CN1298137C - Proxy network management realizing method based on SNMP protocol - Google Patents

Abstract

A method for realizing agent network management based on the SNMP protocol in a distributed network communication device system, characterized in that: in the distributed network communication system, an agent network management server is set, and the public network IP address and Private network IP address, the managed device is configured with a private network IP address, the network management station realizes routing with the proxy network management server through the public network IP address, the proxy network management server and the managed device realize routing through the private network IP address, and through the proxy network management server The processing and forwarding of the SNMP message completes the communication between the network management station and the managed device; the network management station sends the SNMP request message to the agent network management server, and the format of the community field in the SNMP agent request message also includes forwarding The required additional information reflects the information of the managed equipment; the invention provides an economical and effective realization method for network management of network elements in a distributed network communication system.

Description

A Realization Method of Proxy Network Management Based on SNMP Protocol

technical field

The invention relates to a method for realizing a proxy network management, in particular to a method for realizing a proxy network management based on the SNMP protocol in a distributed network communication device system.

Background technique

At present, almost all network communication devices have the simple network management protocol SNMP, that is, the Simple Network Management Protocol network management function. The SNMP network management system consists of the network management workstation NMS, namely the Network Management Station, and the network management agent SNMP running on the managed device The SNMP Agent and the NMS communicate through the standard SNMP protocol. The SNMP network management system can complete the configuration management, performance management and fault management of the managed devices.

For distributed network communication systems, such as wireless local area network WLAN, that is, WirelessLocal Area Network network system, operators will plan many hotspots in each city when constructing WLAN networks, and arrange a certain number of hotspots in each hotspot according to needs. The wireless access point AP, that is, Access Point, these AP devices and other network devices form a huge distributed network, and network management is required for each AP device in the network.

In such a distributed network communication system, in order to realize the SNMP network management of each network element, there are two methods currently adopted:

1. Configure a public network IP address on each network element. Although this can realize remote centralized management, due to the large number of network elements, it will occupy a lot of public network IP addresses. The current public network IP address resources are already very tight , so the cost of this approach is very high.

2. Configure the private network IP address on the network element, and set up a network management workstation in each hotspot area to realize the network management of all network elements in the hotspot. This will not only cause too much waste of resource configuration on the network management workstation, but also cannot realize remote centralized management.

Contents of the invention

The purpose of the present invention is to provide a method for realizing the proxy network management based on the SNMP protocol, so as to solve the shortcomings of the waste of public network IP addresses and the inability to realize remote centralized management in the prior art, and provide a solution for network elements in distributed network communication systems. Network management provides a cost-effective means of doing so.

The realization method of the proxy network management based on SNMP protocol adopted in the present invention is that in the distributed network communication system, a proxy network management server is set, and a public network IP address and a private network IP address are configured on the proxy network management server simultaneously, and the managed device Configure the private network IP address. The network management station implements routing with the proxy network management server through the public network IP address. The proxy network management server and the managed device realize routing through the private network IP address. Complete the communication between the network management station and the managed equipment;

When the network management station accesses the management information base on the managed device through the proxy network management server, it constructs an SNMP proxy request message, and sends the request message to the proxy network management server, and the community in the SNMP proxy request message The field contains the additional information required for SNMP message forwarding. After receiving the SNMP request message, the proxy network management server generates a new SNMP request message according to the additional information and forwards it to the real managed device. , the managed device returns an SNMP response message to the proxy network management server, and the proxy network management server restores the original information in the response message and forwards it to the corresponding network management station;

Described additional information comprises the SNMP version number and community supported by the SNMP Agent on the managed device and the working IP address and UDP port number of the SNMP Agent on the managed device;

After receiving the SNMP request message, the proxy network management server performs ASN.1 decoding on the request message, parses out the additional information therein, and records the relevant original information in the proxy request message, according to the additional information parsed out Modify the version and community fields in the original SNMP request message, renumber the request-id, re-encode ASN.1 to generate a new SNMP request message, and forward the new SNMP request message to the real management device, and record the relevant status and request-id information of the forwarded SNMP request message;

When the proxy network management server performs ASN.1 decoding on the request message, the community field is checked for validity. If there is a proxy request flag in the community field, it is considered to be an SNMP proxy request message, otherwise it is regarded as an ordinary SNMP request message. deal with;

If the community field is in the format of proxy@vx@cstring@addr@port, it is considered as an SNMP proxy request message. The proxy@ prefix is the symbol of the proxy request message, and vx is supported by the managed device SNMP version number, cstring is the community string on the managed device, addr and port are the working IP address and UDP port number of the SNMP Agent on the managed device;

After the described managed device receives the SNMP request from the proxy network management server, it performs the corresponding management information base access operation, constructs an SNMP response message, and sends the response message to the proxy network management server, and the proxy network management server receives and returns After decoding, match the stored information according to the request-id field in the response message. If the match is successful, restore the original values of the relevant fields such as version, community, and request-id in the message. , re-encode the message, and then forward it to the corresponding network management station;

When the request-id field is matched in the stored information, if the match is unsuccessful, the message is discarded;

If an alarm or failure occurs on the managed device, the SNMP Trap message is sent to the agent network management server in real time, and the agent network management server forwards the SNMP Trap message to the network management station after receiving it.

