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rfc:rfc3624

Network Working Group B. Foster Request for Comments: 3624 D. Auerbach Category: Informational F. Andreasen

                                                         Cisco Systems
                                                         November 2003
   The Media Gateway Control Protocol (MGCP) Bulk Audit Package

Status of this Memo

 This memo provides information for the Internet community.  It does
 not specify an Internet standard of any kind.  Distribution of this
 memo is unlimited.

Copyright Notice

 Copyright (C) The Internet Society (2003).  All Rights Reserved.

IESG Note

 This document is being published for the information of the
 community.  It describes a non-IETF protocol that is currently being
 deployed in a number of products.  Implementers should be aware of
 RFC 3015, which was developed in the IETF Megaco Working Group and
 the ITU-T SG16, and which is considered by the IETF and the ITU-T to
 be the standards-based (including reviewed security considerations)
 way to meet the needs that MGCP was designed to address.

Abstract

 The base Media Gateway Control Protocol (MGCP) includes audit
 commands that only allow a Call Agent to audit endpoint and/or
 connection state one endpoint at a time.  This document describes a
 new MGCP package for bulk auditing of a group of gateway endpoints.
 It allows a Call Agent to determine the endpoint naming convention,
 the list of instantiated endpoints as well connection and endpoint
 state for the group of endpoints.

Foster, et al. Informational [Page 1] RFC 3624 MGCP Bulk Audit Package November 2003

Table of Contents

 1.  Introduction. . . . . . . . . . . . . . . . . . . . . . . . .   2
 2.  Bulk Audit Package. . . . . . . . . . . . . . . . . . . . . .   2
     2.1.  Package Definition. . . . . . . . . . . . . . . . . . .   2
           2.1.1. Package Parameters . . . . . . . . . . . . . . .   3
           2.1.2. Bulk Auditing of Non-persistent Virtual
                  Endpoints. . . . . . . . . . . . . . . . . . . .  11
           2.1.3. Package Specific Return Codes. . . . . . . . . .  12
     2.2.  Examples of Package Use . . . . . . . . . . . . . . . .  13
           2.2.1. Endpoint List. . . . . . . . . . . . . . . . . .  13
           2.2.2. Connection Count List. . . . . . . . . . . . . .  13
           2.2.3. Connection Mode List . . . . . . . . . . . . . .  15
           2.2.4. Endpoint State . . . . . . . . . . . . . . . . .  15
 3.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  17
 4.  Security Considerations . . . . . . . . . . . . . . . . . . .  17
 5.  References. . . . . . . . . . . . . . . . . . . . . . . . . .  18
 6.  Authors' Addresses. . . . . . . . . . . . . . . . . . . . . .  18
 7.  Full Copyright Statement. . . . . . . . . . . . . . . . . . .  19

1. Introduction

 The reader is assumed to be familiar with the base MGCP protocol [3].
 The base Media Gateway Control Protocol (MGCP) [3] includes audit
 commands that only allow a Call Agent to audit an endpoint and/or a
 connection state, one endpoint at a time.  This document describes a
 new MGCP package for bulk auditing of a group of gateway endpoints.
 It allows a Call Agent to determine the endpoint naming convention,
 to determine the list of instantiated endpoints, and to determine the
 connection and endpoint state for the group of endpoints.  This is
 particularly important in fail-over situations in which there are
 gateways that have large numbers of endpoints.
 Conventions Used in this Document
 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
 document are to be interpreted as described in RFC 2119 [2].

2. Bulk Audit Package

2.1. Package Definition

 Package Name: BA
 Package Version: 0

Foster, et al. Informational [Page 2] RFC 3624 MGCP Bulk Audit Package November 2003

 Package Description: This package provides the Call Agent the ability
 to audit and obtain high-level view of endpoint and connection state
 for a group of endpoints in a gateway.

