Download ppt

SNMP
Simple Network Management Protocol
Haris Ribic
Objectives

History

What is SNMP?

Management Station

Management Agent

Management Information Base

Network Management Protocol

How does SNMP work?

Architecture

Bibliography
History

Networks became vital and more complicated


Simple Gateway Monitoring Protocol (SGMP)



Cannot be managed by human effort alone
Did not work with equipment from different vendors
Internet Activities Board (IAB) - Network Management System

Need for an automated management tool for TCP/IP network and Internet

Standards required to allow multi-vendor networks

View the entire network as a unified architecture

Single operator interface

Powerful, user friendly command set
SNMP - RFC 1067 - August 1988
»
J. Case
»
M. Fedor
»
M. Schoffstall
»
J. Davin
What is SNMP?



Network management software for networks operating TCP/IP model

Application Layer TCP/IP - OSI

Variety of Operating Systems
SNMP network management - 4 key elements

Management Station

Management Agent

Management Information Base

Network Management Protocol
Simple Network Management Protocol version 1 (SNMPv1)
- Protocol that enables a management station to configure, monitor network devices

Simple Network Management Protocol version 2 (SNMPv2)
- Update provides additional administrative structure, authentication, and privacy
- SNMPv1 and SNMPv2 are incompatible

Simple Network Management Protocol version 3 (SNMPv3)
- Update provides additional security and administrative capabilities
Management Station
 Standalone device or part of a shared system
 Interface for human network manager
 Has management applications
 Interface to monitor and control network
Management Agent
 Platforms, such as hosts, bridges, routers, and hubs
 Equipped with agent software so they can be managed
 Responds to requests for information
 Responds to requests for action
 Asynchronously supply important but unsolicited information
Management Information Base (MIB)
 Representation of network resources as objects
 Each object is a data variable that represents one aspect of managed agent

Standardized across system
 Collection of objects is referred to as a MIB

Collection of access points for the management station
 Management station

Retrieves values of MIB objects to provide monitoring

Sets MIB object values to change configuration
Network Management Protocol
 Link between management station and agent

TCP/IP uses SNMP

SNMPv2 for OSI & TCP/IP
 Key capabilities

get - management station retrieves value

set - management station sets value

notify - agent sends event notification
How does SNMP work?
 Network management software

Controls devices connected to a network

Manages performance, solves problems, optimizes network

Firewall
 Community

Devices store information about the community

Command input limited to certain machines

MIB contains communication information

Protocols

Device identifications
SNMP Architecture
 Application-level protocol of the TCP/IP model
 Operates on top of UDP
 Typical configuration:


Standalone management station

Manager process controls access to a central MIB

Provides an interface to the network manager
SNMP, UDP, IP and network dependent protocol (Ethernet, ATM)

Each agent must be implemented same way
SNMP Architecture
 Closer look:

Management station issues 3 messages

All 3 are acknowledged by the agent

May issue a trap message - something undesirable happens
 Relies on UDP - connectionless protocol

No ongoing connections are maintained

Each exchange is a separate transaction
Bibliography
Pictures:
Stallings, William. Data and Computer Communications. 8th ed. New Jersey: Pearson
Prentice Hall, 2007. 760-771.
Information:
Stallings, William. Data and Computer Communications. 8th ed. New Jersey: Pearson
Prentice Hall, 2007. 760-771.
"Cisco Documentation." cisco.com. 12 Oct. 2006. Feb. 2008
<http://www.cisco.com/univercd/cc/td/doc/cisintwk/ito_doc/snmp.htm>.
"Simple Network Management Protocol." Wikipedia. 10 Jan. 2008. Feb. 2008
<http://en.wikipedia.org/wiki/Simple_Network_Management_Protocol#SNMP_basic_co
mponents>.
Q?A!