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RFC 3292

 
 
 

General Switch Management Protocol (GSMP) V3

Part 4 of 5, p. 73 to 100
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8.  Configuration Messages

   The configuration messages permit the controller to discover the
   capabilities of the switch.  Three configuration request messages
   have been defined: Switch, Port, and All Ports.

8.1  Switch Configuration Message

   The Switch Configuration message requests the global (non port-
   specific) configuration for the switch.  The Switch Configuration
   message is:

      Message Type = 64

   The Port field is not used in the switch configuration message.

   The Switch Configuration message has the following format:

    0                   1                   2                   3
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |    Version    | Message Type  |    Result     |     Code      |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | Partition ID  |            Transaction Identifier             |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |I|      SubMessage Number      |           Length              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |     MType     |     MType     |     MType     |     MType     |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |    Firmware Version Number    |          Window Size          |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |          Switch Type          |                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+                               +
   |                          Switch Name                          |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                          Max Reservations                     |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

      Note: Fields and Parameters that have been explained in the
         description of the general messages will not be explained in
         this section.  Please refer to section 3.1 for details.

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      MType
         Represents an alternative QoS Configuration type.  In the
         request message the requested MType is in the most significant
         (leftmost) MType byte; the other three MType bytes are unused.
         The reply message will either accept the MType request by
         including the requested MType in the leftmost MType field of
         the response message or it will reject the MType request by
         responding with MType=0, the default MType, in the first MType
         field.  Optionally, in the case of a rejection, the switch
         reply can include up to 3 additional MType values, each of
         which indicates an available alternative QoS Configuration.  A
         switch that supports only the default QoS Configuration always
         returns MType=0 in all four MType fields.  MType negotiation is
         discussed in section 8.1.1.

            0          -  Indicates use of the default GSMP model
            1-200      -  Reserved
            201-255    -  Experimental

      Firmware Version Number
         The version number of the switch control firmware installed.

      Window Size
         The maximum number of unacknowledged request messages that may
         be transmitted by the controller without the possibility of
         loss.  This field is used to prevent request messages being
         lost in the switch because of overflow in the receive buffer.
         The field is a hint to the controller.  If desired, the
         controller may experiment with higher and lower window sizes to
         determine heuristically the best window size.

      Switch Type
         A 16-bit field allocated by the manufacturer of the switch.
         (For these purposes, the manufacturer of the switch is assumed
         to be the organisation identified by the OUI in the Switch Name
         field.)  The Switch Type identifies the product.  When the
         Switch Type is combined with the OUI from the Switch Name the
         product is uniquely identified.  Network Management may use
         this identification to obtain product related information from
         a database.

      Switch Name
         A 48-bit quantity that is unique within the operational context
         of the device.  A 48-bit IEEE 802 MAC address, if available,
         may be used as the Switch Name.  The most significant 24 bits

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         of the Switch Name MUST be an Organisationally Unique
         Identifier (OUI) that identifies the manufacturer of the
         switch.

      Max Reservations
         The maximum number of Reservations that the switch can support
         (see Chapter 5).  A value of 0 indicates that the switch does
         not support Reservations.

8.1.1  Configuration Message Processing

   After adjacency between a controller and after a switch is first
   established the controller that opts to use a QoS Configuration model
   other then the default would send the Switch Configuration request
   including the requested QoS Configuration's MType value in the
   request message.  This request MUST be sent before any connection
   messages are exchanged.  If the switch can support the requested QoS
   configuration, then the switch includes the requested MType value in
   the response message as an indication that it accepts the request.
   If the switch cannot support the requested QoS Configuration, it
   replaces the MType value in the request message with that of the
   default QoS Configuration, i.e., MType=0.

   The switch configuration response messages may additionally include
   the MType values of up to three alternative QoS Configurations that
   the switch supports and that the controller may choose between.

   The exchange continues until the controller sends a requested MType
   that the switch accepts or until it sends a connection request
   message.  If the exchange ends without confirmation of an alternate
   switch model, then the default Mtype=0 is be used.

   Once an MType has been established for the switch, it cannot be
   changed without full restart, that is the re-establishment of
   adjacency with the resetting of all connections.

8.2  Port Configuration Message

   The Port Configuration message requests the switch for the
   configuration information of a single switch port.  The Port field in
   the request message specifies the port for which the configuration is
   requested.  The Port Configuration message is:

      Message Type = 65.

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   The Port Configuration success response message has the following
   format:

    0                   1                   2                   3
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |    Version    | Message Type  |    Result     |     Code      |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | Partition ID  |            Transaction Identifier             |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |I|      SubMessage Number      |           Length              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                             Port                              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                       Port Session Number                     |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                      Event Sequence Number                    |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |          Event Flags          |     Port Attribute Flags      |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |   PortType    |S|x|x|x|x|x|x|x|      Data Fields Length       |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   ~                     PortType Specific Data                    ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |x x x x x x x x x x x x x x x x|   Number of Service Specs     |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-|
   |                                                               |
   ~                      Service Specs List                       ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

      Note: Fields and Parameters that have been explained in the
         description of the general messages will not be explained in
         this section.  Please refer to section 3.1 for details.

