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RFC 3015

 
 
 

Megaco Protocol Version 1.0

Part 4 of 6, p. 75 to 112
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12. PACKAGE DEFINITION

   The primary mechanism for extension is by means of Packages. Packages
   define additional Properties, Events, Signals and Statistics that may
   occur on Terminations.

   Packages defined by IETF will appear in separate RFCs.

   Packages defined by ITU-T may appear in the relevant recommendations
   (e.g. as annexes).

   1. A public document or a standard forum document, which can be
      referenced as the document that describes the package following
      the guideline above, should be specified.

   2. The document shall specify the version of the Package that it
      describes.

   3. The document should be available on a public web server and should
      have a stable URL. The site should provide a mechanism to provide
      comments and appropriate responses should be returned.

12.1 Guidelines for defining packages

   Packages define Properties, Events, Signals, and Statistics.

   Packages may also define new error codes according to the guidelines
   given in section 13.2. This is a matter of documentary convenience:
   the package documentation is submitted to IANA in support of the
   error code registration. If a package is modified, it is unnecessary
   to provide IANA with a new document reference in support of the error
   code unless the description of the error code itself is modified.

   Names of all such defined constructs shall consist of the PackageID
   (which uniquely identifies the package) and the ID of the item (which
   uniquely identifies the item in that package).  In the text encoding
   the two shall be separated by a forward slash ("/") character.
   Example: togen/playtone is the text encoding to refer to the play
   tone signal in the tone generation package.

   A Package will contain the following sections:

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12.1.1 Package

   Overall description of the package, specifying:

   *  Package Name: only descriptive,
   *  PackageID:  Is an identifier
   *  Description:
   *  Version: A new version of a package can only add additional
      Properties, Events, Signals, Statistics and new possible values
      for an existing parameter described in the original package. No
      deletions or modifications shall be allowed. A version is  an
      integer in the range from 1 to 99.

   *  Extends (Optional): A package may extend an existing package. The
      version of the original package must be specified. When a package
      extends another package it shall only add additional Properties,
      Events, Signals, Statistics and new possible values for an
      existing parameter described in the original package. An extended
      package shall not redefine or overload a name defined in the
      original package.  Hence, if package B version 1 extends package A
      version 1, version 2 of B will not be able to extend the A version
      2 if A version 2 defines a name already in B version 1.

12.1.2 Properties

   Properties defined by the package, specifying:

   *  Property Name: only descriptive.
   *  PropertyID:  Is an identifier
   *  Description:
   *  Type: One of:
      String: UTF-8 string
      Integer: 4 byte signed integer
      Double: 8 byte signed integer
      Character: Unicode UTF-8 encoding of a single letter.
                 Could be more than one octet.
         Enumeration: One of a list of possible unique values (See 12.3)
         Sub-list: A list of several values from a list
         Boolean

   *  Possible Values:
   *  Defined in: Which Megaco descriptor the property is defined in.
      LocalControl is for stream dependent properties. TerminationState
      is for stream independent properties.  These are expected to be
      the most common cases, but it is possible for properties to be
      defined in other descriptors.

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   *  Characteristics: Read / Write or both, and (optionally), global:
      Indicates whether a property is read-only, or read-write, and if
      it is global.  If Global is omitted, the property is not global.
      If a property is declared as global, the value of the property is
      shared by all terminations realizing the package.

12.1.3 Events

   Events defined by the package, specifying:

   *  Event name: only descriptive.
   *  EventID:  Is an identifier
   *  Description:
   *  EventsDescriptor Parameters: Parameters used by the MGC to
      configure the event, and found in the EventsDescriptor.  See
      section 12.2.

   *  ObservedEventsDescriptor Parameters: Parameters returned to the
      MGC in  Notify requests and in replies to command requests from
      the MGC that audit ObservedEventsDescriptor, and found in the
      ObservedEventsDescriptor.  See section 12.2.

12.1.4 Signals

   *  Signals defined by the package, specifying:
   *  Signal Name: only descriptive.
   *  SignalID:  Is an identifier. SignalID is used in a
      SignalsDescriptor
   *  Description
   * SignalType: One of:
      -  OO (On/Off)
      -  TO (TimeOut)
      -  BR (Brief)

         Note -  SignalType may be defined such that it is dependent on
         the value of one or more parameters. Signals that would be
         played with SignalType BR or TO should have a default duration.
         The package has to define the default duration and signalType.

   *  Duration: in hundredths of seconds
   *  Additional Parameters: See section 12.2

12.1.5 Statistics

   Statistics defined by the package, specifying:

   *  Statistic name: only descriptive.

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   *  StatisticID:  Is an identifier.  StatisticID is used in a
      StatisticsDescriptor.
   *  Description
   *  Units: unit of measure, e.g. milliseconds, packets.

12.1.6 Procedures

   Additional guidance on the use of the package.

12.2 Guidelines to defining Properties, Statistics and Parameters to
   Events and Signals.

   *  Parameter Name: only descriptive
   *  ParameterID: Is an identifier
   *  Type: One of:
         String: UTF-8 octet string
         Integer: 4 octet signed integer
         Double: 8 octet signed integer
         Character: Unicode UTF-8 encoding of a single letter. Could be
         more than one octet.
         Enumeration: One of a list of possible unique values (See 12.3)
         Sub-list: A list of several values from a list (not supported
         for statistics)
         Boolean

   *  Possible values:
   *  Description:

12.3 Lists

   Possible values for parameters include enumerations.  Enumerations
   may be defined in a list.  It is recommended that the list be IANA
   registered so that packages that extend the list can be defined
   without concern for conflicting names.

12.4 Identifiers

   Identifiers in text encoding shall be strings of up to 64 characters,
   containing no spaces, starting with an alphanumeric character and
   consisting of alphanumeric characters and / or digits, and possibly
   including the special character underscore ("_").

   Identifiers in binary encoding are 2 octets long.

   Both text and binary values shall be specified for each identifier,
   including identifiers used as values in enumerated types.

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12.5 Package Registration

   A package can be registered with IANA for interoperability reasons.
   See section 13 for IANA considerations.

13.  IANA CONSIDERATIONS

13.1 Packages

   The following considerations SHALL be met to register a package with
   IANA:

   1. A unique string name, unique serial number and version number is
      registered for each package.  The string name is used with text
      encoding.  The serial number shall be used with binary encoding.
      Serial Numbers 60000-64565 are reserved for private use. Serial
      number 0 is reserved.

   2. A contact name, email and postal addresses for that contact shall
      be specified.  The contact information shall be updated by the
      defining organization as necessary.

   3. A reference to a document that describes the package, which should
      be public:

      The document shall specify the version of the Package that it
      describes.

      If the document is public, it should be located on a public web
      server and should have a stable URL. The site should provide a
      mechanism to provide comments and appropriate responses should be
      returned.

   4. Packages registered by other than recognized standards bodies
      shall have a minimum package name length of 8 characters.

   5. All other package names are first come-first served if all other
      conditions are met

13.2 Error Codes

   The following considerations SHALL be met to register an error code
   with IANA:

   1. An error number and a one line (80 character maximum) string is
      registered for each error.

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   2. A complete description of the conditions under which the error is
      detected shall be included in a publicly available document.  The
      description shall be sufficiently clear to differentiate the error
      from all other existing error codes.

   3. The document should be available on a public web server and should
      have a stable URL.

   4. Error numbers registered by recognized standards bodies shall have
      3 or 4 character error numbers.

   5. Error numbers registered by all other organizations or individuals
      shall have 4 character error numbers.

   6. An error number shall not be redefined, nor modified except by the
      organization or individual that originally defined it, or their
      successors or assigns.

13.3 ServiceChange Reasons

   The following considerations SHALL be met to register service change
   reason with IANA:

   1. A one phrase, 80-character maximum, unique reason code is
      registered for each reason.

   2. A complete description of the conditions under which the reason is
      used is detected shall be included in a publicly available
      document.  The description shall be sufficiently clear to
      differentiate the reason from all other existing reasons.

