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Cisco IOS Software Releases 12.2 T

GKTMP Messages (GK API Guide Version 4.2)

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GKTMP Messages

Table Of Contents

GKTMP Messages

GKTMP RAS Messages

Message Line

Message Header

Message Body

Registration Messages

Request RRQ

Response RRQ

Response RCF

Response RRJ

Unregistration Message

Request URQ

Command URQ

Result URQ

Admission Messages

Request ARQ

Response ARQ

Response ACF

Response ARJ

Location Messages

Request LRQ

Response LRQ

Request LCF

Response LCF

Request LRJ

Response LRJ

Disengage Messages

Request DRQ

Resource Messages

Request RAI

Bandwidth Messages

Request BRQ

Response BRQ

Response BCF

Response BRJ

Progress Messages

Response RIP

Request IRR

Request ALV

Response ALV

Trigger Registration Messages

Message Line

Message Header

Message Body

Register RRQ and RAI

Register URQ

Register ARQ, DRQ, IRR, and BRQ

Register LRQ

Register LCF

Register LRJ

Additional Messages

GTD

AlternateGK

FromReplyAddress

ServiceControlSession

CallCapacity

CarrierInfo

TrunkGroupInfo

Alias-Address

PerCallInfo

RemoteZone

Transport-Address

ClearToken

CryptoToken


GKTMP Messages


This chapter describes GKTMP messages and contains the following sections:

GKTMP RAS Messages

Trigger Registration Messages

The GKTMP messages are used for communication between the Cisco IOS Gatekeeper and the external application. There are two types of GKTMP messages:

GKTMP RAS Messages—Used to exchange the contents RAS messages between the Cisco IOS Gatekeeper and the external application.

Trigger Registration Messages—Used by the external application to indicate to the Cisco IOS Gatekeeper which RAS message should be forwarded.

GKTMP RAS Messages

The general format of all GKTMP RAS messages is as follows:

Single message line

One or more message header lines

Blank line, which separates the message header from the message body

Zero or more message body lines

Message Line

Each GKTMP RAS message is either a request or a response. Requests are generated by the Cisco IOS Gatekeeper and responses are generated by the external application.

The first line of each GKTMP RAS message sent by the Cisco IOS Gatekeeper uses the format:

REQUEST RAS_message_type

The first line of each GKTMP RAS message sent by the external application uses the format:

RESPONSE RAS_message_type

Possible RAS message types are as follows:

RRQ—Registration request

RCF—Registration confirm

RRJ—Registration reject

URQ—Unregistration request

ARQ—Admission request

ACF—Admission confirm

ARJ—Admission reject

LRQ—Location request

LCF—Location confirm

LRJ—Location reject

RIP—Request in progress

DRQ—Disengage request

RAI—Resource availability information

BRQ—Bandwidth request

BCF—Bandwidth confirm

BRJ—Bandwidth reject

IRR—Information request


Note The Cisco IOS Gatekeeper does not generate GKTMP Request RRQ messages for lightweight RRQ messages, which are used by H.323 endpoints as a keep-alive mechanism to refresh existing registrations.


Message Header

The message line is immediately followed by the message header. Each message header contains a field name and a value, separated by a colon (field:value). Table 4-1 shows the possible fields:

Table 4-1 Message Header Fields

Field Names
Field Values

Version-Id

Version of the protocol that the sender is running. The version ID consists of a major number (gk_major) and a minor number (gk_minor). For example,
version 1 is represented as 100.

From

String that identifies the originator of the message. For requests from the Cisco IOS Gatekeeper, this field contains the gatekeeper ID. For responses from the external application, this field contains the server ID.

To

String that identifies the receiver of the message. For requests from the Cisco IOS Gatekeeper, this field contains the server ID. For responses from the external application, this field contains the ID of the gatekeeper that initiated the request.

Content-Length

Number of octets contained in the message body. If the message body is null, this field can be omitted.

Transaction-Id

String that identifies the transaction. If this field is present in the request from the Cisco IOS Gatekeeper, it must be echoed in the response from the external application.

Notification-Only

None. No value is included after the colon. If this field name is present, it indicates to the external application no response should be sent. Request URQ must contain this field. Also, Request RRQ contains this field when that message is used to populate the external application's registration database.


The message header is followed immediately by a blank line.