      Port
         The switch port to which the configuration information refers.
         Configuration information relating to both the input and the
         output sides of the switch port is given.  Port numbers are 32
         bits wide and allocated by the switch.  The switch may choose
         to structure the 32 bits into subfields that have meaning to
         the physical structure of the switch hardware (e.g., physical
         slot and port).  This structure may be indicated in the
         Physical Slot Number and Physical Port Number fields.

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      Event Sequence Number
         The Event Sequence Number is set to zero when the port is
         initialised.  It is incremented by one each time the port
         detects an asynchronous event that the switch would normally
         report via an Event message.  The Event Sequence Number is
         explained in section 9.

      Event Flags
         Event Flags in a switch port corresponds to a type of Event
         message.

      Port Attribute Flags
         Port Attribute Flags indicate specific behaviour of a switch
         port.  The format of the Port Attribute Flags field is given
         below:

                0                   1
                0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6
               +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
               |R|x|x|x|x|x|x|x|x|x|x|x|x|x|x|x|x|
               +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

         R: Connection Replace flag
            If set, indicates that connections being established by an
            Add Branch message with a corresponding R-bit set will
            replace any previously established connection if a clash
            between the established output branch and the requested
            output branch occurs [see chapter 4.2].

         x: Unused.

      PortType

         1: PortType is ATM
         2: PortType is FR
         3: PortType is MPLS

      S: Service Model
         If set, indicates that Service Model data follows the
         PortSpecific port configuration data.

      Data Fields Length
         The total length in bytes of the combined PortType Specific
         Data and Service Model Data fields.  The length of each of
         these fields may be derived from the other data so the value of
         Data Fields Length serves primarily as a check and to assist
         parsing of the All Ports Configuration message success
         response.

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      PortType Specific Data
         This field contains the configuration data specific to the
         particular port type as specified by the PortType field.  The
         field format and length also depends on the value of the
         PortType.  PortType Specific Data is defined below.

      Number of Service Specs
         Field contains the total number of Service Specs following in
         the remainder of the Port Configuration message response or
         Port Configuration Record.

      Service Specs List
         The Service Specs correspond to the Input and Output Service
         selectors used in Connection Management and Reservation
         messages.  Specifically they define the possible values used
         when the Service Selector (IQS or OQS) is set to 0b10
         indicating the use of the default service specification model
         defined in Chapter 10.

      Service Spec
         The format of each service spec is given below:

    0                   1                   2                   3
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |         Service ID            |       Capability Set ID       |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

         Each Service Spec identifies a Service supported by the switch
         together with the Capability Set ID that identifies the
         parameters of that instance of the Service.  The Service Spec
         List may contain more than one Service Spec sharing the same
         Service ID.  However, each Service Spec in the Service Specs
         List MUST be unique.

         Service ID
            Field contains the Service ID of a Service supported on the
            port.  Service ID values are defined as part of the Service
            definition in Chapter 9.6.

         Capability Set ID
            Field identifies a Capability Set ID of the Service
            specified by the Service ID that is supported on the port.
            Capability Set ID values are defined by the Switch in the
            Service Configuration response message (see Section 8.4).
            The switch MUST NOT return a {Service ID, Capability Set ID}
            pair that is not reported in a Service Configuration
            response message.

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8.2.1  PortType Specific Data

   The length, format and semantics of the PortType Specific Data field
   in the Port Configuration message success response and in the Port
   Records of the All Port Configuration message success response all
   depend on the PortType value of the same message or record
   respectively.  The specification of the PortType Specific Data field
   is given below.  For each defined PortType value the Min and Max
   Label fields are given in the subsequent subsections.

    0                   1                   2                   3
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |P|M|L|R|Q|  Label Range Count  |      Label Range Length       |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   ~                   Default Label Range Block                   ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                       Receive Data Rate                       |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                      Transmit Data Rate                       |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |  Port Status  |   Line Type   |  Line Status  |  Priorities   |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |     Physical Slot Number      |     Physical Port Number      |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

      Note: Fields and Parameters that have been explained in the
         description of the general messages will not be explained in
         this section.  Please refer to section 3.1 for details.

   Where each of the ranges in the Default Label Range Blocks will have
   the following format:

   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |x|x|V|C|                                                       |
   +-+-+-+-+                    Min Label                          |
   ~                                                               ~
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |x|x|x|x|                                                       |
   +-+-+-+-+                    Max Label                          |
   ~                                                               ~
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

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      Flags

         P: VP Switching
            The ATM VPC flag may only be set for ports with
            PortType=ATM.  The VP Switching flag, if set, indicates that
            this input port is capable of supporting virtual path
            switching.  Else, if zero, it indicates that this input port
            is only capable of virtual channel switching.

         M: Multicast Labels
            The Multicast Labels flag, if set, indicates that this
            output port is capable of labelling each output branch of a
            point-to-multipoint tree with a different label.  If zero,
            it indicates that this output port is not able to label each
            output branch of a point-to-multipoint tree with a different
            label.

