SNMP Management Information - PowerPoint PPT Presentation

snmp management information n.
Download
Skip this Video
Loading SlideShow in 5 Seconds..
SNMP Management Information PowerPoint Presentation
Download Presentation
SNMP Management Information

play fullscreen
1 / 10
SNMP Management Information
96 Views
Download Presentation
fineen
Download Presentation

SNMP Management Information

- - - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

  1. SNMP ManagementInformation Mi-Jung Choi Dept. of Computer Science KNU Email: mjchoi@kangwon.ac.kr

  2. Table of Contents • Structure of Management Information • Overview • Meanings of MIB • SNMP MIB Structure • MIB Object Syntax • Defining MIB Objects • Defining MIB Tables

  3. Overview of SNMP SMI • Structure of Management Information (SMI) • RFC 1155 (Full Standard) • defines the general framework for defining SNMP MIBs • describes how the managed objects (MOs) can be defined in the MIB, data types and values MOs can have and how MOs are named • SNMP SMI uses a subset of ASN.1 • SNMP MIB can store only simple data types • scalars • 2-dimensional arrays of scalars

  4. Meanings of MIB • a MIB- a single MO definition • the MIB- the union of all MO definitions • MIB- the actual values of management information in a system a system's MIB MIB document 1 2 3 the MIB MIB module a MIB a document containing definitions of management information management information a module written in a computer parsable form containing definitions a managed system

  5. MIB Structure • all MOs are structured hierarchically • Leaf objects in the tree are real MOs • Each MO has an OBJECT IDENTIFIER (OID) root ccitt(0) iso(1) joint-iso-ccitt(2) org(3) dod(6) internet(1) mgmt(2) experimental(3) snmpv2(6) private(4) mib-2(1) enterprises(1)

  6. Object Identifier (OID) • uniquely identifies an MO in the MIB internet OBJECT IDENTIFIER : = { iso(1) org(3) dod(6) 1} • can be written as { 1 3 6 1 } or 1.3.6.1 • OID for tcpConnTable is 1.3.6.1.2.1.6.13 iso org dod internet mgmt mib-2 tcp tcpConnTable 1 3 6 1 2 1 6 13 • What is the OID for the object ifInOctets? (Hint: see MIB-II interfaces group, Fig 5.1 & 6.2)

  7. Managed Object Syntax • ASN.1 notation is used to define MOs and the entire MIB structure • Universal Types • INTEGER • OCTET STRING • NULL • OBJECT IDENTIFIER • SEQUENCE • SEQUENCE-OF • Application-wide Types • Networkaddress • Ipaddress • Counter • Gauge • Timeticks • Opaque

  8. Defining Managed Objects • the macro definition used for SNMP MIBs was initially defined in RFC 1155 (SMI) and later expanded in RFC 1212 (Concise MIB Definition) • RFC 1155 is used for defining MOs in MIB-I • RFC 1212 is used for defining MOs in MIB-II which is implemented in most SNMP agents today • OBJECT TYPE MACRO definition is used to define MOs • see Figure 5.3 (Macro for Managed Objects - RFC 1212) • see Figure 5.4 (SMI - RFC 1155)

  9. Defining MO Tables • SNMP MIB structure is a simple 2-dimensional table with scalar-valued entries • A table typically consists of a SEQUENCE OF some entries • A table entry typically consists of a SEQUENCE that includes a number of scalar elements • See Figure 5.6 (MIB-II Specification of TCP Connection Table - RFC 1213)

  10. Encoding MOs • Objects in the MIB are encoded using the basic encoding rules (BER) • BER is a widely used and standard encoding scheme • READING – Read Chapter 5