   3. The document should be available on a public web server and should
      have a stable URL.

ANNEX A: BINARY ENCODING OF THE PROTOCOL (NORMATIVE)

   This Annex specifies the syntax of messages using the notation
   defined in ASN.1 [ITU-T Recommendation X.680 (1997): Information
   Technology - Abstract Syntax Notation One (ASN.1) - Specification of
   basic notation.]. Messages shall be encoded for transmission by
   applying the basic encoding rules specified in [ITU-T Recommendation
   X.690(1994) Information Technology - ASN.1  Encoding Rules:
   Specification  of  Basic  Encoding Rules  (BER)].

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A.1 Coding of wildcars

   The use of wildcards ALL and CHOOSE is allowed in the protocol. This
   allows a MGC to partially specify Termination IDs and let the MG
   choose from the values that conform to the partial specification.
   Termination IDs may encode a hierarchy of names.  This hierarchy is
   provisioned. For instance, a TerminationID may consist of a trunk
   group, a trunk within the group and a circuit.  Wildcarding must be
   possible at all levels.  The following paragraphs explain how this is
   achieved.

   The ASN.1 description uses octet strings of up to 8 octets in length
   for Termination IDs.  This means that Termination IDs consist of at
   most 64 bits.  A fully specified Termination ID may be preceded by a
   sequence of wildcarding fields.  A wildcarding field is one octet in
   length.  Bit 7 (the most significant bit) of this octet specifies
   what type of wildcarding is invoked:  if the bit value equals 1, then
   the ALL wildcard is used; if the bit value if 0, then the CHOOSE
   wildcard is used.  Bit 6 of the wildcarding field specifies whether
   the wildcarding pertains to one level in the hierarchical naming
   scheme (bit value 0) or to the level of the hierarchy specified in
   the wildcarding field plus all lower levels (bit value 1).  Bits 0
   through 5 of the wildcarding field specify the bit position in the
   Termination ID at which the starts.

   We illustrate this scheme with some examples.  In these examples, the
   most significant bit in a string of bits appears on the left hand
   side.

   Assume that Termination IDs are three octets long and that each octet
   represents a level in a hierarchical naming scheme.  A valid
   Termination ID is

         00000001 00011110 01010101.

   Addressing ALL names with prefix 00000001 00011110 is done as
   follows:

         wildcarding field: 10000111
         Termination ID: 00000001 00011110 xxxxxxxx.

   The values of the bits labeled "x" is irrelevant and shall be ignored
   by the receiver.

   Indicating to the receiver that is must choose a name with 00011110
   as the second octet is done as follows:

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         wildcarding fields: 00010111 followed by 00000111
         Termination ID: xxxxxxxx 00011110 xxxxxxxx.

   The first wildcard field indicates a CHOOSE wildcard for the level in
   the naming hierarchy starting at bit 23, the highest level in our
   assumed naming scheme.  The second wildcard field indicates a CHOOSE
   wildcard for the level in the naming hierarchy starting at bit 7, the
   lowest level in our assumed naming scheme.

   Finally, a CHOOSE-wildcarded name with the highest level of the name
   equal to 00000001 is specified as follows:

         wildcard field: 01001111
         Termination ID: 0000001 xxxxxxxx xxxxxxxx .

   Bit value 1 at bit position 6 of the first octet of the wildcard
   field indicates that the wildcarding pertains to the specified level
   in the naming hierarchy and all lower levels.

   Context IDs may also be wildcarded.  In the case of Context IDs,
   however, specifying partial names is not allowed.  Context ID 0x0
   SHALL be used to indicate the NULL Context, Context ID 0xFFFFFFFE
   SHALL be used to indicate a CHOOSE wildcard, and Context ID
   0xFFFFFFFF SHALL be used to indicate an ALL wildcard.

   TerminationID 0xFFFFFFFFFFFFFFFF SHALL be used to indicate the ROOT
   Termination.

A.2 ASN.1 syntax specification

   This section contains the ASN.1 specification of the H.248 protocol
   syntax.

   NOTE - In case a transport mechanism is used that employs application
   level framing, the definition of Transaction below changes.  Refer to
   the annex defining the transport mechanism for the definition that
   applies in that case.

   NOTE - The ASN.1 specification below contains a clause defining
   TerminationIDList as a sequence of TerminationIDs.  The length of
   this sequence SHALL be one, except possibly when used in
   contextAuditResult.

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   MEDIA-GATEWAY-CONTROL DEFINITIONS AUTOMATIC TAGS::= BEGIN

   MegacoMessage ::= SEQUENCE
   {
        authHeader      AuthenticationHeader OPTIONAL,
        mess            Message
   }
   AuthenticationHeader ::= SEQUENCE
   {
        secParmIndex    SecurityParmIndex,
        seqNum          SequenceNum,
        ad              AuthData
   }

   SecurityParmIndex ::= OCTET STRING(SIZE(4))

   SequenceNum       ::= OCTET STRING(SIZE(4))

   AuthData          ::= OCTET STRING (SIZE (12..32))

   Message ::= SEQUENCE
   {    version         INTEGER(0..99),
        -- The version of the protocol defined here is equal to 1.
        mId             MId,    -- Name/address of message originator
        messageBody             CHOICE
        {
                messageError    ErrorDescriptor,
                transactions    SEQUENCE OF Transaction
        },
        ...
   }

   MId ::= CHOICE
   {
        ip4Address                      IP4Address,
        ip6Address                      IP6Address,
        domainName                      DomainName,
        deviceName                      PathName,
        mtpAddress                      OCTET STRING(SIZE(2)),
    -- Addressing structure of mtpAddress:
    --        15                0
    --        |  PC        | NI |
    --           14 bits    2 bits
         ...
   }

   DomainName ::= SEQUENCE
   {

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        name            IA5String,
        -- The name starts with an alphanumeric digit followed by a
        -- sequence of alphanumeric digits, hyphens and dots.  No two
        -- dots shall occur consecutively.
        portNumber      INTEGER(0..65535) OPTIONAL
   }

   {
        address         OCTET STRING (SIZE(4)),
        portNumber      INTEGER(0..65535) OPTIONAL
   }

   IP6Address ::= SEQUENCE
   {
        address         OCTET STRING (SIZE(16)),
        portNumber      INTEGER(0..65535) OPTIONAL
   }

   PathName ::= IA5String(SIZE (1..64))
   -- See section A.3

   Transaction ::= CHOICE
   {
        transactionRequest      TransactionRequest,
        transactionPending      TransactionPending,
        transactionReply        TransactionReply,
        transactionResponseAck  TransactionResponseAck,
             -- use of response acks is dependent on underlying
   transport
        ...
   }

   TransactionId ::= INTEGER(0..4294967295)  -- 32 bit unsigned integer

   TransactionRequest ::= SEQUENCE
   {
        transactionId           TransactionId,
        actions                 SEQUENCE OF ActionRequest,
        ...
   }

   TransactionPending ::= SEQUENCE
   {
        transactionId           TransactionId,
        ...
   }

   TransactionReply ::= SEQUENCE

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   {
        transactionId           TransactionId,
        immAckRequired          NULL OPTIONAL,  transactionResult
        CHOICE
        {
             transactionError   ErrorDescriptor,
             actionReplies      SEQUENCE OF ActionReply
        },
        ...
   }

   TransactionResponseAck ::= SEQUENCE
   {
        firstAck        TransactionId,
        lastAck         TransactionId OPTIONAL
   }

   ErrorDescriptor ::= SEQUENCE
   {
        errorCode       ErrorCode,
        errorText       ErrorText OPTIONAL
   }

   ErrorCode ::= INTEGER(0..65535)
   -- See section 13 for IANA considerations w.r.t. error codes

   ErrorText ::= IA5String

   ContextID ::= INTEGER(0..4294967295)

   -- Context NULL Value: 0
   -- Context CHOOSE Value: 429467294 (0xFFFFFFFE)
   -- Context ALL Value: 4294967295 (0xFFFFFFFF)