The beneficial effects of the present invention are: in the present invention, since the interface between the agent network management server and the network management station, and the interface between the agent network management server and the managed equipment are all standard SNMP protocol interfaces, so the present invention proposes The implementation method of the proxy network management based on the SNMP protocol has no special requirements for the managed device and the network management station. It only needs to select a device among the existing devices as the proxy network management server, which is the network of network elements in the distributed network communication system. Management provides a cost-effective means of implementation.

Specifically, the present invention has the following advantages:

1. Save a lot of public IP addresses; there is no need to configure a public IP address on each managed device, only the proxy network management server occupies the public IP address.

2. It meets the requirements of remote management and centralized management. There is no need to set up a network management station locally on the managed device. The network management station can be configured centrally, and the remote management and monitoring of the network can be realized through the proxy network management server.

3. In the present invention, the interface between the proxy network management server and the network management station and the interface with the managed equipment are standard SNMP interfaces, which have very good versatility and flexibility, and are applicable to various In a system composed of network communication devices.

4. The principle of the invention is simple, the development difficulty is small, and the investment cycle is short.

Description of drawings

Figure 1a is a schematic diagram of the format of an SNMP request message;

Figure 1b is a schematic diagram of the PDU format of the SNMP request message;

Fig. 2 is the schematic diagram of the management model of agent network management of the present invention;

Fig. 3 is a schematic diagram of the processing flow of the proxy network management server in the present invention.

Detailed ways

Below according to accompanying drawing and embodiment the present invention will be described in further detail:

In the actual operation and networking of wireless LAN devices, wireless access points AP and access controller AC, that is, Access Controller, are generally used. APs are used as devices with a large number and scattered distribution. Configured as a private network IP address, the AC acts as a centralization and control device for user wireless access, and realizes functions such as user authentication, management, and accounting. The number of AC devices is relatively small, and the distribution of devices is relatively concentrated. The network side interface configuration of the AC It is a public network IP address, and the user-side interface is configured as a private network IP address. The user-side interface is connected to the Ethernet interface of the AP through a wired method, and can communicate with the AP. Since the carrier's network management center is located on the public network, the route between the AC and the network management center is reachable, but because the AP has a private network address, the route to the network management center is not reachable.

Based on the equipment factors of the above-mentioned actual operation, in the present invention, as shown in Figure 2, the AC is used as the SNMP proxy network management server SNMP Proxy Agent, and the AP is used as the real managed device SNMP Proxy Target. The public network IP address and the private network IP address are configured on the Proxy Agent at the same time. The managed device SNMP Proxy Target is configured with the private network IP address. The network management station NMS realizes routing with the proxy network management server through the public network IP address. Routing is realized through the private network IP address, and the communication between the network management station and the managed device is completed through the processing and forwarding of SNMP messages by the proxy network management server.

As a bridge between the network management station and the managed device, the proxy network management server mainly plays the role of processing and forwarding SNMP messages. After processing the SNMP request message received from the network management station, it forwards it to the corresponding managed device. The SNMP response message returned by the managed device is processed and forwarded to the NMS.

As shown in Figure 3, the specific processing flow is as follows:

When the network management station accesses the management information base on the managed device through the proxy network management server, it constructs an SNMP proxy request message and sends the request message to the proxy network management server. The format of the SNMP proxy request message still strictly follows the standard SNMP message The format of the entire SNMP message shown in Figure 1a, where the protocol data unit PDU, that is, the format of the Protocol Data Unit is shown in Figure 1b, for different types of SNMP PDU, such as GetRequest PDU, GetNextRequest PDU, SetRequest PDU etc., all comply with the PDU format shown in Figure 1b, the PDU type field identifies their types, and the request object identifier OID bound in the variable binding list variable-bindings of the proxy request message, that is, the ObjectIdentifier is the real The OID instance on the managed device, the format of the community field in the SNMP agent request message also includes additional information required for forwarding, reflecting the managed device information, such as the SNMP version number supported by the SNMP Agent on the managed device and the community and the working IP address and UDP port number of the SNMP Agent on the managed device.

After the proxy network management server receives the SNMP request message, it performs ASN.1 decoding on the request message. Since the proxy network management server has both a common SNMP Agent and a network management proxy function, the proxy network management server is not responsible for receiving the SNMP request. The SNMP request message must distinguish whether it is a normal SNMP request or an SNMP proxy request. This distinction is realized by parsing the community field in the SNMP request message.