2.1.1. Package Parameters

 A new BulkRequestedInfo parameter is defined for use in the
 AuditEndpoint command.  The parameter can be used to request a
 compact list of EndpointIds or to request a high level view of
 endpoint or connection state for a group of endpoints as defined
 below:
    ReturnCode,
    [EndPointNameList,]
    [InstantiatedEndpointList,]
    [ConnectionCountList,]
    [ConnectionModeList,]
    [EndpointStateList,]
    [NextEndpointName,]
    [ReportedEndpointList]
    <-- AuditEndPoint(EndpointId,
                        [StartEndpointName,]
                        [MaxNumEndpoints,]
                        [BulkRequestedInfo])
 Unlike the normal RequestedInfo parameter in the base MGCP
 specification, the BulkRequestedInfo parameter associated with the
 Bulk Audits package can be used with "all-of" wildcards for auditing
 a collection of endpoints.  However, it is not an error to specify an
 EndpointId without wildcards.
 The following sub-sections describe the parameters associated with
 the Bulk Audit Command in detail.  Sections 2.1.1.1 and 2.1.1.2
 describe the parameters that can be included with a request and
 sections 2.1.1.3 to 2.1.1.8 describe return parameters.

2.1.1.1. StartEndpointName and MaxNumEndpoints Parameters

 Because wild-carding may not be sufficient to qualify the endpoints
 of interest, further qualification can be provided by including a
 StartEndpointName (the first endpoint of interest) and
 MaxNumEndPoints (the maximum number of endpoints of interest).  These
 parameters are described according to the following Augmented BNF
 (ABNF) Syntax (refer to RFC 2234 for ABNF syntax definitions [1]):
    "BA/SE" ":" 0*WSP LocalEndpointName
    "BA/NU" ":" 0*WSP MaxNumEndpoints

Foster, et al. Informational [Page 3] RFC 3624 MGCP Bulk Audit Package November 2003

 where MaxNumEndpoints is the decimal number of endpoints with a value
 in the range 1 to 65535.  The MaxNumEndpoints parameter SHOULD only
 be included when requesting an audit for an EndpointStateList and/or
 ConnectionCountList.  If included in a request for the
 EndPointNameList or InstantiatedEndpointList, it MAY be ignored.
 Note that only the LocalEndpointName (see ABNF grammar in [3]) is
 provided in request and response parameter lines for this package
 rather than the full EndpointName.  This is done for the sake of
 compactness, i.e., the domain name portion is left out since it is
 already available in the command line portion of a given request.
 If the list of endpoints defined by the StartEndpointName and
 MaxNumEndPoints is outside the range designated by the wild-carding,
 a report will only be returned for endpoints up to those specified
 within the wild-card range.

2.1.1.2. BulkRequestedInfo Parameter

 The BulkRequestedInfo parameter line is described according to the
 following ABNF syntax definitions:
    BulkRequestedInfo = "BA/F:" 0*WSP
           *( EndpointOrInstantList *("," EndpointOrInstantList))
         / *( EndpointOrConnState *("," EndpointOrConnState))
    EndpointOrConnState = "BA/C" / "BA/M" /  EndpointStateParam
    EndpointOrInstantList = "BA/Z" / "BA/X"
    EndpointStateParam = "BA/S" "(" StateType
                                       0*("," 0*(WSP) StateType)")"
    StateType = "I" / "D" / "N" / "S" / "H"
 where the BulkRequestedInfo parameters have the following meaning:
  • "BA/Z" is a request to return EndPointNameList
  • "BA/X" is a request to return InstantiatedEndpointList
  • "BA/C" is a request to return the ConnectionCountList
  • "BA/M" is a request to return the ConnectionModeList
  • "BA/S" is a request to return the EndpointStateList
 Each of the parameters can be provided at most once in the
 BulkRequestedInfo.

Foster, et al. Informational [Page 4] RFC 3624 MGCP Bulk Audit Package November 2003

 EndpointStateParam Parameter:
 As indicated in the above ABNF, the EndpointStateParam parameter is
 itself parameterized with one or more StateType parameters that
 define the conditions to be evaluated for the endpoint:
  • "I" - the endpoint is in-service,
  • "D" - the endpoint is disconnected (see sections 4.3 and 4.4.7 of

[3] for a discussion on disconnected endpoints),

  • "N" - the endpoint is in the notification state,
  • "L" - the endpoint is in lockstep state (i.e., waiting for an RQNT

after a response to a NTFY has occurred while in lockstep mode)

  • "S" - there is an active on-off (OO) or timeout (TO) signal on the

endpoint,

  • "H" - the endpoint is in some state other than "idle". The

meaning of this last parameter depends on the type of endpoint:

  • The parameter has no meaning for endpoints that only provide

bearer services (with no state that the endpoint is aware of).