         L: Logical Multicast
            The Logical Multicast flag, if set, indicates that this
            output port is capable of supporting more than a single
            branch from any point-to-multipoint connection.  This
            capability is often referred to as logical multicast.  If
            zero, it indicates that this output port can only support a
            single output branch from each point-to-multipoint
            connection.

         R: Label Range
            The Label Range flag, if set, indicates that this switch
            port is capable of reallocating its label range and
            therefore accepts the Label Range message.  Else, if zero,
            it indicates that this port does not accept Label Range
            messages.

         Q: QoS
            The QoS flag, if set, indicates that this switch port is
            capable of handling the Quality of Service messages defined
            in section 9 of this specification.  Else, if zero, it
            indicates that this port does not accept the Quality of
            Service messages.

         V: Label
            The Label flag is port type specific.

         C: Multipoint Capable
            This flag indicates that the label range may be used for
            multipoint connections.

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      Label Range Count
         The total number of Default Label Range elements contained in
         the Default Label Range Block.

      Label Range Length
         Byte count in the Default Label Range Block.

      Min Label
         The specification of the Min Label field for each defined
         PortType value is given in the subsequent subsections.  The
         default minimum value of a dynamically assigned incoming label
         that the connection table on the input port supports and that
         may be controlled by GSMP.  This value is not changed as a
         result of the Label Range message.

      Max Label
         The specification of the Max Label field for each defined
         PortType value is given in the subsequent subsections.  The
         default maximum value of a dynamically assigned incoming label
         that the connection table on the input port supports and that
         may be controlled by GSMP.  This value is not changed as a
         result of the Label Range message.

      Receive Data Rate

         The maximum rate of data that may arrive at the input port in;

         cells/s          for PortType = ATM
         bytes/s          for PortType = FR
         bytes/s          for PortType = MPLS

      Transmit Data Rate

         The maximum rate of data that may depart from the output port
         in;

         cells/s          for PortType = ATM
         bytes/s          for PortType = FR
         bytes/s          for PortType = MPLS

         (The transmit data rate of the output port may be changed by
         the Set Transmit Data Rate function of the Port Management
         message.)

      Port Status
         Gives the administrative state of the port.  The defined values
         of the Port Status field are:

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         Available:
            Port Status = 1.  The port is available to both send and
            receive cells or frames.  When a port changes to the
            Available state from any other administrative state, all
            dynamically assigned connections MUST be cleared and a new
            Port Session Number MUST be generated.

         Unavailable:
            Port Status = 2.  The port has intentionally been taken out
            of service.  No cells or frames will be transmitted from
            this port.  No cells or frames will be received by this
            port.

         Internal Loopback:
            Port Status = 3.  The port has intentionally been taken out
            of service and is in internal loopback: cells or frames
            arriving at the output port from the switch fabric are
            looped through to the input port to return to the switch
            fabric.  All of the functions of the input port above the
            physical layer, e.g., header translation, are performed upon
            the looped back cells or frames.

         External Loopback:
            Port Status = 4.  The port has intentionally been taken out
            of service and is in external loopback:  cells or frames
            arriving at the input port from the external communications
            link are immediately looped back to the communications link
            at the physical layer without entering the input port.  None
            of the functions of the input port above the physical layer
            are performed upon the looped back cells or frames.

         Bothway Loopback:
            Port Status = 5.  The port has intentionally been taken out
            of service and is in both internal and external loopback.

         The Port Status of the port over which the GSMP session
         controlling the switch is running MUST be declared Available.
         The controller will ignore any other Port status for this port.
         The Port Status of switch ports after power-on initialisation
         is not defined by GSMP.

      Line Type
         The type of physical transmission interface for this port.  The
         values for this field are defined by the IANAifType's specified
         in [17].

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            The following values are identified for use in this version
            of the protocol.

               PortType = Unknown: other(1)
               PortType = MPLS:    ethernetCsmacd(6),
                                   ppp(23)
               PortType = ATM:     atm(37)
               PortType = FR:      frameRelayService(44)

      Line Status
         The status of the physical transmission medium connected to the
         port.  The defined values of the Line Status field are:

            Up:
                  Line Status = 1.  The line is able to both send and
                     receive.  When the Line Status changes to Up from
                     either the Down or Test states, a new Port Session
                     Number MUST be generated.

            Down:
                  Line Status = 2.  The line is unable either to send
                     or receive or both.

            Test:
                  Line Status = 3.  The port or line is in a test
                     mode, for example, power-on test.

      Priorities
         The number of different priority levels that this output port
         can assign to connections.  Zero is invalid in this field.  If
         an output port is able to support "Q" priorities, the highest
         priority is numbered zero and the lowest priority is numbered
         "Q-1".  The ability to offer different qualities of service to
         different connections based upon their priority is assumed to
         be a property of the output port of the switch.  It may be
         assumed that for connections that share the same output port, a
         cell or frame on a connection with a higher priority is much
         more likely to exit the switch before a cell or frame on a
         connection with a lower priority if they are both in the switch
         at the same time.