Message Body

The message body follows the blank line. Each line in the message body contains a tag and a value, separated by an equal sign (tag=value). The tags are case-sensitive and denote an RAS message field. The possible tags depend on the GKTMP RAS message.


Note If the message body is null, the message must terminate with a CRFL after the message header.


In some cases, depending on the field type, the value is preceded a value-type identifier followed by a colon (tag=type:value).

Possible field types are as follows:

Alias-Address—This type of field can contain a series of addresses separated by spaces. Each is preceded by a value-type identifier that indicates the type of address. H indicates that the address is an H.323 ID; E indicates that the address is an E.164 address; M indicates that the address is an e-mail ID.

Transport-Address—This type of field contains an address. Currently, only one value-type identifier is possible for this field type. That is I, which indicates that the address is an IP version 4 address. The address is specified in dotted-decimal notation and can be followed by a colon and a port number.

Endpoint-Type—This type of field indicates the type of endpoint. Possible values are: gatekeeper, terminal, mcu, proxy, voice-gateway, h320-gateway, and other-gateway.

Supported-Prefix—This type of field indicates a supported technology prefix. Possible values are the digits 0 through 9 and the pound sign (#).

Globally-Unique-Identifier (GUID)—This type of field contains the 16-octet conference ID or call ID that uniquely identifies the call or conference. The IDs are specified in hexadecimal format.

Bandwidth—This type of field contains an unsigned integer from 0 through 4294967295 that indicates the bandwidth in 100 bits per second.

Boolean—This type of field contains a single character. T or t for true; F or f for false.

IA5 String—This type of field contains characters from the International Alphabet 5 (IA5), which is a character set defined by the ITU X.400 Message Handling System specification.

cryptoToken—This type of field contains one of the cryptoToken types defined for the CryptoH323Token field specified in H.225. Currently, the only type of cryptoToken supported is the cryptoEPPwdHash.

HASHED-EncodedPwdCertToken—This type of field contains a 16 octet IA5String. It represents the RAS Message Digest 5 (MD5) hashed encoded PwdCertToken.

TimeStamp—This type of field contains a 32-bit integer that represents Universal Time Coordinated (UTC) time.

OBJECT-IDENTIFIER—This type of field contains a sequence of non-negative integer values separated by dots, which is used to uniquely identify an object.

UseSpecifiedTransport—This type of field contains a string that indicates the transport layer that is used for the signaling: Annex E/UDP or TCP.

AlternateGK—This type of field contains a set of fields enclosed in braces ({ }). Each field is identified by a tag and separated from the other fields by SP (ASCII space, 0x20) characters. This field can contain more than one set of fields, each enclosed by braces.

AlternateEndpoint—This type of field contains a set of fields enclosed in braces. Each field is identified by a tag and separated from the other fields by SP (ASCII space, 0x20) characters. A message body line containing an AlternateEndpoint field must pertain to a single endpoint. Multiple call signal addresses and tokens that pertain to the same endpoint can be provided in a single message body line. If there are multiple AlternateEndpoints, each pertaining to a different H.323 endpoint, the information about the alternate endpoints must be provided in separate message body lines.

AlternateTransportAddress—This type of field contains a single sub-field enclosed in braces. The fields within the braces pertain to a single instance of a RAS AlternateTransportAddress structure. They are defined as a Transport-Address and are encoded as defined for the Transport-Address field.

clearToken—This type of field contains a set of fields enclosed in braces. Each field is identified by a tag and separated from the other fields by SP (ASCII space, 0x20) characters. The fields within the braces pertain to a single instance of a RAS ClearToken structure. However, the message line of a clearToken field can contain multiple instances, each enclosed in braces and separated by a space character. The clearToken field can be embedded within an AlternateEndpoint field.

remoteZone—This type of field contains a set of fields enclosed in braces. Each field is identified by a tag and separated from the other fields by SP (ASCII space, 0x20) characters. The fields within the braces pertain to a single instance of a remoteZone structure. However, the message line of a remoteZone field can contain multiple instances, each enclosed in braces and separated by a space character.

This section describes the possible fields for each message. When the external application sends a response, it includes only the fields that it has altered. Unaltered fields must not be included.

Registration Messages

Registration messages are used to control which H.323 endpoints are in the gatekeeper's zone.