       In this case, the condition is always evaluated to false
       (corresponding to "idle").
    *  For endpoints that have a state machine associated with them
       (such as a CAS endpoint), the endpoint MUST be in some state
       other than the "idle" state in order for the condition to be
       evaluated as true.
    *  In the case where the endpoint has hook-state associated with
       it, the hook-state MUST be off-hook.  In the case of digital
       channel associated signaling (CAS) connections, hook-state may
       be provided in either direction.  If the hook-state in either
       direction is off-hook, the endpoint is considered non-idle,
       i.e., the condition is satisfied.
 The list of StateTypes may be extended in the future.  If an unknown
 StateType is encountered, the command MUST be rejected with error
 code 803 (i.e., "unsupported StateType").
 The report, provided as a result of this request, yields an
 indication of either "True", "False", or "Out of Service" for each
 endpoint.  If the endpoint is in-service and any one of the criteria
 holds true, then the report for the endpoint will evaluate to "True".
 A "False" indication will only be reported if the endpoint is in-
 service and all criteria evaluate to false.  The report thus provides
 the logical "OR" function over the conditions audited for endpoints
 in-service.  Irrespective of the state being audited, an "Out of
 Service" indication will always be reported if the endpoint is
 considered out-of-service.

Foster, et al. Informational [Page 5] RFC 3624 MGCP Bulk Audit Package November 2003

 Note that the criteria "D", "N", "L", "S" and "H" can only be true if
 the endpoint is in-service, so that requesting "I" at the same time
 (although allowed) would be unnecessary (i.e., redundant).
 Example: If the request for EndpointStateList for one or more
 endpoints includes the parameter line:
    BA/F: BA/S(D,N)
 indicating a request for a report on whether endpoints are
 disconnected or in the notification state.  If a given endpoint is in
 either a "disconnected" or "notification" state, then the report will
 indicate "True" for that endpoint.  If the endpoint is neither in a
 disconnected state nor in a notification state, but is in-service,
 then the report for that endpoint will indicate "False".  If the
 endpoint is out-of-service, then the report for that endpoint will
 indicate "Out of Service".
 In order to only determine whether an endpoint is in-service or out-
 of service, the Call Agent should make a request with only the "I"
 StateType parameter.

2.1.1.3. EndPointNameList and InstantiatedEndpointList Parameters

 EndPointNameList Parameter:
 The EndPointNameList is a list of the endpoint names (i.e., the
 endpoint naming convention for the endpoints configured for service)
 supported by the gateway as qualified by the wildcarded EndPointId,
 and possibly StartEndPointName and MaxNumEndpoints parameters.  This
 list can include one or more lines in the following ABNF format:
    "BA/Z:" 0*WSP RangedLocalName 0*("," 0*WSP RangedLocalName)
 where RangedLocalName is a LocalEndpointName that may include the
 ranged wildcard notation described in Appendix E (section E.5) of
 [3], i.e.,:
    RangeWildcard = "[" NumericalRange *( "," NumericalRange ) "]"
    NumericalRange     = 1*(DIGIT) [ "-" 1*(DIGIT) ].
 Example:
    ba/z: ds/ds1-1/[1-24], ds/ds1-2/[1-24], ds/ds1-3/[1-24]
 or simply:
    ba/z: ds/ds1-[1-3]/[1-24]

Foster, et al. Informational [Page 6] RFC 3624 MGCP Bulk Audit Package November 2003

 Note that, since range wildcards use the character "[" to indicate
 the start of a range, the "[" character MUST NOT be used in endpoint
 names that use range wildcards.
 Note that the ranged wildcard notation (RangeWildcard above) also
 allows commas between ranges like:
    ba/z: ds/ds1-1/[1,3-5,8-24]
 For virtual endpoints, that are automatically created and deleted on
 the fly by the gateway, there is a difference between reporting the
 endpoint names (i.e., the "naming convention") used in describing the
 endpoints and reporting the actual endpoints that are instantiated at
 the time the request is made.  For this case:
  • EndPointNameList is a request to return the naming convention and
  • InstantiatedEndpointList is a request to return the "real" (or

instantiated) endpoints.

