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POSTECH DP&NM Lab
Introduction to Internet
Network Management
J. Won-Ki Hong
Dept. of Computer Science and Engineering
POSTECH
Tel: 054-279-2244
Email: [email protected]
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POSTECH DP&NM Lab
Table of Contents
• Background
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–
–
–
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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POSTECH DP&NM Lab
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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POSTECH DP&NM Lab
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 ARPANET’s standard protocol
(late 70’s)
• TCP/IP as NFSNET’s standard protocol (1984)
• Continued growth throughout the 80’s and 90’s
– currently more than 40,000,000 nodes on the Internet
• Need for the management of rapidly growing Internet!
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POSTECH DP&NM Lab
Origins of Internet NM
• Internet Control Message Protocol (ICMP)
– until late 70’s, 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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POSTECH DP&NM Lab
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/rfcbystatus.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
(updated)
SNMPv2 Transport Mappings
(updated)
Jan. 1996
1905
Draft Standard
Jan. 1996
1906
Draft Standard
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POSTECH DP&NM Lab
SNMPv1 Standards
Description
Structure of Identification
of Management
Information for TCP/IPbased Internets (SMI)
Concise MIB Definitions
Management Information
Base for Network
Management of TCP/IPbased Internet: MIB-II
Published RFC
Status
May 1990 1155
Full Standard
Mar. 1991
1212
Full Standard
Mar. 1991
1213
Full Standard
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SNMP Full Standards
RFC
Title
3418
Management Information Base (MIB) for the Simple Network Management Protocol (SNMP)
3417
Transport Mappings for the Simple Network Management Protocol (SNMP)
3416
Version 2 of the Protocol Operations for the Simple Network Management Protocol (SNMP)
3415
View-based Access Control Model (VACM) for the Simple Network Management Protocol (SNMP)
3414
User-based Security Model (USM) for version 3 of the Simple Network Management Protocol (SNMPv3)
3413
Simple Network Management Protocol (SNMP) Applications
3412
Message Processing and Dispatching for the Simple Network Management Protocol (SNMP)
3411
An Architecture for Describing Simple Network Management Protocol (SNMP) Management Frameworks
2819
Remote Network Monitoring Management Information Base
2580
Conformance Statements for SMIv2
2579
Textual Conventions for SMIv2
2578
Structure of Management Information Version 2 (SMIv2)
1643
Definitions of Managed Objects for the Ethernet-like Interface Types
1213
Management Information Base for Network Management of TCP/IP-based internets:MIB-II
1212
Concise MIB definitions
1155
Structure and identification of management information for TCP/IP-based internets
1065
Structure and identification of management information for TCP/IP-based internets
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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
MIB
Networked Node
Agent
MIB
Networked Node
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SNMP Protocol Architecture
Network
Admin
NMS
Host
Manager process
Agent process User processes
SNMP
Central
MIB
UDP
SNMP
FTP, etc
UDP
TCP
IP
IP
Network-dependent
protocols
Network-dependent protocols
Host
Agent process
Router
Agent process
User processes
SNMP
FTP, etc
UDP
TCP
IP
Network-dependent protocols
Internetwork
SNMP
UDP
IP
Network-dependent
protocols
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The Role of SNMP
SNMP NMS
SNMP agent
Management resources
Management application
SNMP managed objects
SNMP manager
UDP
SetRequest
SetRequest
Application
manages objects
SNMP messages
IP
SNMP agent
UDP
IP
Network-dependent protocols
Network-dependent protocols
network or
internet
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SNMP Proxy Agent
Proxy agent
Management station
Manager process
SNMP
Mapping function
UDP
UDP
IP
IP
Network-dependent
protocols
Management
process
Agent process
SNMP
Proxied device
Protocol
architecture used
by proxied device
Network-dependentNetwork-dependent
protocols
protocols
Protocol
architecture used
by proxied device
Network-dependent
protocols
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POSTECH DP&NM Lab
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
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