3.8. OSPF Interface Metrics (original) (raw)

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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