   ActionRequest ::= SEQUENCE
   {
        contextId               ContextID,
        contextRequest          ContextRequest OPTIONAL,
        contextAttrAuditReq     ContextAttrAuditRequest OPTIONAL,
        commandRequests         SEQUENCE OF CommandRequest
   }

   ActionReply ::= SEQUENCE
   {
        contextId               ContextID,
        errorDescriptor         ErrorDescriptor OPTIONAL,
        contextReply            ContextRequest OPTIONAL,

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        commandReply            SEQUENCE OF CommandReply
   }

   ContextRequest ::= SEQUENCE
   {
        priority                INTEGER(0..15) OPTIONAL,
        emergency               BOOLEAN OPTIONAL,
        topologyReq             SEQUENCE OF TopologyRequest OPTIONAL,
        ...
   }

   ContextAttrAuditRequest ::= SEQUENCE
   {
   topology     NULL OPTIONAL,
        emergency       NULL OPTIONAL,
        priority        NULL OPTIONAL,
        ...
   }

   CommandRequest ::= SEQUENCE
   {
        command                 Command,
        optional                NULL OPTIONAL,
        wildcardReturn          NULL OPTIONAL,
        ...
   }

   Command ::= CHOICE
   {
        addReq                  AmmRequest,
        moveReq                 AmmRequest,
        modReq                  AmmRequest,
        -- Add, Move, Modify requests have the same parameters
        subtractReq             SubtractRequest,
        auditCapRequest         AuditRequest,
        auditValueRequest       AuditRequest,
        notifyReq               NotifyRequest,
        serviceChangeReq        ServiceChangeRequest,
        ...
   }

   CommandReply ::= CHOICE
   {
        addReply                AmmsReply,
        moveReply               AmmsReply,
        modReply                AmmsReply,
        subtractReply           AmmsReply,
        -- Add, Move, Modify, Subtract replies have the same parameters

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        auditCapReply           AuditReply,
        auditValueReply         AuditReply,
        notifyReply             NotifyReply,
        serviceChangeReply      ServiceChangeReply,
        ...
   }

   TopologyRequest ::= SEQUENCE
   {
        terminationFrom         TerminationID,
        terminationTo           TerminationID,
        topologyDirection       ENUMERATED
        {
                bothway(0),
                isolate(1),
                oneway(2)
        }
   }

   AmmRequest ::= SEQUENCE
   {
        terminationID           TerminationIDList,
        descriptors             SEQUENCE OF     AmmDescriptor,
        -- At most one descriptor of each type (see AmmDescriptor)
        -- allowed in the sequence.
        ...
   }

   AmmDescriptor ::= CHOICE
   {
        mediaDescriptor                 MediaDescriptor,
        modemDescriptor                 ModemDescriptor,
        muxDescriptor                   MuxDescriptor,
        eventsDescriptor                EventsDescriptor,
        eventBufferDescriptor           EventBufferDescriptor,
        signalsDescriptor               SignalsDescriptor,
        digitMapDescriptor              DigitMapDescriptor,
        auditDescriptor                 AuditDescriptor,
        ...
   }

   AmmsReply ::= SEQUENCE
   {
        terminationID           TerminationIDList,
        terminationAudit        TerminationAudit OPTIONAL,
        ...
   }

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   SubtractRequest ::= SEQUENCE
   {
        terminationID           TerminationIDList,
        auditDescriptor         AuditDescriptor OPTIONAL,
        ...
   }

   AuditRequest ::= SEQUENCE
   {
        terminationID           TerminationID,
        auditDescriptor         AuditDescriptor,
        ...
   }

   AuditReply ::= SEQUENCE
   {
        terminationID           TerminationID,
        auditResult             AuditResult,
        ...
   }

   AuditResult ::= CHOICE
   {
        contextAuditResult      TerminationIDList,
        terminationAuditResult  TerminationAudit
   }



   TerminationAudit ::= SEQUENCE OF AuditReturnParameter

   AuditReturnParameter ::= CHOICE
   {
        errorDescriptor                 ErrorDescriptor,
        mediaDescriptor                 MediaDescriptor,
        modemDescriptor                 ModemDescriptor,
        muxDescriptor                   MuxDescriptor,
        eventsDescriptor                EventsDescriptor,
        eventBufferDescriptor           EventBufferDescriptor,
        signalsDescriptor               SignalsDescriptor,
        digitMapDescriptor              DigitMapDescriptor,
        observedEventsDescriptor        ObservedEventsDescriptor,
        statisticsDescriptor            StatisticsDescriptor,
        packagesDescriptor              PackagesDescriptor,
        emptyDescriptors                AuditDescriptor,
        ...
   }

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   AuditDescriptor ::= SEQUENCE
   {
        auditToken      BIT STRING
        {
                muxToken(0), modemToken(1), mediaToken(2),
                eventsToken(3), signalsToken(4),
                digitMapToken(5), statsToken(6),
                observedEventsToken(7),
                packagesToken(8), eventBufferToken(9)
        } OPTIONAL,
        ...
   }

   NotifyRequest ::= SEQUENCE
   {
        terminationID                   TerminationIDList,
        observedEventsDescriptor        ObservedEventsDescriptor,
        errorDescriptor                 ErrorDescriptor OPTIONAL,
        ...
   }

   NotifyReply ::= SEQUENCE
   {
        terminationID                   TerminationIDList OPTIONAL,
        errorDescriptor                 ErrorDescriptor OPTIONAL,
        ...
   }

   ObservedEventsDescriptor ::= SEQUENCE
   {
        requestId                       RequestID,
        observedEventLst                SEQUENCE OF ObservedEvent
   }

   ObservedEvent ::= SEQUENCE
   {
        eventName                       EventName,
        streamID                        StreamID OPTIONAL,
        eventParList                    SEQUENCE OF EventParameter,
        timeNotation                    TimeNotation OPTIONAL,
        ...
   }

   EventName ::= PkgdName

   EventParameter ::= SEQUENCE
   {
        eventParameterName              Name,

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        value                           Value
   }

   ServiceChangeRequest ::= SEQUENCE
   {
        terminationID                   TerminationIDList,
        serviceChangeParms              ServiceChangeParm,
        ...
   }

   ServiceChangeReply ::= SEQUENCE
   {
        terminationID                   TerminationIDList,
        serviceChangeResult             ServiceChangeResult,
        ...
   }

   -- For ServiceChangeResult, no parameters are mandatory.  Hence the
   -- distinction between ServiceChangeParm and ServiceChangeResParm.

   ServiceChangeResult ::= CHOICE
   {
        errorDescriptor                 ErrorDescriptor,
        serviceChangeResParms           ServiceChangeResParm
   }

   WildcardField ::= OCTET STRING(SIZE(1))

   TerminationID ::= SEQUENCE
   {
        wildcard        SEQUENCE OF WildcardField,
        id              OCTET STRING(SIZE(1..8)),
        ...
   }
   -- See Section A.1 for explanation of wildcarding mechanism.
   -- Termination ID 0xFFFFFFFFFFFFFFFF indicates the ROOT Termination.