This section describes the following:

Request RRQ

Response RRQ

Response RCF

Response RRJ

Request RRQ

This message is sent from the Cisco IOS Gatekeeper to the external application when an H.323 endpoint wants to join the zone. This message can be used to populate the external application's registration database. In this case, the request is sent as a notification only and no response is expected from the external application.

Table 4-2 shows the possible Request RRQ tags:

Table 4-2 Request RRQ Tags

Tag
Field Type
Mandatory or Optional
Corresponding RAS Message Field

c

Transport-Address

Mandatory

RRQ:callSignalAddress. See Transport-Address.

r

Transport-Address

Mandatory

RRQ:rasAddress. See Transport-Address.

a

Alias-Address

Optional

RRQ:terminalAlias

t

Endpoint-Type

Mandatory

RRQ:terminalType

p

Supported-Prefix

Optional

RRQ:terminalType:gateway:protocol:*:supportedPrefixes

$

cryptoToken

Optional

RRQ:cryptoTokens. See CryptoToken.

T

clearToken

Optional

RRQ:tokens. See ClearToken.

C

Boolean

Optional

RRQ:callCapacityReportingCapability

K

CallCapacity

Optional

RRQ:capacity. See CallCapacity.


Response RRQ

This message is sent from the external application to the Cisco IOS Gatekeeper in response to a Request RRQ message. If the external application has no interest in the Request RRQ message, it returns a Response RRQ with a null body. Otherwise, the external application modifies the fields as appropriate and sends the response with the updated information to the Cisco IOS Gatekeeper for further processing.

For Response RRQ, the possible tags are shown in Table 4-3:

Table 4-3 Response RRQ Tags

Tag
Field Type
Mandatory or Optional
Corresponding RAS Message Field

a

Alias-Address

Optional

RRQ:terminalAlias

p

Supported-Prefix

Optional

RRQ:terminalType:gateway:protocol: *:supportedPrefixes

F

Boolean

Optional

Do not propagate this message onward.


Response RCF

This message is sent from the external application to the Cisco IOS Gatekeeper in response to a Request RRQ. This message indicates that the external application has completed the processing of the request.

For Response RCF, the possible tags are shown in Table 4-4:

Table 4-4 Response RCF Tags

Tag
Field Type
Mandatory or Optional
Corresponding RAS Message Field

a

Alias-Address

Optional

RRQ:terminalAlias

p

Supported-Prefix

Optional

RRQ:terminalType:gateway:protocol:
*:supportedPrefixes

G

AlternateGK

Optional

RCF:alternateGatekeeper. See AlternateGK.


Response RRJ

This message is sent from the external application to the Cisco IOS Gatekeeper in response to a Request RRQ. It indicates that the Cisco IOS Gatekeeper should reject the request for the specified reason.

For Response RRJ, the possible tag is shown in Table 4-5:

Table 4-5 Response RRJ Tag

Tag
Field Type
Mandatory or Optional
Corresponding RAS Message Field

R

RRJ-Reason

Mandatory

RRJ:rejectReason


Possible values for the rejectReason are:

undefinedReason

securityDenial

resourceUnavailable

discoveryRequired

invalidRevision

invalidCallSignalAddress

invalidRASAddress

duplicateAlias

invalidTerminalType

transportNotSupported

transportQOSNotSupported

invalidAlias

fullRegistrationRequired

additiveRegistrationNotSupported

invalidTerminalAlias

genericDataReason

Unregistration Message

Unregistration messages are used to remove an H.323 endpoint from a gatekeeper zone.

This section describes the following:

Request URQ

Command URQ

Result URQ

Request URQ

This message is sent from the Cisco IOS Gatekeeper to the external application when the H.323 endpoint wants to leave the zone or when its registration expires. This request is sent as a notification only. No response is generated by the external application.

For Request URQ, the possible tag is shown in Table 4-6:

Table 4-6 Request URQ

Tag
Field Type
Mandatory or Optional
Corresponding RAS Message Field

c

Transport-Address

Mandatory

URQ:callSignalAddress. See Transport-Address.


Command URQ

The Command URQ message is sent from the application server to the gatekeeper at any time to unregister an endpoint. The gatekeeper sends a URQ message to the endpoint and removes it from its registration database. The endpoint is identified by its call signaling address (IP address and port). The server can also specify an optional reason and alternate gatekeeper information.

