McGraw-Hill©The McGraw-Hill Companies, Inc., 2000 Chapter 23 Simple Network Management Protocol (SNMP)

McGraw-Hill©The McGraw-Hill Companies, Inc., 2000 CONTENTS CONCEPT MANAGEMENT COMPONENTS SMI MIB SNMP MESSAGES UDP PORTS SECURITY

McGraw-Hill©The McGraw-Hill Companies, Inc., 2000 CONCEPT 23.1

McGraw-Hill©The McGraw-Hill Companies, Inc., 2000 Figure 23-1 Concept

McGraw-Hill©The McGraw-Hill Companies, Inc., 2000 MANAGEMENT COMPONENTS 23.2

McGraw-Hill©The McGraw-Hill Companies, Inc., 2000 Figure 23-2 Components of network management on the Internet

McGraw-Hill©The McGraw-Hill Companies, Inc., 2000 SNMP defines the format of packets exchanged between a manager and an agent. It reads and changes the status (values) of objects (variables) in SNMP packets.

McGraw-Hill©The McGraw-Hill Companies, Inc., 2000 SMI defines the general rules for naming objects, defining object types (including range and length), and showing how to encode objects and values.

McGraw-Hill©The McGraw-Hill Companies, Inc., 2000 SMI defines neither the number of objects an entity should manage, nor names the objects to be managed nor defines the association between the objects and their values.

McGraw-Hill©The McGraw-Hill Companies, Inc., 2000 MIB creates a collection of named objects, their types, and their relationships to each other in an entity to be managed.

McGraw-Hill©The McGraw-Hill Companies, Inc., 2000 We can compare the task of network management to the task of writing a program. 1. Both tasks need rules. In network management this is handled by SMI. 2. Both tasks need variable declarations. In network management this is handled by MIB. 3. Both tasks have actions performed by statements.In network management this is handled by SNMP.

McGraw-Hill©The McGraw-Hill Companies, Inc., 2000 SMI 23.3

McGraw-Hill©The McGraw-Hill Companies, Inc., 2000 Figure 23-3 Object attributes

McGraw-Hill©The McGraw-Hill Companies, Inc., 2000 Figure 23-4 Object identifier

McGraw-Hill©The McGraw-Hill Companies, Inc., 2000 All objects managed by SNMP are given an object identifier. The object identifier always starts with

McGraw-Hill©The McGraw-Hill Companies, Inc., 2000 Figure 23-5 Data types

McGraw-Hill©The McGraw-Hill Companies, Inc., 2000 Figure 23-6 Conceptual data types

McGraw-Hill©The McGraw-Hill Companies, Inc., 2000 Figure 23-7 Encoding format

McGraw-Hill©The McGraw-Hill Companies, Inc., 2000 Figure 23-8 Length format

McGraw-Hill©The McGraw-Hill Companies, Inc., 2000 Figure 23-9 Example 1: INTEGER 14

McGraw-Hill©The McGraw-Hill Companies, Inc., 2000 Figure Example 2: OCTET STRING “HI”

McGraw-Hill©The McGraw-Hill Companies, Inc., 2000 Figure Example 3: ObjectIdentifier

McGraw-Hill©The McGraw-Hill Companies, Inc., 2000 Figure Example 4: IPAddress

McGraw-Hill©The McGraw-Hill Companies, Inc., 2000 MIB 23.4

McGraw-Hill©The McGraw-Hill Companies, Inc., 2000 Figure mib-2

McGraw-Hill©The McGraw-Hill Companies, Inc., 2000 Figure udp group

McGraw-Hill©The McGraw-Hill Companies, Inc., 2000 Figure udp variables and tables

McGraw-Hill©The McGraw-Hill Companies, Inc., 2000 Figure Indexes for udpTable

McGraw-Hill©The McGraw-Hill Companies, Inc., 2000 Figure Lexicographic ordering

McGraw-Hill©The McGraw-Hill Companies, Inc., 2000 SNMP 23.5

McGraw-Hill©The McGraw-Hill Companies, Inc., 2000 Figure SNMP PDUs

McGraw-Hill©The McGraw-Hill Companies, Inc., 2000 Figure SNMP PDU format

McGraw-Hill©The McGraw-Hill Companies, Inc., 2000 MESSAGES 23.6

McGraw-Hill©The McGraw-Hill Companies, Inc., 2000 Figure SNMP message

McGraw-Hill©The McGraw-Hill Companies, Inc., 2000 Figure GetRequest message

McGraw-Hill©The McGraw-Hill Companies, Inc., 2000 UDP PORTS 23.7

McGraw-Hill©The McGraw-Hill Companies, Inc., 2000 Figure Port numbers for SNMP

McGraw-Hill©The McGraw-Hill Companies, Inc., SECURITY