   TerminationIDList ::= SEQUENCE OF TerminationID

   MediaDescriptor ::= SEQUENCE
   {

        termStateDescr  TerminationStateDescriptor OPTIONAL,
        streams         CHOICE
                {
                        oneStream       StreamParms,
                        multiStream     SEQUENCE OF StreamDescriptor
                },

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        ...
   }

   StreamDescriptor ::= SEQUENCE
   {
        streamID                        StreamID,
        streamParms                     StreamParms
   }

   StreamParms ::= SEQUENCE
   {
        localControlDescriptor     LocalControlDescriptor OPTIONAL,
        localDescriptor            LocalRemoteDescriptor OPTIONAL,
        remoteDescriptor           LocalRemoteDescriptor OPTIONAL,
        ...
   }

   LocalControlDescriptor ::= SEQUENCE
   {
        streamMode      StreamMode OPTIONAL,
        reserveValue    BOOLEAN,
        reserveGroup    BOOLEAN,
        propertyParms   SEQUENCE OF PropertyParm,
        ...
   }

   StreamMode ::= ENUMERATED
   {
        sendOnly(0),
        recvOnly(1),
        sendRecv(2),
        inactive(3),
        loopBack(4),
                ...
   }

   -- In PropertyParm, value is a SEQUENCE OF octet string.  When sent
   -- by an MGC the interpretation is as follows:
   -- empty sequence means CHOOSE
   -- one element sequence specifies value
   -- If the sublist field is not selected, a longer sequence means
   -- "choose one of the values" (i.e. value1 OR value2 OR ...)
   -- If the sublist field is selected,
   -- a sequence with more than one element encodes the value of a
   -- list-valued property (i.e. value1 AND value2 AND ...).
   -- The relation field may only be selected if the value sequence
   -- has length 1.  It indicates that the MG has to choose a value
   -- for the property. E.g., x > 3 (using the greaterThan

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   -- value for relation) instructs the MG to choose any value larger
   -- than 3 for property x.
   -- The range field may only be selected if the value sequence
   -- has length 2.  It indicates that the MG has to choose a value
   -- in the range between the first octet in the value sequence and
   -- the trailing octet in the value sequence, including the
   -- boundary values.
   -- When sent by the MG, only responses to an AuditCapability request
   -- may contain multiple values, a range, or a relation field.

   PropertyParm ::= SEQUENCE
   {
        name            PkgdName,
        value           SEQUENCE OF OCTET STRING,
        extraInfo       CHOICE
                {
                        relation        Relation,
                        range           BOOLEAN,
                        sublist         BOOLEAN
                } OPTIONAL,
        ...
   }

   Name ::= OCTET STRING(SIZE(2))

   PkgdName ::= OCTET STRING(SIZE(4))
   -- represents Package Name (2 octets) plus Property Name (2 octets)
   -- To wildcard a package use 0xFFFF for first two octets, choose
   -- is not allowed. To reference native property tag specified in
   -- Annex C, use 0x0000 as first two octets.
   -- Wildcarding of Package Name is permitted only if Property Name is
   -- also wildcarded.

   Relation ::= ENUMERATED
   {
        greaterThan(0),
        smallerThan(1),
        unequalTo(2),
        ...
   }

   LocalRemoteDescriptor ::= SEQUENCE
   {
        propGrps        SEQUENCE OF PropertyGroup,
        ...
   }

   PropertyGroup ::= SEQUENCE OF PropertyParm

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   TerminationStateDescriptor ::= SEQUENCE
   {
        propertyParms           SEQUENCE OF PropertyParm,
        eventBufferControl      EventBufferControl OPTIONAL,
        serviceState            ServiceState OPTIONAL,
        ...
   }

   EventBufferControl ::= ENUMERATED
   {
        off(0),
        lockStep(1),
        ...
   }

   ServiceState ::= ENUMERATED
   {
        test(0),
        outOfSvc(1),
        inSvc(2),
         ...
   }

   MuxDescriptor   ::= SEQUENCE
   {
        muxType                 MuxType,
        termList                SEQUENCE OF TerminationID,
        nonStandardData         NonStandardData OPTIONAL,
        ...
   }

   MuxType ::= ENUMERATED
   {
        h221(0),
        h223(1),
        h226(2),
        v76(3),
        ...
   }

   StreamID ::= INTEGER(0..65535)  -- 16 bit unsigned integer

   EventsDescriptor ::= SEQUENCE
   {
        requestID               RequestID,
        eventList               SEQUENCE OF RequestedEvent,
        ...

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   }

   RequestedEvent ::= SEQUENCE
   {
        pkgdName                PkgdName,
        streamID                StreamID OPTIONAL,
        eventAction             RequestedActions OPTIONAL,
        evParList               SEQUENCE OF EventParameter,
        ...
   }

   RequestedActions ::= SEQUENCE
   {
        keepActive              BOOLEAN,
        eventDM                 EventDM OPTIONAL,
        secondEvent             SecondEventsDescriptor OPTIONAL,
        signalsDescriptor       SignalsDescriptor OPTIONAL,
        ...
   }


   EventDM ::= CHOICE
   {    digitMapName    DigitMapName,
        digitMapValue   DigitMapValue
   }

   SecondEventsDescriptor ::= SEQUENCE
   {
        requestID               RequestID,
        eventList               SEQUENCE OF SecondRequestedEvent,
        ...
   }

   SecondRequestedEvent ::= SEQUENCE
   {
        pkgdName                PkgdName,
        streamID                StreamID OPTIONAL,
        eventAction             SecondRequestedActions OPTIONAL,
        evParList               SEQUENCE OF EventParameter,
        ...
   }

   SecondRequestedActions ::= SEQUENCE
   {
        keepActive              BOOLEAN,
        eventDM                 EventDM OPTIONAL,
        signalsDescriptor       SignalsDescriptor OPTIONAL,
        ...

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   }

   EventBufferDescriptor ::= SEQUENCE OF EventSpec

   EventSpec ::= SEQUENCE
   {
        eventName               EventName,
        streamID                StreamID OPTIONAL,
        eventParList            SEQUENCE OF EventParameter,
        ...
   }

   SignalsDescriptor ::= SEQUENCE OF SignalRequest

   SignalRequest ::=CHOICE
   {
        signal          Signal,
        seqSigList      SeqSigList,
        ...
   }

   SeqSigList ::= SEQUENCE
   {
        id              INTEGER(0..65535),
        signalList      SEQUENCE OF Signal
   }

   Signal ::= SEQUENCE
   {
        signalName              SignalName,
        streamID                StreamID OPTIONAL,
        sigType                 SignalType OPTIONAL,
        duration                INTEGER (0..65535) OPTIONAL,
        notifyCompletion        NotifyCompletion OPTIONAL,
        keepActive              BOOLEAN OPTIONAL,
        sigParList              SEQUENCE OF SigParameter,
        ...
   }

   SignalType ::= ENUMERATED
   {
        brief(0),
        onOff(1),
        timeOut(2),
        ...
   }

   SignalName ::= PkgdName

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   NotifyCompletion ::= BIT STRING
   {
        onTimeOut(0), onInterruptByEvent(1),
        onInterruptByNewSignalDescr(2), otherReason(3)
   }

   SigParameter ::= SEQUENCE
   {
        sigParameterName                Name,
        value                           Value
   }

   RequestID ::= INTEGER(0..4294967295)   -- 32 bit unsigned integer

   ModemDescriptor ::= SEQUENCE
   {
        mtl                     SEQUENCE OF ModemType,
        mpl                     SEQUENCE OF PropertyParm,
        nonStandardData         NonStandardData OPTIONAL
   }

   ModemType ::= ENUMERATED
   {
        v18(0),
        v22(1),
        v22bis(2),
        v32(3),
        v32bis(4),
        v34(5),
        v90(6),
        v91(7),
        synchISDN(8),
        ...
   }

   DigitMapDescriptor ::= SEQUENCE
   {
        digitMapName            DigitMapName    OPTIONAL,
        digitMapValue           DigitMapValue   OPTIONAL
   }

   DigitMapName ::= Name

   DigitMapValue ::= SEQUENCE
   {
        startTimer              INTEGER(0..99) OPTIONAL,
        shortTimer              INTEGER(0..99) OPTIONAL,

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        longTimer               INTEGER(0..99) OPTIONAL,
        digitMapBody            IA5String,
        -- See Section A.3 for explanation of digit map syntax
        ...
   }

   ServiceChangeParm ::= SEQUENCE
   {
        serviceChangeMethod     ServiceChangeMethod,
        serviceChangeAddress    ServiceChangeAddress OPTIONAL,
        serviceChangeVersion    INTEGER(0..99) OPTIONAL,
        serviceChangeProfile    ServiceChangeProfile OPTIONAL,
        serviceChangeReason     Value,
        serviceChangeDelay      INTEGER(0..4294967295) OPTIONAL,
                                    -- 32 bit unsigned integer
        serviceChangeMgcId      MId OPTIONAL,
        timeStamp               TimeNotation OPTIONAL,
        nonStandardData         NonStandardData OPTIONAL,
   }

