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            RowStatus                                FROM SNMPv2-TC
            intSrv                        FROM INTEGRATED-SERVICES-MIB
            ifIndex                                  FROM IF-MIB;

--  This MIB module uses the extended OBJECT-TYPE macro as
--  defined in [9].

intSrvGuaranteed MODULE-IDENTITY
        LAST-UPDATED "9511030500Z" -- Thu Aug 28 09:04:22 PDT 1997
        ORGANIZATION "IETF Integrated Services Working Group"
       "       Fred Baker
       Postal: Cisco Systems
               519 Lado Drive
               Santa Barbara, California 93111
       Tel:    +1 805 681 0115
       "The MIB module to describe the Guaranteed Service of
       the Integrated Services Protocol"
    ::= { intSrv 5 }

intSrvGuaranteedObjects          OBJECT IDENTIFIER
                                 ::= { intSrvGuaranteed 1 }
intSrvGuaranteedNotifications    OBJECT IDENTIFIER
                                 ::= { intSrvGuaranteed 2 }
intSrvGuaranteedConformance      OBJECT IDENTIFIER
                                 ::= { intSrvGuaranteed 3 }

--      The Integrated Services Interface Attributes Database
--      contains information that is shared with other reservation
--      procedures such as ST-II.

    intSrvGuaranteedIfTable OBJECT-TYPE
        SYNTAX      SEQUENCE OF IntSrvGuaranteedIfEntry
        MAX-ACCESS  not-accessible
        STATUS      current
           "The attributes of the system's interfaces  ex-
           ported by the Guaranteed Service."
       ::= { intSrvGuaranteedObjects 1 }

    intSrvGuaranteedIfEntry OBJECT-TYPE
        SYNTAX      IntSrvGuaranteedIfEntry
        MAX-ACCESS  not-accessible
        STATUS      current
           "The reservable attributes of  a  given  inter-
       INDEX { ifIndex }
       ::= { intSrvGuaranteedIfTable 1 }

IntSrvGuaranteedIfEntry ::=
        intSrvGuaranteedIfBacklog INTEGER,
        intSrvGuaranteedIfDelay   INTEGER,
        intSrvGuaranteedIfSlack   INTEGER,
        intSrvGuaranteedIfStatus  RowStatus

    intSrvGuaranteedIfBacklog OBJECT-TYPE
        SYNTAX      INTEGER (0..'0FFFFFFF'h)
        UNITS       "bytes"
        MAX-ACCESS  read-create
        STATUS      current
           "The Backlog  parameter  is  the  data  backlog
           resulting  from  the vagaries of how a specific
           implementation deviates from a  strict  bit-by-
           bit  service.  So, for instance, for packetized
           weighted fair queueing, Backlog is set  to  the
           Maximum Packet Size.

           The Backlog term is measured in units of bytes.
           An  individual  element can advertise a Backlog
           value between 1 and 2**28 (a  little  over  250
           megabytes)  and  the  total added over all ele-
           ments can range as high as  (2**32)-1.   Should
           the  sum of the different elements delay exceed
           (2**32)-1, the end-to-end error term should  be
       ::= { intSrvGuaranteedIfEntry 1 }

    intSrvGuaranteedIfDelay OBJECT-TYPE
        SYNTAX      INTEGER (0..'0FFFFFFF'h)
        UNITS       "microseconds"
        MAX-ACCESS  read-create
        STATUS      current
           "The Delay parameter at  each  service  element
           should  be  set  to the maximum packet transfer
           delay (independent of bucket size) through  the
           service  element.   For  instance,  in a simple
           router, one might compute the worst case amount
           of  time  it  make  take  for a datagram to get
           through the input interface to  the  processor,
           and how long it would take to get from the pro-
           cessor to the outbound interface (assuming  the
           queueing  schemes work correctly).  For an Eth-
           ernet, it might represent the worst case  delay
           if  the maximum number of collisions is experi-

           The Delay term is measured in units of one  mi-
           crosecond.  An individual element can advertise
           a delay value between  1  and  2**28  (somewhat
           over two minutes) and the total delay added all
           elements  can  range  as  high  as   (2**32)-1.
           Should  the sum of the different elements delay
           exceed (2**32)-1, the end-to-end  delay  should
           be (2**32)-1."
       ::= { intSrvGuaranteedIfEntry 2 }

    intSrvGuaranteedIfSlack OBJECT-TYPE
        SYNTAX      INTEGER (0..'0FFFFFFF'h)
        MAX-ACCESS  read-create
        STATUS      current
           "If a network element uses a certain amount  of
           slack,  Si,  to  reduce the amount of resources
           that it has reserved for a particular flow,  i,
           the  value  Si  should be stored at the network
           element.   Subsequently,  if  reservation   re-
           freshes  are  received  for flow i, the network
           element must use the same slack Si without  any
           further computation. This guarantees consisten-
           cy in the reservation process.

           As an example for the use of  the  slack  term,
           consider the case where the required end-to-end
           delay, Dreq, is larger than the  maximum  delay
           of the fluid flow system.  In this, Ctot is the
           sum of the Backlog terms end to end,  and  Dtot
           is the sum of the delay terms end to end.  Dreq
           is obtained by setting R=r in the  fluid  delay
           formula, and is given by

                        b/r + Ctot/r + Dtot.

           In this case the slack term is

                  S = Dreq - (b/r + Ctot/r + Dtot).

           The slack term may be used by the network  ele-
           ments  to  adjust  their local reservations, so
           that they can admit flows that would  otherwise
           have been rejected. A service element at an in-
           termediate network element that can  internally
           differentiate between delay and rate guarantees
           can now take advantage of this  information  to
           lower the amount of resources allocated to this
           flow. For example, by taking an amount of slack
           s  <= S, an RCSD scheduler [5] can increase the
           local delay bound, d, assigned to the flow,  to
           d+s. Given an RSpec, (Rin, Sin), it would do so
           by setting Rout = Rin and Sout = Sin - s.

           Similarly,  a  network  element  using  a   WFQ
           scheduler  can  decrease  its local reservation
           from Rin to Rout by using some of the slack  in
           the  RSpec.  This  can be accomplished by using
           the transformation rules given in the  previous
           section,  that ensure that the reduced reserva-
           tion level will not increase the  overall  end-
           to-end delay."
       ::= { intSrvGuaranteedIfEntry 3 }

    intSrvGuaranteedIfStatus OBJECT-TYPE
        SYNTAX      RowStatus
        MAX-ACCESS  read-create
        STATUS      current
           "'valid' on interfaces that are configured  for
           the Guaranteed Service."
       ::= { intSrvGuaranteedIfEntry 4 }

--      No notifications are currently defined

-- conformance information
intSrvGuaranteedGroups      OBJECT IDENTIFIER
                            ::= { intSrvGuaranteedConformance 1 }
intSrvGuaranteedCompliances OBJECT IDENTIFIER
                            ::= { intSrvGuaranteedConformance 2 }

-- compliance statements

    intSrvGuaranteedCompliance MODULE-COMPLIANCE
        STATUS  current
           "The compliance statement "
       MODULE  -- this module
       ::= { intSrvGuaranteedCompliances 1 }

    intSrvGuaranteedIfAttribGroup OBJECT-GROUP
         OBJECTS {
        STATUS  current
           "These objects are required  for  Systems  sup-
           porting the Guaranteed Service of the Integrat-
           ed Services Architecture."
       ::= { intSrvGuaranteedGroups 2 }