      Physical Slot Number
         The physical location of the slot in which the port is located.
         It is an unsigned 16-bit integer that can take any value except
         0xFFFF.  The value 0xFFFF is used to indicate "unknown".  The
         Physical Slot Number is not used by the GSMP protocol.  It is
         provided to assist network management in functions such as
         logging, port naming, and graphical representation.

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      Physical Port Number
         The physical location of the port within the slot in which the
         port is located.  It is an unsigned 16-bit integer that can
         take any value except 0xFFFF.  The value 0xFFFF is used to
         indicate "unknown".  The Physical Port Number is not used by
         the GSMP protocol.  It is provided to assist network management
         in functions such as logging, port naming, and graphical
         representation.

         There MUST be a one to one mapping between the Port Number and
         the Physical Slot Number and Physical Port Number combination.
         Two different Port Numbers MUST NOT yield the same Physical
         Slot Number and Physical Port Number combination.  The same
         Port Number MUST yield the same Physical Slot Number and
         Physical Port Number within a single GSMP session.  If both
         Physical Slot Number and Physical Port Number indicate
         "unknown" the physical location of switch ports may be
         discovered by looking up the product identity in a database to
         reveal the physical interpretation of the 32-bit Port Number.

8.2.1.1  PortType Specific data for PortType=ATM

   If PortType=ATM, the Default Label Range Block has the following
   format:

    0                   1                   2                   3
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |x|x|V|x|   ATM Label (0x100)   |          Label Length         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |x x x x|           VPI         |              VCI              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

      V: Label
         If the Label flag is set, the message refers to a range of
         VPI's only.  The Min VCI and Max VCI fields are unused.  If the
         Label flag is zero the message refers to a range of VCI's on
         either one VPI or on a range of VPI's.

      Min VPI
         The default minimum value of dynamically assigned incoming VPI
         that the connection table on the input port supports and that
         may be controlled by GSMP.

      Max VPI
         The default maximum value of dynamically assigned incoming VPI
         that the connection table on the input port supports and that
         may be controlled by GSMP.

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         At power-on, after a hardware reset, and after the Reset Input
         Port function of the Port Management message, the input port
         MUST handle all values of VPI within the range Min VPI to Max
         VPI inclusive and GSMP MUST be able to control all values
         within this range.  It should be noted that the range Min VPI
         to Max VPI refers only to the incoming VPI range that can be
         supported by the associated port.  No restriction is placed on
         the values of outgoing VPI's that may be written into the cell
         header.  If the switch does not support virtual paths it is
         acceptable for both Min VPI and Max VPI to specify the same
         value, most likely zero.

         Use of the Label Range message allows the range of VPI's
         supported by the port to be changed.  However, the Min VPI and
         Max VPI fields in the Port Configuration and All Ports
         Configuration messages always report the same default values
         regardless of the operation of the Label Range message.

      Min VCI
         The default minimum value of a dynamically assigned incoming
         VCI that the connection table on the input port can support and
         may be controlled by GSMP.  This value is not changed as a
         result of the Label Range message.

      Max VCI
         The default maximum value of a dynamically assigned incoming
         VCI that the connection table on the input port can support and
         may be controlled by GSMP.

         At power-on, after a hardware reset, and after the Reset Input
         Port function of the Port Management message, the input port
         MUST handle all values of VCI within the range Min VCI to Max
         VCI inclusive, for each of the virtual paths in the range Min
         VPI to Max VPI inclusive, and GSMP MUST be able to control all
         values within this range.  It should be noted that the range
         Min VCI to Max VCI refers only to the incoming VCI range that
         can be supported by the associated port on each of the virtual
         paths in the range Min VPI to Max VPI.  No restriction is
         placed on the values of outgoing VCI's that may be written into
         the cell header.  Use of the Label Range message allows the
         range of VCI's to be changed on each VPI supported by the port.
         However, the Min VCI and Max VCI fields in the Port
         Configuration and All Ports Configuration messages always
         report the same default values regardless of the operation of
         the Label Range message.

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   For a port over which the GSMP protocol is operating, the VCI of the
   GSMP control channel may or may not be reported as lying within the
   range Min VCI to Max VCI.  A switch should honour a connection
   request message that specifies the VCI value of the GSMP control
   channel even if it lies outside the range Min VCI to Max VCI

8.2.1.2  PortType Specific data for PortType=FR

   If PortType=FR, the Default Label Range Block has the following
   format:

    0                   1                   2                   3
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |x|S|x|x|    FR Label (0x101)   |          Label Length         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |x x x x|Res|Len|                   DLCI                        |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

      Res
         The Res field is reserved in [21], i.e., it is not explicitly
         reserved by GSMP.