   ServiceChangeAddress ::= CHOICE
   {
        portNumber      INTEGER(0..65535), -- TCP/UDP port number
        ip4Address      IP4Address,
        ip6Address      IP6Address,
        domainName      DomainName,
        deviceName      PathName,
        mtpAddress      OCTET STRING(SIZE(2)),
        ...
   }

   ServiceChangeResParm ::= SEQUENCE
   {
        serviceChangeMgcId      MId OPTIONAL,
        serviceChangeAddress    ServiceChangeAddress OPTIONAL,
        serviceChangeVersion    INTEGER(0..99) OPTIONAL,
        serviceChangeProfile    ServiceChangeProfile OPTIONAL,
        ...
   }

   ServiceChangeMethod ::= ENUMERATED
   {
        failover(0),
        forced(1),
        graceful(2),
        restart(3),
        disconnected(4),
        handOff(5),

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        ...
   }

   ServiceChangeProfile ::= SEQUENCE
   {
        profileName     Name,
        version         INTEGER(0..99)
   }

   PackagesDescriptor ::= SEQUENCE OF PackagesItem

   PackagesItem ::= SEQUENCE
   {
        packageName             Name,
        packageVersion  INTEGER(0..99),
        ...
   }

   StatisticsDescriptor ::= SEQUENCE OF StatisticsParameter

   StatisticsParameter ::= SEQUENCE
   {
        statName                PkgdName,
        statValue               Value
   }

   NonStandardData ::= SEQUENCE
   {
        nonStandardIdentifier   NonStandardIdentifier,
        data                    OCTET STRING
   }

   NonStandardIdentifier                ::= CHOICE
   {
        object                  OBJECT IDENTIFIER,
        h221NonStandard         H221NonStandard,
        experimental            IA5String(SIZE(8)),
    -- first two characters should be "X-" or "X+"
        ...
   }

   H221NonStandard ::= SEQUENCE
   {    t35CountryCode1   INTEGER(0..255),
        t35CountryCode2    INTEGER(0..255), -- country, as per T.35
        t35Extension       INTEGER(0..255), -- assigned nationally
        manufacturerCode   INTEGER(0..65535), -- assigned nationally
        ...
   }

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   TimeNotation ::= SEQUENCE
   {
        date            IA5String(SIZE(8)),  -- yyyymmdd format
        time            IA5String(SIZE(8))  -- hhmmssss format
   }

   Value ::= OCTET STRING


   END

A.3 Digit maps and path names

   From a syntactic viewpoint, digit maps are strings with syntactic
   restrictions imposed upon them.  The syntax of valid digit maps is
   specified in ABNF [RFC 2234].  The syntax for digit maps presented in
   this section is for illustrative purposes only. The definition of
   digitMap in Annex B takes precedence in the case of differences
   between the two.

   digitMap = (digitString / LWSP "(" LWSP digitStringList LWSP ")"
   LWSP)
   digitStringList = digitString *( LWSP "/" LWSP digitString )
   digitString = 1*(digitStringElement)
   digitStringElement = digitPosition [DOT]
   digitPosition = digitMapLetter / digitMapRange
   digitMapRange = ("x" / LWSP "[" LWSP digitLetter LWSP "]" LWSP)
   digitLetter = *((DIGIT "-" DIGIT) /digitMapLetter)
   digitMapLetter = DIGIT               ;digits 0-9
        / %x41-4B / %x61-6B             ;a-k and A-K
        / "L"   / "S"                   ;Inter-event timers
                                        ;(long, short)
        / "Z"                           ;Long duration event
   DOT = %x2E ; "."
   LWSP = *(WSP / COMMENT / EOL)
   WSP = SP / HTAB
   COMMENT = ";" *(SafeChar / RestChar / WSP) EOL
   EOL = (CR [LF]) / LF
   SP = %x20
   HTAB = %x09
   CR = %x0D
   LF = %x0A
   SafeChar = DIGIT / ALPHA / "+" / "-" / "&" / "!" / "_" / "/" /
    "'" / "?" / "@" / "^" / "`" / "~" / "*" / "$" / "\" /
   "(" / ")" / "%" / "."
   RestChar = ";" / "[" / "]" / "{" / "}" / ":" / "," / "#" /
                "<" / ">" / "=" / %x22

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   DIGIT = %x30-39                      ; digits 0 through 9
   ALPHA = %x41-5A / %x61-7A    ; A-Z, a-z
   A path name is also a string with syntactic restrictions imposed
   upon it.  The ABNF production defining it is copied from Annex B.

   PathName = NAME *(["/"] ["*"] ["@"] (ALPHA / DIGIT)) ["*"]
   NAME = ALPHA *63(ALPHA / DIGIT / "_" )

ANNEX B TEXT ENCODING OF THE PROTOCOL (NORMATIVE)

B.1 Coding of wildcards

   In a text encoding of the protocol, while TerminationIDs are
   arbitrary, by judicious choice of names, the wildcard character, "*"
   may be made more useful.  When the wildcard character is encountered,
   it will "match" all TerminationIDs having the same previous and
   following characters (if appropriate).  For example, if there were
   TerminationIDs of R13/3/1, R13/3/2 and R13/3/3, the TerminationID
   R13/3/* would match all of them.  There are some circumstances where
   ALL Terminations must be referred to.  The TerminationID "*"
   suffices, and is referred to as ALL. The CHOOSE TerminationID "$" may
   be used to signal to the MG that it has to create an ephemeral
   Termination or select an idle physical Termination.

B.2 ABNF specification

   The protocol syntax is presented in ABNF according to RFC2234.

   ; Boolean values, indicated in the text as True and False, are
   ; encoded as "On" and "Off", respectively, in the ABNF.

   megacoMessage        = LWSP [authenticationHeader SEP ] message

   authenticationHeader = AuthToken EQUAL SecurityParmIndex COLON
                          SequenceNum COLON AuthData

   SecurityParmIndex    = "0x" 8(HEXDIG)
   SequenceNum          = "0x" 8(HEXDIG)
   AuthData             = "0x" 24*64(HEXDIG)

   message    = MegacopToken SLASH Version SEP mId SEP messageBody
   ; The version of the protocol defined here is equal to 1.

   messageBody          = ( errorDescriptor / transactionList )

   transactionList      = 1*( transactionRequest / transactionReply /
                          transactionPending / transactionResponseAck )
   ;Use of response acks is dependent on underlying transport

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   transactionPending   = PendingToken EQUAL TransactionID LBRKT RBRKT

   transactionResponseAck = ResponseAckToken LBRKT transactionAck
                                        *(COMMA transactionAck) RBRKT
   transactionAck = transactionID / (transactionID "-" transactionID)

   transactionRequest   = TransToken EQUAL TransactionID LBRKT
                          actionRequest *(COMMA actionRequest) RBRKT

   actionRequest        = CtxToken EQUAL ContextID LBRKT ((
                          contextRequest [COMMA  commandRequestList])
                          / commandRequestList) RBRKT

   contextRequest          = ((contextProperties [COMMA contextAudit])
                           / contextAudit)

   contextProperties    = contextProperty *(COMMA contextProperty)

   ; at-most-once
   contextProperty  = (topologyDescriptor / priority / EmergencyToken)

   contextAudit    = ContextAuditToken LBRKT
                          contextAuditProperties *(COMMA
                          contextAuditProperties) RBRKT

   ; at-most-once
   contextAuditProperties = ( TopologyToken / EmergencyToken /
                              PriorityToken )

   commandRequestList= ["O-"] commandRequest *(COMMA ["O-"]
   commandRequest)

   commandRequest     = ( ammRequest / subtractRequest / auditRequest
                           / notifyRequest / serviceChangeRequest)

   transactionReply     = ReplyToken EQUAL TransactionID LBRKT
                           [ ImmAckRequiredToken COMMA]
                          ( errorDescriptor / actionReplyList ) RBRKT

   actionReplyList      = actionReply *(COMMA actionReply )

   actionReply          = CtxToken EQUAL ContextID LBRKT
                          ( errorDescriptor / commandReply ) RBRKT

   commandReply       = (( contextProperties [COMMA commandReplyList] )
                           / commandReplyList )

