Information Technology Reference
In-Depth Information
Simple Network Management Protocol (SNMP) is an IP application layer protocol that has
become the standard for the exchange of management information between network de-
vices. SNMP was initially described in RFC 1157. It is a simple solution that requires little
code to implement, which allows vendors to build SNMP agents on their products.
Key
To p i c
SNMP runs over User Datagram Protocol (UDP) and therefore does not inherently provide
for s equenc ing and ack nowledg ment of packets, but it st ill reduce s the amount of over -
head used for management information.
SNMP Components
SNMP has three network-managed components:
The managed devices
■
The agent that resides on the managed device
■
The NMS
■
Figure 15-1 shows the relationship between these components.
Network Management
System
SNMP
Messages
Agent
Agent
Managed
Device
Managed
Device
Figure 15-1
SNMP Components
A managed device is a router or LAN switch or any other device that contains an SNMP
agent. These devices collect and store management information and make this information
available to the NMS. SNMP community strings (passwords) are configured on routers
and switches to allow for SNMP management.
The agent is the network management software that resides in the managed device. The
agent gathers the information and puts it in SNMP format. It responds to the manager's re-
quest for information and also generates traps.