      Len
         This field specifies the number of bits of the DLCI.  The
         following values are supported:

         Len  DLCI bits
         0    10
         2    23

      Min DLCI, Max DLCI
         Specify a range of DLCI values, Min DLCI to Max DLCI inclusive.
         The values SHOULD be right justified in the 23-bit fields and
         the preceding bits SHOULD be set to zero.  A single DLCI may be
         specified with a Min DLCI and a Max DLCI having the same value.
         In a request message, if the value of the Max DLCI field is
         less than or equal to the value of the Min DLCI field, the
         requested range is a single DLCI with a value equal to the Min
         DLCI field.  Zero is a valid value.

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8.2.1.3  PortType Specific data for PortType=MPLS

   The Default Label Range Block for PortTypes using MPLS labels.  These
   types of labels are for use on links for which label values are
   independent of the underlying link technology.  Examples of such
   links are PPP and Ethernet.  On such links the labels are carried in
   MPLS label stacks [14].  Ports of the Type MPLS have the following
   format:

    0                   1                   2                   3
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |x|x|x|x| MPLS Gen Label (0x102)|          Label Length         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |x|x|x|x|x|x|x|x|x|x|x|x|              MPLS Label               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

      Min MPLS Label, Max MPLS Label
         Specify a range of MPLS label values, Min MPLS Label to Max
         MPLS Label inclusive.  The Max and Min MPLS label fields are 20
         bits each.

8.2.1.4  PortType Specific data for PortType=FEC

   The Default Label Range Block for PortTypes using FEC labels is not
   used.  The Label Range Count and Label Range Length fields defined in
   [8.2.1] should be set to 0.

8.3  All Ports Configuration Message

   The All Ports Configuration message requests the switch for the
   configuration information of all of its ports.  The All Ports
   Configuration message is:

      Message Type = 66

   The Port field is not used in the request message.

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   The All Ports Configuration success response message has the
   following format:

    0                   1                   2                   3
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |    Version    | Message Type  |    Result     |     Code      |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | Partition ID  |            Transaction Identifier             |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |I|      SubMessage Number      |           Length              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |x x x x x x x x x x x x x x x x|       Number of Records       |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   ~                          Port Records                         ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

      Note: Fields and Parameters that have been explained in the
         description of the general messages will not be explained in
         this section.  Please refer to section 3.1 for details.

      Number of Records
         Field gives the total number of Port Records to be returned in
         response to the All Ports Configuration request message.  The
         number of port records in a single All Ports Configuration
         success response MUST NOT cause the packet length to exceed the
         maximum transmission unit defined by the encapsulation.  If a
         switch has more ports than can be sent in a single success
         response message it MUST send multiple success response
         messages.  All success response messages that are sent in
         response to the same request message MUST have the same
         Transaction Identifier as the request message and the same
         value in the Number of Records field.  All success response
         messages that are sent in response to the same request message,
         except for the last message, MUST have the result field set to
         "More".  The last message, or a single success response
         message, MUST have the result field set to "Success".  All Port
         records within a success response message MUST be complete,
         i.e., a single Port record MUST NOT be split across multiple
         success response messages.

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      Port Records
         Follow in the remainder of the message.  Each port record has
         the following format:

    0                   1                   2                   3
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                             Port                              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                       Port Session Number                     |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                      Event Sequence Number                    |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |          Event Flags          |     Port Attribute Flags      |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |   PortType    |S|x|x|x|x|x|x|x|      Data Fields Length       |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   ~                     PortType Specific Data                    ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |x x x x x x x x x x x x x x x x|    Number of Service Specs    |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   ~                      Service Specs List                       ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   The definition of the fields in the Port Record is exactly the same
   as that of the Port Configuration message [section 8.2].

8.4  Service Configuration Message

   The Service Configuration message requests the switch for the
   configuration information of the Services that are supported.  The
   Service Configuration message is:

      Message Type = 67

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   The Service Configuration success response message has the following
   format:

    0                   1                   2                   3
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |    Version    | Message Type  |    Result     |     Code      |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | Partition ID  |            Transaction Identifier             |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |I|      SubMessage Number      |           Length              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |x x x x x x x x x x x x x x x x|   Number of Service Records   |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   ~                        Service Records                        ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

      Note: Fields and Parameters that have been explained in the
         description of the general messages will not be explained in
         this section.  Please refer to section 3.1 for details.

      Number of Service Records
         Field gives the total number of Service Records to be returned
         in the Service Records field.

      Service Records
         A sequence of zero or more Service Records.  The switch returns
         one Service Record for each Service that it supports on any of
         its ports.  A Service record contains the configuration data of
         the specified Service.  Each Service Record has the following
         format:

    0                   1                   2                   3
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |          Service ID           |  Number of Cap. Set. Records  |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   ~                     Capability Set Records                    ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

      Service ID
         The Service ID Field identifies the Service supported by the
         port.  The Services are defined with their Service ID values as
         described in section 10.2.

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      Number of Cap. Set. Records
         Field gives the total number of Capability Set Records to be
         returned in the Service Record field.