Table 4-7 shows the new Command URQ tags:

Table 4-7 New Command URQ Tags

Tag
Field Type
Mandatory or Optional
Corresponding RAS Message Field

c

Transport-Address

Mandatory

URQ:callSignalAddress. See Transport-Address.

R

URQ-Reason

Optional

URQ:reason

G

AlternateGK

Optional

URQ:alternateGatekeeper. See AlternateGK.


Possible values for the reason are:

reregistrationRequired

ttlExpired

securityDenial

undefinedReason

Result URQ

The Result URQ message is sent from the gatekeeper to the application server to report the result of a Command URQ transaction as long as the command did not specify Notification-Only: in the message header. The endpoint is identified by its call signaling address (IP address and port).

If the endpoint was found and unregistered, the message header indicates Status: success. Otherwise it indicates Status: invalidGKID or Status: invalidEndpoint.


Note Success just means that a URQ message was sent to the endpoint and that it was removed from the gatekeeper registration database without error. It does not mean that a UCF message was received from the endpoint. The gatekeeper does not wait to receive a UCF message before sending the Result URQ message to the server.


Table 4-8 shows the new Result URQ tags:

Table 4-8 New Result URQ Tags

Tag
Field Type
Mandatory or Optional
Corresponding RAS Message Field

c

Transport-Address

Mandatory

URQ:callSignalAddress. See Transport-Address.


Admission Messages

Admission messages are used to control which H.323 endpoints can participate in calls.

This section describes the following:

Request ARQ

Response ARQ

Response ACF

Response ARJ

Request ARQ

This message is sent from the Cisco IOS Gatekeeper to the external application when an H.323 endpoint wants to initiate a call.

For Request ARQ, the possible tags are shown in Table 4-9:

Table 4-9 Request ARQ 

Tag
Field Type
Mandatory or Optional
Corresponding RAS Message Field

s

Alias-Address

Mandatory

ARQ:srcInfo

S

Transport-Address

Optional

ARQ:srcCallSignalAddress. See Transport-Address.

d

Alias-Address

Optional

ARQ:destinationInfo

D

Transport-Address

Optional

ARQ:destCallSignalAddress. See Transport-Address.

x

Alias-Address

Optional

ARQ:destExtraCallInfo

b

Bandwidth

Mandatory

ARQ:bandWidth

A

Boolean

Mandatory

ARQ:answerCall

c

GUID

Optional

ARQ:callIdentifier

C

GUID

Mandatory

ARQ:conferenceID

m

Boolean

Optional

ARQ:canMapAlias

e

IA5String

Optional

ARQ:nonStandardData:redirectNumber

E

integer

Optional

ARQ:nonStandardData:redirectReason1

p

integer

Optional

ARQ:nonStandardData:callingPartyNumOctet3a2

w

IA5string

Optional

ARQ:nonStandardData:displayIE

i

TransportAddress

Mandatory

arqing-endpoint identifier3

$

cryptoToken

Optional

ARQ:cryptoTokens. See CryptoToken.

T

clearToken

Optional

ARQ:tokens. See ClearToken.

B

IA5string

Optional

ARQ:nonStandardData:interfaceSpecific:BillingInfo

g

GTD

Optional

ARQ:nonStandardData:gtd. See GTD.

I

IA5String

Optional

ARQ:nonStandardData:interfaceDescriptor

J

IA5String

Optional

ARQ:circuitInfo:destinationCircuitID:group

K

callCapacity

Optional

ARQ:capacity. See CallCapacity.

L

IA5String

Optional

ARQ:circuitInfo:sourceCircuitID:group

P

IA5String

Optional

ARQ:circuitInfo:sourceCircuitID:group

Q

IA5String

Optional

ARQ:circuitInfo:destinationCircuitID:group

U

IA5String

Optional

ARQ:tokens:cisco_IZCT_OID:IZCToken:izctSrcZone

W

IA5String

Optional

ARQ:tokens:cisco_IZCT_OID:IZCToken:izctDstZone

V

Integer

Optional

ARQ:nonStandardInfo:reRouteCount

v

IA5 String

Optional

ARQ:nonStandardInfo:terminationCause:
releaseCompleteCauseIE


Possible values for the redirectReason are:

0—Unknown

1—Call forwarding busy or called DTE busy

2—Call forwarded, no reply

4—Call deflection

9—Called DTE out of order

10—Call forwarding by the called DTE

15—Call forwarding unconditional or systematic call redirection

CallingPartyNumOctet3a is from the Q.931 Setup octet 3a of calling party number.

