ccna 200 301 ppt

ccna 200 301 ppt.RFC1065 came out in 1988: Structure and Identification of Management Information for the TCP/IP-based Internet. The most valuable idea behind this document is that devices on a TCP/IP-based network can be broken down into to a database of variables that can be monitored to manage the entire IP-based network. In short, any element of an IP-based mechanism has some commonalities. For example, a PC, a network printer, and a router all have some commonalities, such as interfaces, IP addresses, and caching. Why not create a standard database of variables and a simple system to monitor and manage them? The idea was great, simple to understand, and evolved into three different versions of the Simple Network Management Protocol (SNMP).Description SNMPThe Simple Network Management Protocol is an application layer protocol that defines a message format for communication between a so-called manager and an agent. An SNMP manager is a network management application running on a PC±, while an agent is a piece of software running on a managed device. The agent's job is to retrieve (and possibly write) the variables stored in the variable database that make up the device parameters. This database is called the Management Information Base (MIB). Cisco Prime is a classic example of an SNMP manager. Cisco routers may run SNMP agents, and MIB variables can be loaded onto the router's interfaces. Figure 19-1 shows these elements of the SNMP environment./, MIB; SfflSNMP Manager Cisco routers and (for example, Sijing P e) SNMP agent softwareFigure 19-1 Elements of the Simple Network Management ProtocolBy periodically polling or polling the SNMP agent on the device, you can collect and analyze statistics about the managed device. You can even reconfigure the device with these SNMP variables in the MIB, if this level of control is allowed. Messages that poll information from the SNMP agent software are referred to in terminology as GET messages, and messages that write variables are referred to as SET messages.11.2 Basic Content 393SNMP allows more flexibility in how variables in the MIB are monitored. Typically, network administrators use Network Management Workstation (NMS) software, such as Cisco Prime, to collect and store statistics at all times. The most important thing for the administrator is to analyze various statistical facts, such as averages, minima, and maxima. For proactive management, administrators can set thresholds for certain key variables. The NMS dynamically notifies the administrator when the value approaches an impermissible range. Figure 19-2 illustrates the use of SNMP for proactive network management.