      Capability Set Records
         The switch returns one or more Capability Set Records in each
         Service Record.  A Capability Set contains a set of parameters
         that describe the QoS parameter values and traffic controls
         that apply to an instance of the Service.  Each Capability Set
         record has the following format:

    0                   1                   2                   3
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |          Cap. Set ID          |       Traffic Controls        |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |     CLR       |                     CTD                       |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |   Frequency   |                     CDV                       |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

      Capability Set ID
         The value in this Field defines a Capability Set ID supported
         by the switch.  The values of a Capability Set ID are assigned
         by the switch and used in Port Configuration messages to
         identify Capability Sets supported by individual ports.  Each
         Capability Set Record within a Service Record MUST have a
         unique Capability Set ID.

      Traffic Controls
         Field identifies the availability of Traffic Controls within
         the Capability Set.  Traffic Controls are defined as part of
         the respective Service definition, see Chapter 10.  Some or all
         of the Traffic Controls may be undefined for a given Service,
         in which case the corresponding Flag is ignored by the
         controller.  The Traffic Controls field is formatted into
         Traffic Control Sub-fields as follows:

             0                   1
             0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
            +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
            | U | D | I | E | S | V |x x x x|
            +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

         Traffic Control Sub-fields have the following encoding:

            0b00 Indicates that the Traffic Control is not available in
                 the Capability Set.

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            0b01 Indicates that the Traffic Control is applied to all
                 connections that use the Capability Set.

            0b10 Indicates that the Traffic Control is available for
                 application to connections that use the Capability Set
                 on a per connection basis.

            0b11 Reserved

         Traffic Control Sub-fields:

            U: Usage Parameter Control
                 The Usage Parameter Control sub-field indicates the
                 availability of Usage Parameter Control for the
                 specified Service and Capability Set.

            D: Packet Discard
                 The Packet Discard sub-field indicates the availability
                 of Packet Discard for the specified Service and
                 Capability Set.

            I: Ingress Shaping
                 The Ingress Shaping sub-field indicates the
                 availability of Ingress Traffic Shaping to the Peak
                 Cell Rate and Cell Delay Variation Tolerance for the
                 specified Service and Capability Set.

            E: Egress Shaping, Peak Rate
                 The Egress Shaping, Peak Rate sub-field indicates the
                 availability of Egress Shaping to the Peak Cell Rate
                 and Cell Delay Variation Tolerance for the specified
                 Service and Capability Set.

            S: Egress Traffic Shaping, Sustainable Rate
                 The Egress Shaping, Sustainable Rate sub-field, if set,
                 indicates that Egress Traffic Shaping to the
                 Sustainable Cell Rate and Maximum Burst Size is
                 available for the specified Service and Capability Set.

            V: VC Merge
                 The VC Merge sub-field indicates the availability of
                 ATM Virtual Channel Merge (i.e., multipoint to point
                 ATM switching with a traffic control to avoid AAL5 PDU
                 interleaving) capability for the specified Service and
                 Capability Set.

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      QoS Parameters
         The remaining four fields in the Capability Set Record contain
         the values of QoS Parameters.  QoS Parameters are defined as
         part of the respective Service definition, see Chapter 9.6.
         Some or all of the QoS Parameters may be undefined for a given
         Service, in which case the corresponding field is ignored by
         the controller.

            CLR: Cell Loss Ratio
                 The Cell Loss Ratio parameter indicates the CLR
                 guaranteed by the switch for the specified Service.  A
                 cell loss ratio is expressed as an order of magnitude
                 n, where the CLR takes the value of ten raised to the
                 power of -n, i.e., log(CLR)=-n.  The value n is coded
                 as a binary integer, having a range of 1 <= n <= 15.
                 In addition, the value 0b1111 1111 indicates that no
                 CLR guarantees are given.

            Frequency
                 The frequency field is coded as an 8 bit unsigned
                 integer.  Frequency applies to the MPLS CR-LDP Service
                 (see Section 10.4.3).  Valid values of Frequency are:

                 0 - Very frequent
                 1 - Frequent
                 2 - Unspecified

            CTD: Cell Transfer Delay
                 The CTD value is expressed in units of microseconds.
                 It is coded as a 24-bit integer.

            CDV: Peak-to-peak Cell Delay Variation
                 The CDV value is expressed in units of microseconds.
                 It is coded as a 24-bit integer.

9.  Event Messages

   Event messages allow the switch to inform the controller of certain
   asynchronous events.  By default the controller does not acknowledge
   event messages unless ReturnReceipt is set in the Result field.  The
   Code field is only used in case of Adjacency Update message,
   otherwise it is not used and SHOULD be set to zero.  Event messages
   are not sent during initialisation.  Event messages have the
   following format:

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    0                   1                   2                   3
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |    Version    | Message Type  |    Result     |     Code      |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | Partition ID  |            Transaction Identifier             |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |I|      SubMessage Number      |           Length              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                             Port                              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                      Port Session Number                      |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                     Event Sequence Number                     |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |x|S|x|x|                                                       |
   +-+-+-+-+                     Label                             |
   ~                                                               ~
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

      Note: Fields and Parameters that have been explained in the
         description of the general messages will not be explained in
         this section.  Please refer to section 3.1 for details.