 InstantiatedEndpointList Parameter:
    The syntax of the InstantiatedEndpointList value is the same as
    the EndPointNameList value returned with EndPointNameList, i.e., a
    number of lines may be returned with the following syntax:
       "BA/X:" 0*WSP RangedLocalName 0*("," 0*WSP RangedLocalName)
 In the case of hard-wired/physical endpoints (such as DSO's) or other
 persistent endpoints, the InstantiatedEndpointList would normally not
 be requested.  However, if it is requested, the
 InstantiatedEndpointList and the EndPointNameList will be the same.
 For virtual endpoints that are not persistent, an "all of" wild card
 ("*") is returned for the leftmost term of the name, which is
 dynamically assigned in the EndPointNameList to indicate that
 arbitrary names apply, and that the endpoints are virtual and non-
 persistent.  The "all of" wild card notation MUST NOT be used when
 returning the EndPointNameList for persistent endpoints however.  The
 following example illustrates this:
 ba/z: announcement/*
 ba/z: foo/bar/*
 ba/z: foo/foo/*

Foster, et al. Informational [Page 7] RFC 3624 MGCP Bulk Audit Package November 2003

 The "all of" wildcard tells us, that "announcement" is simply the
 leftmost term for a dynamic set of non-persistent virtual endpoints.
 To instantiate one of these endpoints, we would include the "any of"
 wildcard (e.g., "announcement/$") as the LocalEndpointName in the
 EndpointId of a request (e.g., NotificationRequest or
 CreateConnection).  The response would then include the
 SpecificEndpointId indicating the instantiated endpoint.  Also, note
 in the above example that "foo" defines two different levels of non-
 persistent virtual endpoints.

2.1.1.4. ConnectionCountList

 The ConnectionCountList indicates the number of connections on a
 series of endpoints.  It consists of a number of lines with the
 following ABNF syntax:
    "BA/C:" 0*WSP NumConnections 0*(NumConnections)
 where NumConnections is either:
  • a hexadecimal digit indicating the number of connections on the

endpoint corresponding to the position on the list, or

  • the letter "Z" indicating that there are more than 15 connections

on this endpoint.

2.1.1.5. ConnectionModeList

 The ConnectionModeList indicates the connection modes for all the
 connections on a series of endpoints.  It consists of a number of
 lines with the following ABNF syntax:
    "BA/M:" 0*WSP ModeOrCount 0*(ModOrCount)
    ModeOrCount = ConnCount / ConnMode
    ConnMode = "I" / "S" / "R" / "B" / "C" / "L" / "T" / "N" / "U"
 where ConnCount is either hexadecimal value corresponding to 0-15
 connections on an endpoint or the value "Z", indicating that more
 than 15 connections are present.

Foster, et al. Informational [Page 8] RFC 3624 MGCP Bulk Audit Package November 2003

 ConnMode indicates the connection mode where:
  • "I" indicates "inactive" connection mode
  • "S" indicates "sendonly" connection mode
  • "R" indicates "recvonly" connection mode
  • "B" indicates "sendrecv" connection mode
  • "C" indicates "confrnce" connection mode
  • "L" indicates "loopback" connection mode
  • "T" indicates "conttest" connection mode
  • "N" indicates "netwloop" connection mode
  • "U" indicates some other connection mode
 For a definition of MGCP connection modes, refer to section 3.2.2.6
 of [3].
 If an endpoint has no connections on it, ModeOrCount is given the
 value "0".  If there is one connection associated with the endpoint,
 the symbol for the connection mode (ConnMode) is provided.  If, on
 the other hand, there are from 2 to 15 connections, a symbol
 representing the number of connections (ConnCount) is provided
 followed by a list of symbols indicating the connection mode
 (ConnMode) for each connection.  If there are more than 15
 connections, "Z" is indicated for ConnCount and no connection modes
 are provided for the connections on that endpoint.