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   commandReplyList     = commandReplys *(COMMA commandReplys )

   commandReplys        = (serviceChangeReply / auditReply / ammsReply
                           / notifyReply )

   ;Add Move and Modify have the same request parameters
   ammRequest           = (AddToken / MoveToken / ModifyToken ) EQUAL
                          TerminationID [LBRKT ammParameter *(COMMA
                          ammParameter) RBRKT]

   ;at-most-once
   ammParameter         = (mediaDescriptor / modemDescriptor /
                           muxDescriptor / eventsDescriptor /
                           signalsDescriptor / digitMapDescriptor /
                           eventBufferDescriptor / auditDescriptor)

   ammsReply            = (AddToken / MoveToken / ModifyToken /
                           SubtractToken ) EQUAL TerminationID [ LBRKT
                           terminationAudit RBRKT ]

   subtractRequest      =  ["W-"] SubtractToken EQUAL TerminationID
                           [ LBRKT auditDescriptor RBRKT]

   auditRequest         = ["W-"] (AuditValueToken / AuditCapToken )
                        EQUAL TerminationID LBRKT auditDescriptor RBRKT

   auditReply           = (AuditValueToken / AuditCapToken )
                          ( contextTerminationAudit  / auditOther)

   auditOther           = EQUAL TerminationID LBRKT
                          terminationAudit RBRKT

   terminationAudit     = auditReturnParameter *(COMMA
                        auditReturnParameter)

   contextTerminationAudit = EQUAL CtxToken ( terminationIDList /
                          LBRKT errorDescriptor RBRKT )

   auditReturnParameter = (mediaDescriptor / modemDescriptor /
                           muxDescriptor / eventsDescriptor /
                           signalsDescriptor / digitMapDescriptor /
                     observedEventsDescriptor / eventBufferDescriptor /
                           statisticsDescriptor / packagesDescriptor /
                            errorDescriptor / auditItem )

   auditDescriptor      = AuditToken LBRKT [ auditItem
                          *(COMMA auditItem) ] RBRKT

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   notifyRequest        = NotifyToken EQUAL TerminationID
                          LBRKT ( observedEventsDescriptor
                                [ COMMA errorDescriptor ] ) RBRKT

   notifyReply          = NotifyToken EQUAL TerminationID
                          [ LBRKT errorDescriptor RBRKT ]

   serviceChangeRequest = ServiceChangeToken EQUAL TerminationID
                          LBRKT serviceChangeDescriptor RBRKT

   serviceChangeReply   = ServiceChangeToken EQUAL TerminationID
                          [LBRKT (errorDescriptor /
                          serviceChangeReplyDescriptor) RBRKT]

   errorDescriptor   = ErrorToken EQUAL ErrorCode
                       LBRKT [quotedString] RBRKT

   ErrorCode            = 1*4(DIGIT) ; could be extended

   TransactionID        = UINT32

   mId                  = (( domainAddress / domainName )
                          [":" portNumber]) / mtpAddress / deviceName

   ; ABNF allows two or more consecutive "." although it is meaningless
   ; in a domain name.
   domainName           = "<" (ALPHA / DIGIT) *63(ALPHA / DIGIT / "-" /
                          ".") ">"
   deviceName           = pathNAME

   ;The values 0x0, 0xFFFFFFFE and 0xFFFFFFFF are reserved.
   ContextID            = (UINT32 / "*" / "-" / "$")

   domainAddress        = "[" (IPv4address / IPv6address) "]"
   ;RFC2373 contains the definition of IP6Addresses.
   IPv6address          = hexpart [ ":" IPv4address ]
   IPv4address          = V4hex DOT V4hex DOT V4hex DOT V4hex
   V4hex                = 1*3(DIGIT) ; "0".."225"
   ; this production, while occurring in RFC2373, is not referenced
   ; IPv6prefix           = hexpart SLASH 1*2DIGIT
   hexpart          = hexseq "::" [ hexseq ] / "::" [ hexseq ] / hexseq
   hexseq               = hex4 *( ":" hex4)
   hex4                 = 1*4HEXDIG

   portNumber           = UINT16

   ; An mtp address is two octets long

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   mtpAddress           = MTPToken LBRKT octetString RBRKT

   terminationIDList    = LBRKT TerminationID *(COMMA TerminationID)
   RBRKT

   ; Total length of pathNAME must not exceed 64 chars.
   pathNAME        = ["*"] NAME *("/" / "*"/ ALPHA / DIGIT /"_" / "$" )
                          ["@" pathDomainName ]

   ; ABNF allows two or more consecutive "." although it is meaningless
   ; in a path domain name.
   pathDomainName       = (ALPHA / DIGIT / "*" )
                          *63(ALPHA / DIGIT / "-" / "*" / ".")

   TerminationID        = "ROOT" / pathNAME / "$" / "*"

   mediaDescriptor = MediaToken LBRKT mediaParm *(COMMA mediaParm)
                        RBRKT

   ; at-most-once per item
   ; and either streamParm or streamDescriptor but not both
   mediaParm            = (streamParm / streamDescriptor /
                           terminationStateDescriptor)

   ; at-most-once
   streamParm           = ( localDescriptor / remoteDescriptor /
                           localControlDescriptor )

   streamDescriptor     = StreamToken EQUAL StreamID LBRKT streamParm
                          *(COMMA streamParm) RBRKT

   localControlDescriptor = LocalControlToken LBRKT localParm
                            *(COMMA localParm) RBRKT

   ; at-most-once per item
   localParm            = ( streamMode / propertyParm /
   reservedValueMode
        / reservedGroupMode )

   reservedValueMode       = ReservedValueToken EQUAL ( "ON" / "OFF" )
   reservedGroupMode       = ReservedGroupToken EQUAL ( "ON" / "OFF" )

   streamMode           = ModeToken EQUAL streamModes

   streamModes          = (SendonlyToken / RecvonlyToken /
   SendrecvToken /
                          InactiveToken / LoopbackToken )

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   propertyParm         = pkgdName parmValue
   parmValue            = (EQUAL alternativeValue/ INEQUAL VALUE)
   alternativeValue     = ( VALUE
                          / LSBRKT VALUE *(COMMA VALUE) RSBRKT
                            ; sublist (i.e. A AND B AND ...)
                          / LBRKT VALUE *(COMMA VALUE) RBRKT
                            ; alternatives (i.e. A OR B OR ...)
                          / LSBRKT VALUE COLON VALUE RSBRKT )
                            ; range
   INEQUAL              = LWSP (">" / "<" / "#" ) LWSP
   LSBRKT               = LWSP "[" LWSP
   RSBRKT               = LWSP "]" LWSP

   localDescriptor      = LocalToken LBRKT octetString RBRKT

   remoteDescriptor     = RemoteToken LBRKT octetString RBRKT

   eventBufferDescriptor= EventBufferToken LBRKT eventSpec
                          *( COMMA eventSpec ) RBRKT
   eventSpec            = pkgdName [ LBRKT eventSpecParameter
                            *(COMMA eventSpecParameter) RBRKT ]
   eventSpecParameter   = (eventStream / eventOther)

   eventBufferControl     = BufferToken EQUAL ( "OFF" / LockStepToken )

   terminationStateDescriptor = TerminationStateToken LBRKT
               terminationStateParm *( COMMA terminationStateParm )
   RBRKT

   ; at-most-once per item
   terminationStateParm =(propertyParm / serviceStates /
   eventBufferControl )

   serviceStates        = ServiceStatesToken EQUAL ( TestToken /
                          OutOfSvcToken / InSvcToken )

   muxDescriptor        = MuxToken EQUAL MuxType  terminationIDList

   MuxType              = ( H221Token / H223Token / H226Token /
                       V76Token / extensionParameter )