      Event Sequence Number
         The current value of the Event Sequence Number for the
         specified port.  The Event Sequence Number is set to zero when
         the port is initialised.  It is incremented by one each time
         the port detects an asynchronous event that the switch would
         normally report via an Event message.  The Event Sequence
         Number MUST be incremented each time an event occurs even if
         the switch is prevented from sending an Event message due to
         the action of the flow control.

      Label
         Field gives the Label to which the event message refers.  If
         this field is not required by the event message it is set to
         zero.

   Each switch port MUST maintain an Event Sequence Number and a set of
   Event Flags, one Event Flag for each type of Event message.  When a
   switch sends an Event message it MUST set the Event Flag for that
   port corresponding to the Event type.  If Flow Control is activated
   for this Event type for this Port then the switch MUST NOT send
   another Event message of the same type for that port until the Event
   Flag has been reset.  Event Flags are reset by the "Reset Event
   Flags" function of the Port Management message.  This is a simple
   flow control preventing the switch from flooding the controller with

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   event messages.  The Event Sequence Number of the port MUST be
   incremented every time an event is detected on that port even if the
   port is prevented from reporting the event due to the action of the
   flow control.  This allows the controller to detect that it has not
   been informed of some events that have occurred on the port due to
   the action of the flow control.

9.1  Port Up Message

   The Port Up message informs the controller that the Line Status of a
   port has changed from, either the Down or Test state to the Up state.
   When the Line Status of a switch port changes to the Up state from
   either the Down or Test state a new Port Session Number MUST be
   generated, preferably using some form of random number.  The new Port
   Session Number is given in the Port Session Number field.  The Label
   field is not used and is set to zero.  The Port Up message is:

      Message Type = 80

9.2  Port Down Message

   The Port Down message informs the controller that the Line Status of
   a port has changed from the Up state or Test state to the Down state.
   This message will be sent to report link failure if the switch is
   capable of detecting link failure.  The port session number that was
   valid before the port went down is reported in the Port Session
   Number field.  The Label field is not used and is set to zero.  The
   Port Down message is:

      Message Type = 81

9.3  Invalid Label Message

   The Invalid Label message is sent to inform the controller that one
   or more cells or frames have arrived at an input port with a Label
   that is currently not allocated to an assigned connection.  The input
   port is indicated in the Port field, and the Label in the Label
   field.  The Invalid Label message is:

      Message Type = 82

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9.4  New Port Message

   The New Port message informs the controller that a new port has been
   added to the switch.  The port number of the new port is given in the
   Port field.  A new Port Session Number MUST be assigned, preferably
   using some form of random number.  The new Port Session Number is
   given in the Port Session Number field.  The state of the new port is
   undefined so the Label field is not used and is set to zero.  The New
   Port message is:

      Message Type = 83

9.5  Dead Port Message

   The Dead Port message informs the controller that a port has been
   removed from the switch.  The port number of the port is given in the
   Port field.  The Port Session Number that was valid before the port
   was removed is reported in the Port Session Number field.  The Label
   fields are not used and are set to zero.  The Dead Port message is:

      Message Type = 84

9.6  Adjacency Update Message

   The Adjacency Update message informs the controller when adjacencies,
   i.e., other controllers controlling a specific partition, are joining
   or leaving.  When a new adjacency has been established, the switch
   sends an Adjacency Update message to every controller with an
   established adjacency to that partition.  The Adjacency Update
   message is also sent when adjacency is lost between the partition and
   a controller, provided that there are any remaining adjacencies with
   that partition.  The Code field is used to indicate the number of
   adjacencies known by the switch partition.  The Label field is not
   used and SHOULD be set to zero.  The Adjacency Update message is:

      Message Type = 85

10.  Service Model Definition

10.1  Overview

   In the GSMP Service Model a controller may request the switch to
   establish a connection with a given Service.  The requested Service
   is identified by including a Service ID in the Add Branch message or
   the Reservation Message.  The Service ID refers to a Service
   Definition provided in this chapter of the GSMP specification.

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   A switch that implements one or more of the Services, as defined
   below, advertises the availability of these Services in the Service
   Configuration message response (see Section 8.4).  Details of the
   switch's implementation of a given Service that are important to the
   controller (e.g., the value of delay or loss bounds or the
   availability of traffic controls such as policers or shapers) are
   reported in the form of a Capability Set in the Service Configuration
   message response.

   Thus a switch's implementation of a Service is defined in two parts:
   the Service Definition, which is part of the GSMP specification, and
   the Capability Set, which describes attributes of the Service
   specific to the switch.  A switch may support more than one
   Capability Set for a given Service.  For example if a switch supports
   one Service with two different values of a delay bound it could do
   this by reporting two Capability Sets for that Service.

   The Service Definition is identified in GSMP messages by the Service
   ID, a sixteen-bit identifier.  Assigned numbers for the Service ID
   are given with the Service Definitions in Section 10.4.  The
   Capability Set is identified in GSMP messages by the Capability Set
   ID, a sixteen-bit identifier.  Numbers for the Capability Set ID are
   assigned by the switch and are advertised in the Service
   Configuration message response.