2.1.1.6. EndpointStateList Parameter

 The EndpointStateList gives an overview of the endpoint state for a
 series of endpoints.  It consists of a number of lines with the
 following ABNF syntax:
    "BA/S:" 0*WSP EndPointState 0*(EndPointState)
    EndPointState = "T" / "F" / "O"
 where:
  • "T" indicates "True"
  • "F" indicates "False"
  • "O" indicates "Out of Service"
 The "True" or "False" determination is based on the criteria supplied
 in StateType parameters when the request is made.
 Note that the EndPointState indicator does not say anything about the
 connection state of the endpoint.

Foster, et al. Informational [Page 9] RFC 3624 MGCP Bulk Audit Package November 2003

2.1.1.7. NextEndpointName Parameter

 The NextEndpointName parameter will be included in the return, if
 there are additional endpoints in this gateway covered by the wild-
 carded endpoint name that were not reported, but for which
 information was available to be reported.
 Note that the NextEndpointName is the LocalEndpointName (as opposed
 to EndpointName) of the next endpoint after the last endpoint
 reported.  The syntax is as follows:
    "BA/NE" ":" 0*WSP LocalEndpointName
 A gateway may supply a report that is shorter than the request if the
 resulting report would have resulted in a message that would be too
 large (i.e., such that the report is larger than the maximum datagram
 size).  In the case where the gateway supplied a response for less
 endpoints than requested, the gateway MUST supply NextEndpointName in
 the response.
 In order to continue the audit on a following set of endpoints, the
 Call Agent can make a further request by using the NextEndpointName
 as the starting point (e.g., as the StartEndpointName in a following
 request).

2.1.1.8. ReportedEndpointList Parameter

 A ReportedEndpointList MUST be provided in a response line before
 list(s) of EndpointStateList and/or ConnectionCountList in order to
 clearly specify the list of endpoints that are being reported.  The
 ABNF syntax is as follows:
    "BA/EL:" 0*WSP LimitedRangedName 0*("," 0*WSP LimitRangedName)
 where LimitedRangedName is a LocalEndpointName that may include a
 ranged wildcard notation (RangeWildcard syntax indicated earlier).
 However, unlike the RangedLocalName that allows the range wildcard
 notation to be used on multiple terms of the local name at the same
 time, LimitedRangedName only allows the range notation to be used for
 the last term, i.e., the following is valid:
    ba/el: ds/ds1-1/[1,3-5,8-24]
 or
    ba/el: ds/ds1-1/[1-24], ds/ds1-2/[1-24], ds/ds1-3/[1-24]

Foster, et al. Informational [Page 10] RFC 3624 MGCP Bulk Audit Package November 2003

 However, the following is not valid:
    ba/el: ds/ds1-[1-3]/[1-24]
 Note that a single bulk audit request may include a request to return
 both ConnectionCountList and EndpointStateList.  However, the
 resulting report that includes both MUST cover the same endpoints.
 A single bulk audit request may also include a request to return both
 EndPointNameList and InstantiatedEndpointList.  However, requests for
 either an EndPointNameList and/or an InstantiatedEndpointList MUST
 NOT include a request for either ConnectionCountList or
 EndpointStateList.