   StreamID             = UINT16
   pkgdName             = (PackageName SLASH ItemID) ;specific item
                    / (PackageName SLASH "*") ;all events in package
                    / ("*" SLASH "*") ; all events supported by the MG
   PackageName          = NAME
   ItemID               = NAME

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   eventsDescriptor     = EventsToken EQUAL RequestID LBRKT
                         requestedEvent *( COMMA requestedEvent ) RBRKT

   requestedEvent       = pkgdName [ LBRKT eventParameter
                          *( COMMA eventParameter ) RBRKT ]

   ; at-most-once each of KeepActiveToken , eventDM and eventStream
   ;at most one of either embedWithSig or embedNoSig but not both
   ;KeepActiveToken and embedWithSig must not both be present
   eventParameter       = ( embedWithSig / embedNoSig / KeepActiveToken
                           /eventDM / eventStream / eventOther )

   embedWithSig         = EmbedToken LBRKT signalsDescriptor
                             [COMMA embedFirst ] RBRKT
   embedNoSig           = EmbedToken LBRKT embedFirst RBRKT

   ; at-most-once of each
   embedFirst      = EventsToken EQUAL RequestID LBRKT
               secondRequestedEvent *(COMMA secondRequestedEvent) RBRKT

   secondRequestedEvent = pkgdName [ LBRKT secondEventParameter
                          *( COMMA secondEventParameter ) RBRKT ]

   ; at-most-once each of embedSig , KeepActiveToken, eventDM or
   ; eventStream
   ; KeepActiveToken and embedSig must not both be present
   secondEventParameter = ( EmbedSig / KeepActiveToken / eventDM /
                            eventStream / eventOther )

   embedSig  = EmbedToken LBRKT signalsDescriptor RBRKT

   eventStream          = StreamToken EQUAL StreamID

   eventOther           = eventParameterName parmValue

   eventParameterName   = NAME

   eventDM              = DigitMapToken ((EQUAL digitMapName ) /
                          (LBRKT digitMapValue RBRKT ))

   signalsDescriptor    = SignalsToken LBRKT [ signalParm
                          *(COMMA signalParm)] RBRKT

   signalParm           = signalList / signalRequest

   signalRequest        = signalName [ LBRKT sigParameter
                          *(COMMA sigParameter) RBRKT ]

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   signalList           = SignalListToken EQUAL signalListId LBRKT
                          signalListParm *(COMMA signalListParm) RBRKT

   signalListId         = UINT16

   ;exactly once signalType, at most once duration and every signal
   ;parameter
   signalListParm       = signalRequest

   signalName           = pkgdName
   ;at-most-once sigStream, at-most-once sigSignalType,
   ;at-most-once sigDuration, every signalParameterName at most once
   sigParameter    = sigStream / sigSignalType / sigDuration / sigOther
                   / notifyCompletion / KeepActiveToken
   sigStream            = StreamToken EQUAL StreamID
   sigOther             = sigParameterName parmValue
   sigParameterName     = NAME
   sigSignalType        = SignalTypeToken EQUAL signalType
   signalType           = (OnOffToken / TimeOutToken / BriefToken)
   sigDuration          = DurationToken EQUAL UINT16
   notifyCompletion     = NotifyCompletionToken EQUAL (LBRKT
                   notificationReason *(COMMA notificationReason) RBRKT

   notificationReason   = ( TimeOutToken / InterruptByEventToken
                                / InterruptByNewSignalsDescrToken
                                / OtherReasonToken )

   observedEventsDescriptor = ObservedEventsToken EQUAL RequestID
                      LBRKT observedEvent *(COMMA observedEvent) RBRKT

   ;time per event, because it might be buffered
   observedEvent        = [ TimeStamp LWSP COLON] LWSP
                          pkgdName [ LBRKT observedEventParameter
                          *(COMMA observedEventParameter) RBRKT ]

   ;at-most-once eventStream, every eventParameterName at most once
   observedEventParameter = eventStream / eventOther

   RequestID            = UINT32

   modemDescriptor      = ModemToken (( EQUAL modemType) /
                          (LSBRKT modemType *(COMMA modemType) RSBRKT))
                          [ LBRKT NAME parmValue
                         *(COMMA NAME parmValue) RBRKT ]

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   ; at-most-once
   modemType            = (V32bisToken / V22bisToken / V18Token /
                           V22Token / V32Token / V34Token / V90Token /
                        V91Token / SynchISDNToken / extensionParameter)

   digitMapDescriptor   = DigitMapToken EQUAL
                          ( ( LBRKT digitMapValue RBRKT )
                       / (digitMapName [ LBRKT digitMapValue RBRKT ]) )
   digitMapName       = NAME
   digitMapValue      = ["T" COLON Timer COMMA] ["S" COLON Timer COMMA]
                          ["L" COLON Timer COMMA] digitMap
   Timer              = 1*2DIGIT
   digitMap =
        digitString / LWSP "(" LWSP digitStringList LWSP ")" LWSP
   digitStringList      = digitString *( LWSP "|" LWSP digitString )
   digitString          = 1*(digitStringElement)
   digitStringElement   = digitPosition [DOT]
   digitPosition        = digitMapLetter / digitMapRange
   digitMapRange      = ("x" / LWSP "[" LWSP digitLetter LWSP "]" LWSP)
   digitLetter          = *((DIGIT "-" DIGIT ) / digitMapLetter)
   digitMapLetter       = DIGIT   ;Basic event symbols
                   / %x41-4B / %x61-6B ; a-k, A-K
                   / "L" / "S"   ;Inter-event timers (long, short)
                   / "Z"         ;Long duration modifier

   ;at-most-once, and DigitMapToken and PackagesToken are not allowed
   ;in AuditCapabilities command

   auditItem            = ( MuxToken / ModemToken / MediaToken /
                           SignalsToken / EventBufferToken /
                           DigitMapToken / StatsToken / EventsToken /
                           ObservedEventsToken / PackagesToken )

   serviceChangeDescriptor = ServicesToken LBRKT serviceChangeParm
                            *(COMMA serviceChangeParm) RBRKT

   serviceChangeParm    = (serviceChangeMethod / serviceChangeReason /
                          serviceChangeDelay / serviceChangeAddress /
                         serviceChangeProfile / extension / TimeStamp /
                          serviceChangeMgcId / serviceChangeVersion )

   serviceChangeReplyDescriptor = ServicesToken LBRKT
                       servChgReplyParm *(COMMA servChgReplyParm) RBRKT

   ;at-most-once. Version is REQUIRED on first ServiceChange response
   servChgReplyParm     = (serviceChangeAddress / serviceChangeMgcId /
                          serviceChangeProfile / serviceChangeVersion )
   serviceChangeMethod  = MethodToken EQUAL (FailoverToken /

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                          ForcedToken / GracefulToken / RestartToken /
                          DisconnectedToken / HandOffToken /
                          extensionParameter)

   serviceChangeReason  = ReasonToken  EQUAL VALUE
   serviceChangeDelay   = DelayToken   EQUAL UINT32
   serviceChangeAddress = ServiceChangeAddressToken EQUAL VALUE
   serviceChangeMgcId   = MgcIdToken   EQUAL mId
   serviceChangeProfile = ProfileToken EQUAL NAME SLASH Version
   serviceChangeVersion = VersionToken EQUAL Version
   extension            = extensionParameter parmValue

   packagesDescriptor   = PackagesToken LBRKT packagesItem
                          *(COMMA packagesItem) RBRKT

   Version              = 1*2(DIGIT)
   packagesItem         = NAME "-" UINT16

   TimeStamp            = Date "T" Time ; per ISO 8601:1988
   ; Date = yyyymmdd
   Date                 = 8(DIGIT)
   ; Time = hhmmssss
   Time                 = 8(DIGIT)
   statisticsDescriptor = StatsToken LBRKT statisticsParameter
                         *(COMMA statisticsParameter ) RBRKT