   The switch reports all its supported Services and Capability Sets in
   the Service Configuration message response.  The subset of Services
   and Capability Sets supported on an individual port is reported in
   the Port Configuration message response or in the All Ports
   Configuration message response.  In these messages the Services and
   Capability Sets supported on the specified port are indicated by a
   list of {Service ID, Capability Set ID} number pairs.

10.2  Service Model Definitions

   Terms and objects defined for the GSMP Service Model are given in
   this section.

10.2.1  Original Specifications

   Services in GSMP are defined largely with reference to Original
   Specifications, i.e., the standards or implementation agreements
   published by organisations such as ITU-T, IETF, and ATM Forum that
   originally defined the Service.  This version of GSMP refers to 4
   original specifications: [8], [9], [10] and [11].

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10.2.2  Service Definitions

   Each Service Definition in GSMP includes definition of:

      Traffic Parameters
         Traffic Parameter definitions are associated with Services
         while Traffic Parameter values are associated with connections.

         Traffic Parameters quantitatively describe a connection's
         requirements on the Service.  For example, Peak Cell Rate is a
         Traffic Parameter of the Service defined by the ATM Forum
         Constant Bit Rate Service Category.

         Some Traffic Parameters are mandatory and some are optional,
         depending on the Service.

         Semantics of Traffic Parameters are defined by reference to
         Original Specifications.

      QoS Parameters
         QoS Parameters and their values are associated with Services.

         QoS Parameters express quantitative characteristics of a
         switch's support of a Service.  They include, for example,
         quantitative bounds on switch induced loss and delay.

         Some QoS Parameters will be mandatory and some will be
         optional.

         Semantics of QoS Parameters are defined by reference to
         Original Specifications.

      Traffic Controls
         The implementation of some Services may include the use of
         Traffic Controls.  Traffic Controls include, for example
         functions such as policing, input shaping, output shaping,
         tagging and marking, frame vs. cell merge, frame vs. cell
         discard.

         Switches are not required to support Traffic Controls.  Any
         function that is always required in the implementation of a
         Service is considered part of the Service and is not considered
         a Traffic Control.

         If a switch supports a Traffic Control then the control may be
         applied either to all connections that use a given Capability
         Set (see below) or to individual connections.

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         The definition of a Traffic Control is associated with a
         Service.  Traffic Controls are defined, as far as possible, by
         reference to Original Specifications.

10.2.3  Capability Sets

   For each Service that a switch supports the switch MUST also support
   at least one Capability Set.  A Capability Set establishes
   characteristics of a switch's implementation of a Service.  It may be
   appropriate for a switch to support more than one Capability Set for
   a given Service.

   A Capability Set may contain, depending on the Service definition,
   QoS Parameter values and an indication of availability of Traffic
   Controls.

   If a switch reports QoS Parameter values in a Capability Set then
   these apply to all the connections that use that Capability Set.

   For each Traffic Control defined for a given Service the switch
   reports availability of that control as one of the following:

      Not available in the Capability Set,

      Applied to all connections that use the Capability Set, or

      Available for application to connections that use the Capability
      Set on a per connection basis.  In this case, a controller may
      request application of the Traffic Control in connection
      management messages.

10.3  Service Model Procedures

   A switch's Services and Capability Sets are reported to a controller
   in a Service Configuration message.  A Service Configuration message
   response includes the list of Services defined for GSMP that the
   switch supports and, for each Service, a specification of the
   Capability Sets supported for the Service.  Services are referred to
   by numbers standardised in the GSMP specification.  Capability Sets
   are referred to by a numbering system reported by the switch.  Each
   Capability Set within a given Service includes a unique identifying
   number together with the switch's specification of QoS Parameters and
   Traffic Controls.

   A switch need not support all the defined Services and Capability
   Sets on every port.  The supported Services and Capability Sets are
   reported to the controller on a per port basis in port configuration
   messages.  Port configuration response messages list the supported

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   Services using the standardised identifying numbers and the
   Capability Sets by using the identifying numbers established in the
   switch Service configuration messages.

   GSMP does not provide a negotiation mechanism by which a controller
   may establish or modify Capability Sets.

   When a controller establishes a connection, the connection management
   message includes indication of the Service and the Capability Set.
   Depending on these the connection management message may additionally
   include Traffic Parameter values and Traffic Control flags.

   A connection with a given Service can only be established if both the
   requested Service and the requested Capability Set are available on
   all of the connection's input and output ports.

   Refresh of an extant connection is permitted but the add branch
   message requesting the message MUST NOT include indication of
   Service, Capability Sets or Traffic Parameters.

   An extant connection's Traffic Parameters may be changed without
   first deleting the connection.  The Service and Capability Sets of an
   extant connection cannot be changed.

   Move branch messages may be refused on the grounds of resource
   depletion.



(page 100 continued on part 5)

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