2.1.2. Bulk Auditing of Non-persistent Virtual Endpoints

 Note that gateways that have non-persistent virtual endpoints may
 have instantiated endpoints that are disjoint with respect to the
 name space.  The ReportedEndpointList in front of a
 ConnectionCountList and/or EndpointStateList describes exactly which
 endpoints are being reported.
 Example:
    A Call Agent requests to know about the EndPointNameList for the
    endpoints on a conference bridge:
    AUEP 1200 *@gw1.x.net MGCP 1.0
    BA/F: BA/Z
 Response:
    200 1200 OK
    ba/z: cnf/*
 This indicates the naming convention but in fact not all of these
 endpoints are instantiated.  A request for the list of instantiated
 endpoints, i.e.,:
    AUEP 1201 cnf/*@gw1.x.net MGCP 1.0
    BA/F: BA/X
 might yield:
    200 1201 OK
    ba/x: cnf/[1-3]
    ba/x: cnf/[6-12]

Foster, et al. Informational [Page 11] RFC 3624 MGCP Bulk Audit Package November 2003

 indicating that only these particular endpoints are instantiated.
 Suppose the Call Agent now asks for the ConnectionCountList i.e.,:
    AUEP 1202 cnf/*@gw1.x.net MGCP 1.0
    BA/F: BA/C
 The resulting instantiated virtual endpoints may be disjoint, which
 would be indicated by the ReportedEndpointList in front of the
 ConnectionCountList, e.g.,:
    200 1202 OK
    ba/el: cnf/[1-3]
    ba/c: 035
    ba/el: cnf/[6-12]
    ba/c: 3450333
 or alternatively:
    200 1202 OK
    ba/el: cnf/[1-3], ba/el: cnf/[6-12]
    ba/c: 035
    ba/c: 3450333
 or
    200 1202 OK
    ba/el: cnf/[1-3], ba/el: cnf/[6-12]
    ba/c: 0353450333

2.1.3. Package Specific Return Codes

 The following return codes are specific to this package:
    800     Invalid NextEndpointName
    801     Invalid StartEndpointName
    802     Invalid or unsupported BulkRequestInfo Parameter
    803     Invalid or unsupported StateType
    804     Bulk Audit Type not supported
    805     Incorrectly specified endpoint range
    806     Requested StartEndpoint unknown or unavailable

Foster, et al. Informational [Page 12] RFC 3624 MGCP Bulk Audit Package November 2003

 Note that package specific error codes includes the package name
 following the error code.  For example, if error code 801 occurs in
 response to a request with a transaction ID of 1001 it would be sent
 as:
    801 1001 /BA

2.2. Examples of Package Use

2.2.1. Endpoint List

 This section contains examples of how to obtain a list of endpoints.
 Example 1: This is an example of a gateway that contains a single OC3
 that contains a single level of hierarchy at the T1 level.
 The request is made:
    AUEP 1200 *@gw1.x.net MGCP 1.0
    BA/F: BA/Z
 This may result in a single "BA/Z" term with ranges specifying all of
 the endpoints.
    200 1200 OK
    ba/z: ds/ds1-[1-84]/[1-24]
 Example 2: In this example the gateway has 10 analog lines and a
 single T1.  The same request is made as in example 1, but now the
 response is:
    200 1200 OK
    ba/z: aaln/[1-10]
    ba/z: ds/ds1-1/[1-24]

2.2.2. Connection Count List

 Example1: Audit the number of connections on endpoints of a single
 E1:
    AUEP 2111 ds/e1-3/*@gw1.net
    BA/F: BA/C
 Response:
    200 2111 OK
    BA/EL: ds/e1-3/[1-30]
    BA/C:  012111210001000001000001000010

Foster, et al. Informational [Page 13] RFC 3624 MGCP Bulk Audit Package November 2003