   ;at-most-once per item
   statisticsParameter  = pkgdName EQUAL VALUE

   topologyDescriptor   = TopologyToken LBRKT terminationA COMMA
                          terminationB COMMA topologyDirection RBRKT
   terminationA         = TerminationID
   terminationB         = TerminationID
   topologyDirection    = BothwayToken / IsolateToken / OnewayToken

   priority             = PriorityToken EQUAL UINT16

   extensionParameter   = "X"  ("-" / "+") 1*6(ALPHA / DIGIT)

   ; octetString is used to describe SDP defined in RFC2327.
   ; Caution should be taken if CRLF in RFC2327 is used.
   ; To be safe, use EOL in this ABNF.
   ; Whenever "}" appears in SDP, it is escaped by "\", e.g., "\}"
   octetString          = *(nonEscapeChar)
   nonEscapeChar        = ( "\}" / %x01-7C / %x7E-FF )
   quotedString         = DQUOTE 1*(SafeChar / RestChar/ WSP) DQUOTE

   UINT16               = 1*5(DIGIT)  ; %x0-FFFF

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   UINT32               = 1*10(DIGIT) ; %x0-FFFFFFFF

   NAME                 = ALPHA *63(ALPHA / DIGIT / "_" )
   VALUE                = quotedString / 1*(SafeChar)
   SafeChar             = DIGIT / ALPHA / "+" / "-" / "&" /
                          "!" / "_" / "/" / "'" / "?" / "@" /
                          "^" / "`" / "~" / "*" / "$" / "\" /
                          "(" / ")" / "%" / "|" / "."

   EQUAL                = LWSP %x3D LWSP ; "="
   COLON                = %x3A           ; ":"
   LBRKT                = LWSP %x7B LWSP ; "{"
   RBRKT                = LWSP %x7D LWSP ; "}"
   COMMA                = LWSP %x2C LWSP ; ","
   DOT                  = %x2E           ; "."
   SLASH                = %x2F           ; "/"
   ALPHA                = %x41-5A / %x61-7A ; A-Z / a-z
   DIGIT                = %x30-39         ; 0-9
   DQUOTE               = %x22            ; " (Double Quote)
   HEXDIG               = ( DIGIT / "A" / "B" / "C" / "D" / "E" / "F" )
   SP                   = %x20        ; space
   HTAB                 = %x09        ; horizontal tab
   CR                   = %x0D        ; Carriage return
   LF                   = %x0A        ; linefeed
   LWSP                 = *( WSP / COMMENT / EOL )
   EOL                  = (CR [LF] / LF )
   WSP                  = SP / HTAB ; white space
   SEP                  = ( WSP / EOL / COMMENT) LWSP
   COMMENT              = ";" *(SafeChar/ RestChar / WSP / %x22) EOL
   RestChar             = ";" / "[" / "]" / "{" / "}" / ":" / "," / "#"
   /
                          "<" / ">" / "="


   AddToken                   = ("Add"                   / "A")
   AuditToken                 = ("Audit"                 / "AT")
   AuditCapToken              = ("AuditCapability"       / "AC")
   AuditValueToken            = ("AuditValue"            / "AV")
   AuthToken                  = ("Authentication"        / "AU")
   BothwayToken               = ("Bothway"               / "BW")
   BriefToken                 = ("Brief"                 / "BR")
   BufferToken                = ("Buffer"                / "BF")
   CtxToken                   = ("Context"               / "C")
   ContextAuditToken          = ("ContextAudit"          / "CA")
   DigitMapToken              = ("DigitMap"              / "DM")
   DisconnectedToken          = ("Disconnected"          / "DC")
   DelayToken                 = ("Delay"                 / "DL")
   DurationToken              = ("Duration"              / "DR")

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   EmbedToken                 = ("Embed"                 / "EB")
   EmergencyToken             = ("Emergency"             / "EM")
   ErrorToken                 = ("Error"                 / "ER")
   EventBufferToken           = ("EventBuffer"           / "EB")
   EventsToken                = ("Events"                / "E")
   FailoverToken              = ("Failover"              / "FL")
   ForcedToken                = ("Forced"                / "FO")
   GracefulToken              = ("Graceful"              / "GR")
   H221Token                  = ("H221" )
   H223Token                  = ("H223" )
   H226Token                  = ("H226" )
   HandOffToken               = ("HandOff"               / "HO")
   ImmAckRequiredToken        = ("ImmAckRequired"        / "IA")
   InactiveToken              = ("Inactive"              / "IN")
   IsolateToken               = ("Isolate"               / "IS")
   InSvcToken                 = ("InService"             / "IV")
   InterruptByEventToken      = ("IntByEvent"           / "IBE")
   InterruptByNewSignalsDescrToken
                              = ("IntBySigDescr"        / "IBS")
   KeepActiveToken            = ("KeepActive"            / "KA")
   LocalToken                 = ("Local"                 / "L")
   LocalControlToken          = ("LocalControl"          / "O")
   LockStepToken              = ("LockStep"              / "SP")
   LoopbackToken              = ("Loopback"              / "LB")
   MediaToken                 = ("Media"                 / "M")
   MegacopToken               = ("MEGACO"                / "!")
   MethodToken                = ("Method"                / "MT")
   MgcIdToken                 = ("MgcIdToTry"            / "MG")
   ModeToken                  = ("Mode"                  / "MO")
   ModifyToken                = ("Modify"                / "MF")
   ModemToken                 = ("Modem"                 / "MD")
   MoveToken                  = ("Move"                  / "MV")
   MTPToken                   = ("MTP")
   MuxToken                   = ("Mux"                   / "MX")
   NotifyToken                = ("Notify"                / "N")
   NotifyCompletionToken      = ("NotifyCompletion"      / "NC")
   ObservedEventsToken        = ("ObservedEvents"        / "OE")
   OnewayToken                = ("Oneway"                / "OW")
   OnOffToken                 = ("OnOff"                 / "OO")
   OtherReasonToken           = ("OtherReason"           / "OR")
   OutOfSvcToken              = ("OutOfService"          / "OS")
   PackagesToken              = ("Packages"              / "PG")
   PendingToken               = ("Pending"               / "PN")
   PriorityToken              = ("Priority"              / "PR")
   ProfileToken               = ("Profile"               / "PF")
   ReasonToken                = ("Reason"                / "RE")
   RecvonlyToken              = ("ReceiveOnly"           / "RC")
   ReplyToken                 = ("Reply"                 / "P")

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   RestartToken               = ("Restart"               / "RS")
   RemoteToken                = ("Remote"                / "R")
   ReservedGroupToken         = ("ReservedGroup"         / "RG")
   ReservedValueToken         = ("ReservedValue"         / "RV")
   SendonlyToken              = ("SendOnly"              / "SO")
   SendrecvToken              = ("SendReceive"           / "SR")
   ServicesToken              = ("Services"              / "SV")
   ServiceStatesToken         = ("ServiceStates"         / "SI")
   ServiceChangeToken         = ("ServiceChange"         / "SC")
   ServiceChangeAddressToken  = ("ServiceChangeAddress"  / "AD")
   SignalListToken            = ("SignalList"            / "SL")
   SignalsToken               = ("Signals"               / "SG")
   SignalTypeToken            = ("SignalType"            / "SY")
   StatsToken                 = ("Statistics"            / "SA")
   StreamToken                = ("Stream"                / "ST")
   SubtractToken              = ("Subtract"              / "S")
   SynchISDNToken             = ("SynchISDN"             / "SN")
   TerminationStateToken      = ("TerminationState"      / "TS")
   TestToken                  = ("Test"                  / "TE")
   TimeOutToken               = ("TimeOut"               / "TO")
   TopologyToken              = ("Topology"              / "TP")
   TransToken                 = ("Transaction"           / "T")
   ResponseAckToken           = ("TransactionResponseAck"/ "K")
   V18Token                   = ("V18")
   V22Token                   = ("V22")
   V22bisToken                = ("V22b")
   V32Token                   = ("V32")
   V32bisToken                = ("V32b")
   V34Token                   = ("V34")
   V76Token                   = ("V76")
   V90Token                   = ("V90")
   V91Token                   = ("V91")
   VersionToken               = ("Version"               / "V")



(page 112 continued on part 5)

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