Chapter 25 SNMP: SNMP
25.1 Introduction
With the rapid development of network technology, the number of networks is also increasing. The network equipment from various manufacturers, how to manage these devices becomes very important. This chapter is to introduce management criteria for these devices.
TCP / IP based network management consists of two parts: a network management station (also called management process, manager) and a managed network element (also called the managed device). Wide range of managed devices, for example: a router, X terminals, terminal servers and printers. These devices have in common is managed are running TCP / IP protocol. It is managed devices and related management software called the agent (agent) or proxy process. Workstation station usually with color monitor, can display the status of all managed devices (e.g., the connection is dropped, various traffic conditions and the like on the connection).
Communication between the management process and proxy process can have two ways. One is the management process a request to the proxy process, ask a specific parameter value (for example:? You had a number of ICMP port unreachable). Another way is to take the initiative to report to the agent process management process has some important event occurs (for example: a connection port is down). Of course, some may ask management process in addition to the proxy process parameter values outside, it can be changed as desired agent process parameter values (for example: the default IP TTL value to 64).
TCP / IP based network management consists of three components:
- A MIB MIB (Management Information Base). MIB contains all the agent process all can be queried and modified parameters. RFC 1213 [McCloghrie and Rose 1991] defines a second version of the MIB, called the MIB - II.
- MIB on a common structure and representation symbols. Called the Structure of Management Information SMI (Structure ofManagement Information). This is defined in RFC 1155 [Rose and McCloghrie 1990] In. For example: SMI counter is defined a non-negative integer, which counts from 0 to 4294967295, upon reaching the maximum value, and from 0 to start counting.
- The communication protocol between the management process and proxy process, called SNMP SNMP (Simple Network Management Protocol). In RFC 1157 [Case et al. 1990] is defined. SNMP datagram format includes exchange. Although you can use a variety of protocols at the transport layer, but in SNMP, the most used protocol or UDP.
RFC mentioned above is called defined SNMP SNMP v1, or called SNMP, which is the main content of this chapter. Until 1993, there are some new SNMP on the RFC publication. These are defined in RFC termed a second version of SNMP SNMP (SNMP v2), which is discussed in 25. 12 section.
This chapter begins by agreement between the management process and proxy process, and then discuss the data type of the parameter. Use of the term already appeared in this chapter, such as: IP, UDP and TCP and so on. We will give some examples of narrative to help the reader understand these examples, and certain sections of previous related.
