Network Management

1
Network Management
Computer Networks
2
OSI Network Management Model

• Performance Management
• e.g. utilization
• Fault Management
• e.g. SNMP traps
• Configuration Management
• e.g. configuration files
• Accounting Management
• e.g. chargeback systems
• Security Management
• e.g. access control

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Components of a Network Management System

• Manager
• centralized
• collects, controls, and reports
• Managed entities
• agent software
• management information base (MIB)
• Network management protocol

4
Simple Network Management Protocol

• Most popular version is SNMPv1
• SNMPv2 exists, but no one uses it
• SNMPv3 enhances admin and security
• SNMPv1 defined in RFC 1157
• Two popular books
• The Simple Book - M. Rose
• SNMP, SNMPv2, SNMPv3 and RMON 1 and 2 - W.
  Stallings

5
Structure of Management Information (SMI)

• Based on ASN.1
• Defines information in managed entity
• Integer32, Unsigned32
• IPaddress
• Counter32, Counter64
• High level constructs

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SMI Example

• ipInDelivers ObjectType
• SYNTAX Counter32
• MAX-ACCESS read-only
• STATUS current
• DESCRIPTION
• "The total number of input datagrams successfully
  delivered to IP user-protocols (including ICMP).?
• ( ip 9 )

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Management Information Base (MIB)

• Stores information of managed entity
• Values can be queried and often set using the
  network management protocol (SNMP)
• Many standard MIBs and many more private MIBs
• Objects arranged in MIB according to its Object
  ID (OID)

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MIB Naming Format

• Uses ISO format
• Example
• Cisco?s MIB
• 1.3.6.1.4.1.9
• A Cisco MIB object
• 1.3.6.1.4.1.9.9.13.1.3.1.3
• device temperature

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SNMP Protocol Operation

• GetRequest
• GetNextRequest
• SetRequest
• GetResponse
• Trap
• SNMPv2 adds functionality
• e.g. GetBulkRequest

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SNMP Message Format
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Remote Network Monitoring (RMON)

• RMON is a MIB for remote management of a network
  as opposed to a single managed entity
• Probes collect and process information
• Standard RMON groups
• statistics, history, alarm, host, hostTopN,
  matrix, filter, packet capture, event

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John?s Theory on Network Management

• If you spend more time managing your network
  management system(s) than your actual production
  network, you?re doing something very wrong.