 Example 2: Audit the number of connections on endpoints of a DS3:
    AUEP 1144 ds/ds3-1/*@gateway.net
    BA/F: BA/C
 Response:
    200 1144 OK
    BA/EL: ds/ds3-1/[1-192]
    BA/C:  010000010001000001000001
    BA/C:  001000000101000000001001
    :
    BA/C:  011000100010000010000010
    BA/C:  011111010001000001000001
    BA/C:  011000001100000001000001
    BA/NE: ds/ds3-1/193
 In this case, the response provided by the gateway contained
 information about the first 192 endpoints.  If the ds-3 contained a
 T1 hierarchy, the "BA/EL" and "BA/NE" values would indicate that
 hierarchy e.g.,:
    200 1144 OK
    BA/EL: ds/ds3-1/ds1-1/[1-24]
    BA/C:  010000010001000001000001
    BA/EL: ds/ds3-1/ds1-2/[1-24]
    BA/C:  001000000101000000001001
    :
    BA/EL: ds/ds3-1/ds1-6/[1-24]
    BA/C:  011000100010000010000010
    BA/EL: ds/ds3-1/ds1-7/[1-24]
    BA/C:  011111010001000001000001
    BA/EL: ds/ds3-1/ds1-8/[1-24]
    BA/C:  011000001100000001000001
    BA/NE: ds/ds3-1/ds1-9/1
 The Call Agent could continue to request endpoints by indicating the
 starting endpoint where it left off, i.e., simply using the returned
 "BE/NE" value as the "BA/SE" value for the next request:
    AUEP 1145 ds/ds3-3/*@gw1.net
    BA/F: BA/C
    BA/SE: ds/ds3-1/ds1-9/1

Foster, et al. Informational [Page 14] RFC 3624 MGCP Bulk Audit Package November 2003

 Example 3: In this case, the Call Agent wants to know about the
 connection state of 12 DS0's starting with the endpoint with the
 LocalEndpointName "ds/ds3-1/ds1-6/4":
    AUEP 1146 ds/ds3-1/*@gw1.net
    BA/F: BA/C
    BA/SE: ds/ds3-1/ds1-6/4
    BA/NU: 12
 Response:
    200 1144 OK
    BA/EL: ds/ds3-1/ds1-6/[4-15]
    BA/C:  011000010001
    BA/NE: ds/ds3-1/ds1-6/16

2.2.3. Connection Mode List

 Example: Audit the connection modes for connections on the endpoints
 of a single E1:
    AUEP 2111 ds/e1-3/*@gw1.net
    BA/F: BA/M
 Response:
    200 2111 OK
    BA/EL: ds/e1-3/[1-30]
    BA/M:  0R2BRBBB2RRB000B00000B00000B0000B0
 This shows that:
  • Endpoint ds/e1-3/1 has no connections
  • Endpoint ds/e1-3/2 has one connection and it is in "recvonly"

mode.

  • Endpoint ds/e1-3/3 has two connections which are in "sendrecv" and

"recvonly" mode

  • Endpoints ds/e1-3/4 to ds/e1-3/6 each have one connection - in

"sendrecv" mode in all cases

  • Endpoints ds/e1-3/7 has two connections, both in "recvonly" mode
  • etc.

2.2.4. Endpoint State

 Endpoint state requests and responses are similar.  An example of
 requesting endpoint state similar to example 3 in the previous
 section:

Foster, et al. Informational [Page 15] RFC 3624 MGCP Bulk Audit Package November 2003

    AUEP 1150 ds/ds3-1/*@gw1.net
    BA/F: BA/S(I)
    BA/SE: ds/ds3-1/ds1-6/4
    BA/NU: 12
 Response:
    200 1150 OK
    BA/EL: ds/ds3-1/ds1-6/[4-15]
    BA/S:  TOOTTOOTTOOT
    BA/NE: ds/ds3-1/ds1-6/16
 The request for in-service endpoints returns "True" for all endpoints
 in-service, and "O" for all endpoints "Out of Service".
 A similar request but with additional parameters might be:
    AUEP 1151 ds/ds3-1/*@gw1.net
    BA/F: BA/S(H,N)
    BA/SE: ds/ds3-1/ds1-6/4
    BA/NU: 12
 Response:
    200 1151 OK
    BA/EL: ds/ds3-1/ds1-6/[4-15]
    BA/S:  FFFTFFFFFFFO
    BA/NE: ds/ds3-1/ds1-6/16
 This indicates that at least one of the StateType parameters "H"
 (off-hook) and "N" (notification state) evaluated to true for the
 endpoints that have a "T" associated with then (i.e., ds/ds3-1/ds1-
 6/7 and ds/ds3-1/ds1-6/16 since the request started from ds/ds3-
 1/ds1-6/4).  All other endpoints are neither off-hook nor in the
 "notification state".  Note that endpoint ds/ds3-1/ds1-6/15 is marked
 as being out-of-service.
 It is possible to request both connection state and endpoint state in
 the same request such as:
    AUEP 1151 ds/ds3-1/*@gw1.net
    BA/F: BA/S(H,N), BA/C
    BA/SE: ds/ds3-1/ds1-6/4
    BA/NU: 12

