalive message;

3] behind the keepalive message that the receiving terminal of opposite end receives, it is carried out common GRE decapsulation, give upper-layer protocol then and handle (ICMP), ICMP will give an ICMP response message after handling and finishing smoothly, the icmp packet of this response equally will be through the encapsulation process of GRE, form a keepalive response message, the concurrent transmitting terminal of returning.

2, method according to claim 1, it is characterized in that related keepalive message utilizes existing GRE interface of BDCOM and Tunnel interface, code=0, the icmp packet of type=8 type is packaged into the keepalive message format of a GRE message as us with GRE.

3, method according to claim 1, it is characterized in that the timer setting that the GRE end points of transmitting terminal can be pressed transmitting terminal in implementation process of this method, every regular hour just sends same keepalive message, but do not receive that before timer expired the keepalive response message that receiving terminal sends over will increase an error logging, when surpassing maximum errors number, just indicate that the opposite end gre tunneling no longer exists, at this moment, it is the down state that transmitting terminal is provided with the tunnel mouth, but also need timed sending keepalive message, so that in order dynamically to find the port that receiving terminal may be survived again, rebulid to be used for the gre tunneling of transfer of data.

4, method according to claim 1 is characterized in that transmitting terminal related in this method is provided with the time that sends the keepalive message, can do dynamically change according to the network condition of reality.

5, inventive method according to claim 1 is characterized in that this method can be disposed at the one or both ends of communication in actual applications simultaneously.

6, method according to claim 1, it is characterized in that if this mechanism method is disposed at the two ends of communication simultaneously in actual applications, then these two ends do not need to carry out synchronously with the timer of the other side's keepalive, both sides' keepalive timer can be separate, and two ends can be provided with different parameter value.