First check the validity of the community field. If the community field has a proxy request flag, it is considered to be an SNMP proxy request message, otherwise it will be processed as a normal SNMP request message; the community field is proxy@vx@cstring@addr@port format, it is considered as an SNMP proxy request message, where the proxy@ prefix is the symbol of the proxy request message, vx is the SNMP version number supported by the managed device, and the value is v1 or v2, and cstring is the SNMP version number on the managed device community string, addr and port are the working IP address and UDP port number of the SNMP Agent on the managed device respectively, and the SNMP agent request message will be forwarded to this IP address and port through the proxy network management server; the proxy network management server parses out the SNMP request message The additional information in the text, and record the relevant original information in the proxy request message, modify the version and community fields in the original SNMP request message according to the additional information parsed, and renumber the request-id, and re-do the ASN. 1 After encoding, generate a new SNMP request message, forward the new SNMP request message to the real managed device, set the timer for waiting for the response message from the managed device, and record the forwarded SNMP request The relevant state of the message and the request-id and other information are in the Proxy global control linked list, and the processing of the SNMP request is ended.

After receiving the SNMP request from the proxy network management server, the managed device performs the corresponding management information base access operation, constructs an SNMP response message, sends the response message to the proxy network management server, and receives the returned SNMP response on the proxy network management server After decoding the message, match the information stored in the Proxy global control list according to the request-id field in the response message. If the match is successful, restore the original version, community, request-id and other related fields in the message. value, re-encode the message, and then forward it to the corresponding network management station; if the match fails, it means that the response message has timed out, and the message is discarded.

If an alarm or fault occurs on the managed device, it means that some kind of alarm occurs on a managed device connected to the proxy network management server, and then the SNMP Trap message will be sent to the proxy network management server in real time, and the proxy network management server will not stop after receiving it. Change the content in the SNMP Trap message and directly forward the SNMP Trap message to the network management station.

Claims (7)

1. implementation method based on the agent network management of snmp protocol, it is characterized in that: in the distributed network communication system, the agent network management server is set, on this agent network management server, dispose public network IP address and private network IP address simultaneously, managed device configuration private network IP address, network management workstation is realized route by public network IP address and agent network management server, realize route by private network IP address between agent network management server and the managed device, by of processing and the forwarding of agent network management server, finish communicating by letter between network management workstation and the managed device to the SNMP message; Described network management workstation is during by the management information bank on the agent network management server access managed device, structure SNMP proxy requests message, and this request message sent to the agent network management server, comprise the SNMP message in the community field in the described SNMP proxy requests message and transmitted needed additional information, the agent network management server is after receiving the SNMP request message, according to the new SNMP request message of additional information generation wherein, and it is forwarded on the real managed device, managed device returns the SNMP back message using to the agent network management server, the agent network management server recovers the raw information in the back message using, and it is forwarded on the corresponding network management workstation; Described additional information comprises the work IP address of SNMP Agent on SNMP Agent is supported on the managed device SNMP version number and community and the managed device and udp port number.

2. the implementation method of the agent network management based on snmp protocol according to claim 1, it is characterized in that: described agent network management server is after receiving the SNMP request message, request message is carried out the ASN.1 decoding, parse additional information wherein, and the relevant raw information in the record proxy requests message, revise version and community field in the original SNMP request message according to the additional information that parses, and request-id is numbered again, again carry out ASN.1 coding back and generate new SNMP request message, and new SNMP request message is forwarded on the real managed device, and the correlation behavior and the request-id information of the SNMP request message transmitted of record.

3. the implementation method of the agent network management based on snmp protocol according to claim 2, it is characterized in that: when described agent network management server carries out the ASN.1 decoding to request message the community field is carried out validity check, if have the proxy requests sign in the community field, then think SNMP proxy requests message, otherwise handle as common SNMP request message.

4. the implementation method of the agent network management based on snmp protocol according to claim 3, it is characterized in that: described community field is the form of proxy@vx@cstring@addr@port, then think SNMP proxy requests message, described proxy@ prefix is the sign of proxy requests message, the SNMP version number that vx is on the managed device to be supported, cstring is the community character string on the managed device, and addr and port are respectively the work IP address of SNMP Agent on the managed device and udp port number.

5. the implementation method of the agent network management based on snmp protocol according to claim 2, it is characterized in that: described managed device receives from carrying out corresponding management information bank accessing operation after the SNMP of the agent network management server request, structure SNMP back message using, back message using is issued the agent network management server, receive the SNMP back message using that returns on the described agent network management server, mate in the information of being preserved according to the request-id field in the back message using decoding back, if the match is successful, then recover the version in this message, community and request-id field original value, again carry out the coding of message, be forwarded to then on the corresponding network management workstation.

6. the implementation method of the agent network management based on snmp protocol according to claim 5 is characterized in that: when described request-id field is mated in the information of being preserved, if coupling is unsuccessful, then abandon this message.

7. according to the implementation method of claim 3 or 4 or 5 or 6 described agent network managements based on snmp protocol, it is characterized in that: if alarm or fault take place on the described managed device, then send SNMP Trap message to the agent network management server in real time, again this SNMP Trap message is forwarded to network management workstation after the agent network management server receives.

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