Management information base
From Wikipedia, the free encyclopedia
A management information base (MIB) stems from the OSI/ISO Network management model and is a type of database used to manage the devices in a communications network. It comprises a collection of objects in a (virtual) database used to manage entities (such as routers and switches) in a network.
Objects in the MIB are defined using a subset of Abstract Syntax Notation One (ASN.1) called "Structure of Management Information Version 2 (SMIv2)" RFC 2578.The software that performs the parsing is a MIB compiler.
The database is hierarchical (tree-structured) and entries are addressed through object identifiers. Internet documentation RFCs discuss MIBs, notably RFC 1155, "Structure and Identification of Management Information for TCP/IP based internets", and its two companions, RFC 1213, "Management Information Base for Network Management of TCP/IP-based internets", and RFC 1157, "A Simple Network Management Protocol".
SNMP, a communication protocol between management stations, such as consoles, and managed objects (MIB objects), such as routers, gateways, and switches, makes use of MIBs. Components controlled by the management console need a so-called SNMP agent — a software module that can communicate with the SNMP manager.
SNMP uses a specified set of commands and queries. A MIB should contain information on these commands and on the target objects (controllable entities or potential sources of status information) with a view to tuning the network transport to the current needs.
Examples of MIB objects include:
- output queue length, which has the name ifOutQLen
- Address Translation table (like ARP tables) called atTable.
RFC 1213 defines these as mandatory: if an environment does not use the atTable (as in the case of DDN-X.25 units) then the atTable simply remains empty. The table object includes, of course, definitions of table entries, atEntry and information about interfaces (if) for each atEntry, etc.
MIBs are periodically updated to add new functionality, remove ambiguities and to fix defects. These changes are made in conformance to section 10 of RFC 2578. An example of an MIB that has been updated many times is the important set of objects that was originally defined in RFC 1213 "MIB-II". This MIB has since been split up and can be found in MIBs such as RFC 4293 "Management Information Base for the Internet Protocol (IP)", RFC 4022 "Management Information Base for the Transmission Control Protocol (TCP)", RFC 4113 "Management Information Base for the User Datagram Protocol (UDP)", RFC 2863 "The Interfaces Group MIB" and RFC 3418 "Management Information Base (MIB) for the Simple Network Management Protocol (SNMP)".
[edit] MIBs index
There are a large number of MIBs defined by both standards organizations like the IETF, private enterprises and other entities. There are 318 RFCs in the first 5000 RFCs from the IETF that contain MIBs. This list is merely a fraction of the MIBs that have been written:
- SNMP - SMI:RFC 1155 - Defines the Structure of Management Information (SMI)
- MIB-I: RFC 1156 - Historically used with CMOT , not to be used with SNMP
- SNMPv2-SMI: RFC 2578 - Structure of Management Information Version 2 (SMIv2)
- MIB-II: RFC 1213 - Management Information Base for Network Management of TCP/IP-based internets
- SNMPv2-MIB: RFC 3418 - Management Information Base (MIB) for the Simple Network Management Protocol (SNMP)
- TCP-MIB: RFC 4022 - Management Information Base for the Transmission Control Protocol (TCP)
- UDP-MIB: RFC 4113 - Management Information Base for the User Datagram Protocol (UDP)
- IP-MIB: RFC 4293 - Management Information Base for the Internet Protocol (IP)
- IF-MIB: RFC 2863 - The Interfaces Group MIB
- ENTITY-MIB: RFC 4133 - Entity MIB (Version 3)
- ENTITY-STATE-MIB: RFC 4268 - Entity State MIB
- ALARM-MIB: RFC 3877 - Alarm Management Information Base (MIB)
- Fibre Channel
- FC-MGMT-MIB: RFC 4044 Fibre Channel Management MIB
- FIBRE-CHANNEL-FE-MIB: RFC 2837 Definitions of Managed Objects for the Fabric Element in Fibre Channel Standard
- Bridge
- P-BRIDGE-MIB: RFC 2674-1999, proposed standard, Definitions of Managed Objects for Bridges with Traffic Classes, Multicast Filtering and Virtual LAN Extensions
- SBRIDGEMIB: RFC 1525-1993, proposed standard, Definitions of Managed Objects for Source Routing Bridges
- BRIDGEMIB: RFC 1493-1993, draft standard, Definitions of Managed Objects for Bridges
- HPR-IP-MIB: RFC 2584 - Definitions of Managed Objects for APPN/HPR in IP Networks