Foster, et al. Informational [Page 16] RFC 3624 MGCP Bulk Audit Package November 2003

 In this case, the response might be:
    200 1151 OK
    BA/EL: ds/ds3-1/ds1-6/[4-15]
    BA/S:  FFFTFFFFFFFO
    BA/C:  011000010001
    BA/NE: ds/ds3-1/ds1-6/16

3. IANA Considerations

 The MGCP package title, "Bulk Audit", with the name, "BA", has been
 registered with IANA as indicated in Appendix C.1 in [3].

4. Security Considerations

 Section 5 of the base MGCP specification [3] discusses security
 requirements for the base protocol, which apply equally to the
 package defined in this document.  Use of a security Protocol such as
 IPsec [4, 5] that provides per message authentication and integrity
 services is required in order to ensure that requests and responses
 are obtained from authenticated sources and that messages have not
 been modified.  Without such services, gateways and Call Agents are
 open to attacks.
 For example, although audit requests from unauthorized sources will
 not modify media gateway state, the information provided could be
 used to locate idle endpoints, which could then lead to making
 unauthorized calls.  Similarly, an attack that modifies a response to
 an audit returned to a Call Agent could lead to a denial of service
 attack in which a Call Agent that is provided misinformation as to
 endpoint state could take some incorrect action such as taking valid
 calls out of service.

Foster, et al. Informational [Page 17] RFC 3624 MGCP Bulk Audit Package November 2003

5. References

 [1]  Crocker, D. and P. Overell, "Augmented BNF for Syntax
      Specifications: ABNF", RFC 2234, November 1997.
 [2]  Bradner, S., "Key words for use in RFCs to Indicate Requirement
      Levels", BCP 14, RFC 2119, March 1997.
 [3]  Andreasen, F. and B. Foster, "Media Gateway Control Protocol
      (MGCP) Version 1.0", RFC 3435, January 2003.
 [4]  Kent, S. and R. Atkinson, "Security Architecture for the
      Internet Protocol", RFC 2401, November 1998.
 [5]  Kent, S. and R. Atkinson, "IP Encapsulating Security Payload
      (ESP)", RFC 2406, November 1998.

6. Authors' Addresses

 Flemming Andreasen
 Cisco Systems
 499 Thornall Street, 8th Floor
 Edison, NJ 08837
 EMail: fandreas@cisco.com
 David Auerbach
 Cisco Systems Inc.
 170 W. Tasman Drive
 San Jose, CA,  95134
 EMail: dea@cisco.com
 Bill Foster
 Cisco Systems
 EMail: bfoster@cisco.com

Foster, et al. Informational [Page 18] RFC 3624 MGCP Bulk Audit Package November 2003

7. Full Copyright Statement

 Copyright (C) The Internet Society (2003).  All Rights Reserved.
 This document and translations of it may be copied and furnished to
 others, and derivative works that comment on or otherwise explain it
 or assist in its implementation may be prepared, copied, published
 and distributed, in whole or in part, without restriction of any
 kind, provided that the above copyright notice and this paragraph are
 included on all such copies and derivative works.  However, this
 document itself may not be modified in any way, such as by removing
 the copyright notice or references to the Internet Society or other
 Internet organizations, except as needed for the purpose of
 developing Internet standards in which case the procedures for
 copyrights defined in the Internet Standards process must be
 followed, or as required to translate it into languages other than
 English.
 The limited permissions granted above are perpetual and will not be
 revoked by the Internet Society or its successors or assignees.
 This document and the information contained herein is provided on an
 "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
 TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
 BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
 HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
 MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.

Acknowledgement

 Funding for the RFC Editor function is currently provided by the
 Internet Society.

Foster, et al. Informational [Page 19]

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