When an H.323 endpoint sends an ARQ to the Cisco IOS Gatekeeper, it includes its endpointIdentifier. Because this value is local and has meaning to the Cisco IOS Gatekeeper only and not to the external application, the Cisco IOS Gatekeeper substitutes a more meaningful value of CallSignalAddress in its Request ARQ messages.

Response ARQ

This message is sent from the external application to the Cisco IOS Gatekeeper in response to a Request ARQ message. If the external application has no interest in the Request ARQ message, it returns a Response ARQ with a null body. Otherwise, it modifies the fields as appropriate and sends the response with the updated information to the Cisco IOS Gatekeeper for further processing.

For Response ARQ, the possible tags are shown in Table 4-10:

Table 4-10 Response ARQ

Tag
Field Type
Mandatory or Optional
Corresponding RAS Message Field

d

Alias-Address

Optional

ARQ:destinationInfo

D

Transport-Address

Optional

ARQ:destCallSignalAddress. See Transport-Address.

x

Alias-Address

Optional

ARQ:destExtraCallInfo

b

Bandwidth

Optional

ARQ:bandWidth

e

IA5String

Optional

ARQ:nonStandardData:redirectNumber

E

integer

Optional

ARQ:nonStandardData:redirectReason

w

IA5string

Optional

ARQ:nonStandardData:displayIE

z

remoteZone

Optional

None. See RemoteZone.

T

clearToken

Optional

ARQ:tokens. See ClearToken.

c

integer

Optional

None1

p

integer

Optional

None2

A

alternateEndpoint

Optional

ARQ:alternateEndpoints

g

GTD

Optional

ARQ:nonStandardData:gtd. See GTD.

I

IA5String

Optional

ARQ:circuitInfo:sourceCircuitID:group

J

carrierInfo

Optional

See CarrierInfo.

F

Boolean

Optional

Do not propagate this message onward.

s

Alias-Address

Optional

ARQ:srcInfo. See Alias-Address.

P

IA5String

Optional

ARQ:circuitInfo:sourceCircuitID:group

Q

trunkGroupInfo

Optional

See TrunkGroupInfo.

y

ServiceControlSession

Optional

ACF:ServiceControlSession. See ServiceControlSession.

1 Reflects the cost value of the primary endpoint, if any, whose address is returned in the `D' field of this message. It should only be sent if the endpoint is filled in.

2 Reflects the priority value of the primary endpoint, if any whose address is returned in the `D' field of this message. It should only be sent if the endpoint is filled in.


The external application has the option of reducing the bandwidth.

If this field is included, the Cisco IOS Gatekeeper sends LRQs to all the listed zones. The zone with the least cost and highest priority that returns and LCF is chosen for inclusion in the ACF that is sent to the endpoint.

If the message contains an alternateEndpoint field, the additional fields shown in Table 4-11 are included:

Table 4-11 Additional Fields

Tag
Field Type
Mandatory or Optional
Description

C

Integer

Optional

Cost value associated with the zone

p

Integer

Optional

Priority value associated with the zone

c

Transport-Address

Mandatory

alternateEndpoints:callSignalAddress. See Transport-Address.

J

IA5string

Optional

CarrierId

Q

IA5string

Optional

TrunkGroupLabel

T

clear-Token

Optional

alternateEndpoints:tokens


Response ACF

This message is sent from the external application to the Cisco IOS Gatekeeper in response to a Request ARQ. The message indicates that the external application has completed the processing of the request.

For Response ACF, the possible tags are shown in Table 4-12:

Table 4-12 Response ACF 

Tag
Field Type
Mandatory or Optional
Corresponding RAS Message Field

d

Alias-Address

Optional

ACF:destinationInfo

D

Transport-Address

Mandatory

ACF:destCallSignalAddress. See Transport-Address.

x

Alias-Address

Optional

ACF:destExtraCallInfo

X

Alias-Address

Optional

ACF:remoteExtensionAddress

b

Bandwidth

Optional

ARQ:bandWidth

t

Endpoint-type

Optional

ACF:destinationType

T

ClearToken

Optional

ACF:tokens. See ClearToken.

