Introduction to Internet Network Management

1
Introduction to Internet Network Management

• J. Won-Ki Hong
• Dept. of Computer Science and Engineering
• POSTECH
• Tel [phone]
• Email jwkhong_at_postech.ac.kr

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Table of Contents

• Background
• Origins of Internet
• Origins of Internet Network Management
• Evolution of SNMP
• SNMP Standards and RFCs
• SNMP Basic Concepts
• Network Management Architecture
• SNMP Protocol Architecture
• Proxies

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Internet Network Management

• Also referred to as SNMP-based Network Management
• Simple Network Management Protocol (SNMP) is
  often referred to as the Internet Network
  Management Framework which includes
• management architecture
• structure of management information
• management protocol
• plus related concepts...
• Most widely used in computer communication
  networks
• Internet Engineering Task Force (IETF) is
  responsible for SNMP standardization

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Origins of Internet

• ARPANET (formed by US DoD, 1969) connecting four
  geographically separated computers in US
• 23 computers in ARPANET (1971)
• Computers in UK and Norway were connected (1973)
• TCP/IP protocol suite as ARPANETs standard
  protocol (late 70s)
• TCP/IP as NFSNETs standard protocol (1984)
• Continued growth throughout the 80s and 90s
• currently more than 40,000,000 nodes on the
  Internet
• Need for the management of rapidly growing
  Internet!

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Origins of Internet NM

• Internet Control Message Protocol (ICMP)
• until late 70s, e.g., Ping utility
• Simple Gateway Monitoring Protocol (SGMP) - 1987
• High-level Entity Management System (HEMS)
• generalized version of Host Monitoring Protocol
  (HMP)
• SNMP
• enhanced version of SGMP
• an interim solution
• CMIP over TCP/IP (CMOT)
• long-term solution
• did not go very far

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Evolution of SNMP

• SNMPv1
• draft came out in 1988 and became full Internet
  standard in 1990
• most workstations, bridges, routers, switches and
  hubs are now equipped with SNMP agent
• many resource MIBs (including systems
  applications) have been defined
• RMON (1995)
• Remote Monitoring, extends the SNMPv1 MIB and
  functions
• SNMPv2
• attempted to improve the deficiencies of SNMPv1
• Full Internet Standard
• SNMPv3
• internet drafts came out in Feb. 1998, adding
  security features
• now a full Internet Standard

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IETF Standardization Process (RFC2026)http//www.
ietf.org/rfc/rfc2026.txt

• IETF forms a working group (WG) for a specific
  task
• WG generates one or more internet drafts (ID)
• ID document can follow one of three tracks
• (1) standards track, (2) informational, (3)
  experimental
• Internet documents are published as RFCs
• Internet Proposed Standard
• Internet Draft Standard
• Internet Full Standard
• Other status
• Obsolete a document that is replaced by an
  updated version
• Historic a document that is retired
• The latest status on IETF NM RFCs can be found
  from http//wwwsnmp.cs.utwente.nl/ietf/rfcs/rfcbys
  tatus.html

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SNMP Protocol RFCs
Description
Published
RFC
Status
SNMPv1 Protocol
Aug. 1988
1067
Obsoleted by 1098
SNMPv1 Protocol (republished)
Apr. 1989
1098
Obsoleted by 1157
SNMPv1 Protocol (republished)
May 1990
1157
Historic
Secure SNMP Protocol
July 1992
1352
Historic
SNMPv2 Protocol Operations
May 1993
1448
Obsoleted by 1905
SNMPv2 Transport Mappings
May 1993
1449
Obsoleted by 1906
SNMPv2 Protocol Operations
Jan. 1996
1905
Draft Standard
(updated)
SNMPv2 Transport Mappings
Jan. 1996
1906
Draft Standard
(updated)
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SNMPv1 Standards
Description
Published
RFC
Status
Structure of Identification
of Management
May 1990
1155
Full Standard
Information for TCP/IP-
based Internets (SMI)
Concise MIB Definitions
Mar. 1991
1212
Full Standard
Management Information
Base for Network
Mar. 1991
1213
Full Standard
Management of TCP/IP-
based Internet MIB-II
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SNMP Full Standards
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SNMP NM Architecture

• The manager resides in Network Management Station
  (NMS) while the agent resides in the managed
  Network Node
• The manager requests the agent to perform Set and
  Get operations on the variables in the Management
  information Base (MIB)
• By means of traps the agent occasionally notifies
  the manager about some events related to network
  operation

NMS
MIB Specification
Manager
SNMP
SNMP
Agent
Agent
Networked Node
Networked Node
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SNMP Protocol Architecture
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The Role of SNMP
SNMP NMS
SNMP agent
Management resources
Management application
SNMP managed objects
Application manages objects
GetNextRequest
GetNextRequest
GetRequest
SetRequest
GetResponse
GetRequest
SetRequest
GetResponse
Trap
Trap
SNMP manager
SNMP agent
SNMP messages
UDP
UDP
IP
IP
Network-dependent protocols
Network-dependent protocols
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SNMP Proxy Agent
Proxy agent
Management station
Proxied device
Mapping function
Management process
Manager process
Agent process
SNMP
SNMP
Protocol architecture used by proxied device
Protocol architecture used by proxied device
UDP
UDP
IP
IP
Network-dependent protocols
Network-dependent protocols
Network-dependent protocols
Network-dependent protocols
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Reading and Browsing

• Visit and browse
• IETF Web site
• www.ietf.org
• U. of Twente NM Web site
• wwwsnmp.cs.utwente.nl/ietf/rfcs/rfcbystatus.html