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3.8. OSPF Interface Metrics

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3.8. OSPF Interface Metrics

3.8. OSPF Interface Metrics

--  OSPF Interface Metric Table

--      The Metric Table describes the metrics to be advertised
--      for a specified interface at the various types of service.
--      As such, this table is an adjunct of the OSPF Interface
--      Table.

-- Types of service, as defined by RFC 791, have the ability
-- to request low delay, high bandwidth, or reliable linkage.

-- For the purposes of this specification, the measure of
-- bandwidth

--      Metric = 10^8 / ifSpeed

-- is the default value.  For multiple link interfaces, note
-- that ifSpeed is the sum of the individual link speeds.
-- This yields a number having the following typical values:

--      Network Type/bit rate   Metric

--      >= 100 MBPS                 1
--      Ethernet/802.3             10
--      E1                         48
--      T1 (ESF)                   65
--       64 KBPS                 1562
--       56 KBPS                 1785
--       19.2 KBPS               5208
--        9.6 KBPS              10416

-- Routes that are not specified use the default (TOS 0) metric

    ospfIfMetricTable OBJECT-TYPE
        SYNTAX   SEQUENCE OF OspfIfMetricEntry
        MAX-ACCESS   not-accessible
        STATUS   current
        DESCRIPTION
           "The TOS metrics for  a  non-virtual  interface
           identified by the interface index."
       REFERENCE
          "OSPF Version 2, Appendix C.3  Router  interface
          parameters"
      ::= { ospf 8 }

    ospfIfMetricEntry OBJECT-TYPE
        SYNTAX   OspfIfMetricEntry
        MAX-ACCESS   not-accessible
        STATUS   current
        DESCRIPTION
           "A particular TOS metric for a non-virtual  in-
           terface identified by the interface index."
       REFERENCE
          "OSPF Version 2, Appendix C.3  Router  interface
          parameters"
      INDEX { ospfIfMetricIpAddress,
  ospfIfMetricAddressLessIf,
  ospfIfMetricTOS }
      ::= { ospfIfMetricTable 1 }

OspfIfMetricEntry ::=
    SEQUENCE {
        ospfIfMetricIpAddress
            IpAddress,
        ospfIfMetricAddressLessIf
            Integer32,
        ospfIfMetricTOS
            TOSType,
        ospfIfMetricValue
            Metric,
        ospfIfMetricStatus
            RowStatus
              }

    ospfIfMetricIpAddress OBJECT-TYPE
        SYNTAX   IpAddress
        MAX-ACCESS   read-only
        STATUS   current
        DESCRIPTION
           "The IP address of this OSPF interface.  On row
           creation,  this  can  be  derived  from the in-
           stance."
       ::= { ospfIfMetricEntry 1 }

    ospfIfMetricAddressLessIf OBJECT-TYPE
        SYNTAX   Integer32
        MAX-ACCESS   read-only
        STATUS   current
        DESCRIPTION
           "For the purpose of easing  the  instancing  of
           addressed   and  addressless  interfaces;  This
           variable takes the value 0 on  interfaces  with
           IP  Addresses, and the value of ifIndex for in-
           terfaces having no IP Address.   On  row  crea-
           tion, this can be derived from the instance."
       ::= { ospfIfMetricEntry 2 }


    ospfIfMetricTOS OBJECT-TYPE
        SYNTAX   TOSType
        MAX-ACCESS   read-only
        STATUS   current
        DESCRIPTION
           "The type of service metric  being  referenced.
           On  row  creation, this can be derived from the
           instance."
       ::= { ospfIfMetricEntry 3 }


    ospfIfMetricValue OBJECT-TYPE
        SYNTAX   Metric
        MAX-ACCESS   read-create
        STATUS   current
        DESCRIPTION
           "The metric of using this type  of  service  on
           this interface.  The default value of the TOS 0
           Metric is 10^8 / ifSpeed."
       ::= { ospfIfMetricEntry 4 }

    ospfIfMetricStatus OBJECT-TYPE
        SYNTAX   RowStatus
        MAX-ACCESS   read-create
        STATUS   current
        DESCRIPTION
           "This variable displays the status of  the  en-
           try.  Setting it to 'invalid' has the effect of
           rendering it inoperative.  The internal  effect
           (row removal) is implementation dependent."
       ::= { ospfIfMetricEntry 5 }



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3.8. OSPF Interface Metrics