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

3
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

6
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 )

7
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)

8
MIB Naming Format

• Uses ISO format
• Example
• Ciscos 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

9
SNMP Protocol Operation

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

10
SNMP Message Format
11
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

12
Johns Theory on Network Management

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