A

AlternateEndpoint

Optional

ACF:alternateEndpoints

N

AlternateTransportAddr

Optional

ACF:alternateTransportAddress

u

useSpecifiedTransport

Optional

ACF:useSpecifiedAddress. SeeMessage Body.

g

GTD

Optional

ACF:nonStandardData:gtd:gtdData. See GTD.

s

Service-Descriptor

Optional

ACF:nonStandardData:serviceDescriptor

y

ServiceControlSession

Optional

ACF:ServiceControlSession. See ServiceControlSession.

J

carrierInfo

Optional

See CarrierInfo.

Q

trunkGroupInfo

Optional

See TrunkGroupInfo.


If the message contains an AlternateEndpoint field, the additional fields shown in Table 4-13 are included:

Table 4-13 Additional Fields

Tag
Field Type
Mandatory or Optional
Corresponding RAS Message Field

c

Transport-Address

Mandatory

alternateEndpoints:callSignalAddress. See Transport-Address.

T

clearToken

Optional

alternateEndpoints:tokens. See ClearToken.

C

Integer

Optional

None1

p

Integer

Optional

None1

J

IA5string

Optional

CarrierId

Q

IA5string

Optional

TrunkGroupLabel

1 The `C' and `p' parameters define the associated cost and priority of using this endpoint. The Gatekeeper merges the endpoints in order of their cost/priority and present an ordered list. Remote endpoints, if any (obtained by sending LRQs), are assigned the cost value of the zone and merged accordingly.


If the message contains an AlternateTransportAddr field, the additional field shown in Table 4-14 is included:

Table 4-14 Additional Field

Tag
Field Type
Mandatory or Optional
Corresponding RAS Message Field

I

Transport-Address

Mandatory

IP address and port for Annex E. See Transport-Address.


Response ARJ

This message is sent from the external application to the Cisco IOS Gatekeeper in response to a Request ARQ. The message indicates that the Cisco IOS Gatekeeper should reject the request for the specified reason.

For Response ARJ, the possible tag is shown in Table 4-15:

Table 4-15 Response ARJ

Tag
Field Type
Mandatory or Optional
Corresponding RAS Message Field

R

ARJ-Reason

Mandatory

ARJ:rejectReason

y

ServiceControlSession

Optional

ACF:ServiceControlSession. See ServiceControlSession.

v

IA5String

Optional

ARJ:terminationCause:releaseCompleteCauseIE1

1 This field is included if the GKTMP server wishes to provide a Q.850 cause code that it wants to be used to release the call.


Possible values for rejectReason are:

calledPartyNotRegistered

invalidPermission

requestDenied

undefinedReason

resourceUnavailable

securityDenial

carrierIdUnspecified (maps to undefinedReason)

carrierIdUnknown (maps to undefinedReason)

ingressCarrierInactive (maps to undefinedReason)

carrierOrigPcntExceeded (maps to undefinedReason)

carrierMaxUnitsExceeded (maps to undefinedReason)

destinationUnknown (maps to undefinedReason)

noRouteAvailable (maps to undefinedReason)

callerNotRegistered

routeCallToGatekeeper

invalidEndpointID

qosControlNotSupported

incompleteAddress

aliasesInconsistent

routeCallToSCN

exceedsCallCapacity

collectDestination

collectPin

genericDataReason

neededFeatureNotSupported

Location Messages

Location messages are used by gatekeepers to communicate with each other to process interzone calls.

This section describes the following:

Request LRQ

Response LRQ

Request LCF

Response LCF

Request LRJ

Response LRJ

Request LRQ

This message is sent from the Cisco IOS Gatekeeper to the external application when the Cisco IOS Gatekeeper has received an interzone location request.

For Request LRQ, the possible tags are shown in Table 4-16:

Table 4-16 Request LRQ 

Tag
Field Type
Mandatory or Optional
Corresponding RAS Message Field

s

Alias-Address

Optional

LRQ:srcInfo

d

Alias-Address

Mandatory

LRQ:destinationInfo

e

IA5String

Optional

LRQ:nonStandardData:redirectNumber

E

integer

Optional

LRQ:nonStandardData:redirectReason1

p

integer

Optional

LRQ:nonStandardData:callingPartyNumOctet3a2

w

IA5String

Optional

LRQ:nonStandardData:displayIE

c

IA5String

Optional

LRQ:nonStandardData:callingPartyNum

T

clearToken

Optional

LRQ:tokens. See ClearToken.

g

GTD

Optional

LRQ:nonStandardData:gtd. See GTD.

I

IA5String

Optional

LRQ:nonStandardData:interfaceDescriptor

J

IA5String

Optional

LRQ:circuitInfo:destinationCircuitID:group

L

IA5String

Optional

LRQ:circuitInfo:sourceCarrierID:group

b

Integer

Optional

LRQ:nonStandardData:bandwidth

C

IA5String

Optional

LRQ:nonStandardData:callIdentifier

P

IA5String

Optional

LRQ:circuitInfo:sourceCircuitID:group

Q

IA5String

Optional

LRQ:circuitInfo:destinationCircuitID:group

S

IA5String

Optional

LRQ:tokens:cisco_IZCT_OID:IZCTToken:izctSrctZone

D

IA5String

Optional

LRQ:tokens:cisco_IZCT_OID:IZCTToken:izctDstZone

i

FromReplyAddress

Optional

See FromReplyAddress.

V

Integer

Optional

ARQ:nonStandardInfo:reRouteCount

v

IA5 String

Optional

ARQ:nonStandardInfo:terminationCause:
releaseCompleteCauseIE


Possible values for the redirectReason are:

0—Unknown

1—Call forwarding busy or called DTE busy

2—Call forwarded, no reply

4—Call deflection

9—Called DTE out of order

10—Call forwarding by the called DTE

15—Call forwarding unconditional or systematic call redirection

CallingPartyNumOctet3a is from the Q.931 Setup octet 3a of calling party number.

Response LRQ

This message is sent from the external application to the Cisco IOS Gatekeeper in response to a Request LRQ message. If the external application has no interest in the Request LRQ message, it returns a Response LRQ with a null body. Otherwise, it modifies the fields as appropriate and sends the response with the updated information to the Cisco IOS Gatekeeper for further processing.

For Response LRQ, the possible tags are shown in Table 4-17:

Table 4-17 Response LRQ 

Tag
Field Type
Mandatory or Optional
Corresponding RAS Message Field

d

Alias-Address

Optional

LRQ:destinationInfo

z

remoteZone

Optional

None. See RemoteZone.

T

clearToken

Optional

ARQ:tokens. See ClearToken.

c

integer

Optional

None1

p

integer

Optional

None2

A

alternateEndpoint

Optional

ARQ:alternateEndpoints

g

GTD

Optional

LRQ:nonStandardData:gtd. See GTD.

I

IA5String

Optional

LRQ:circuitInfo:sourceCircuitID:group

J

carrierInfo

Optional

See CarrierInfo.

F

Boolean

Optional

Do not propagate this message onward.

s

Alias-Address

Optional

LRQ:srcInfo. See Alias-Address.

Q

trunkGroupInfo

Optional

See TrunkGroupInfo.

P

IA5String

Optional

LRQ:circuitInfo:sourceCircuitID:group

1 Reflects the cost value of the primary endpoint, if any, whose address is returned in the `D' field of this message. It should only be sent if the endpoint is filled in.

2 Reflects the priority value of the primary endpoint, if any whose address is returned in the `D' field of this message. It should only be sent if the endpoint is filled in.


If the message contains an alternateEndpoint field, the additional fields shown in Table 4-18 are included:

Table 4-18 Additional Fields

Tag
Field Type
Mandatory or Optional
Description

C

Integer

Optional

Cost value associated with the zone

p

Integer

Optional

Priority value associated with the zone

c

Transport-Address

Mandatory

alternateEndpoints:callSignalAddress. See Transport-Address.

J

IA5string

Optional

CarrierId

Q

IA5string

Optional

TrunkGroupLabel

T

clear-Token

Optional

alternateEndpoints:tokens


Request LCF

This message is sent from the Cisco IOS Gatekeeper to the external application when the Cisco IOS Gatekeeper has received an LCF from the remote Cisco IOS Gatekeeper. This gives the external application an opportunity to accept (Response LCF), modify (Response LCF), or reject (Response LRJ) the information contained in the LCF.

For Request LCF, the possible tags are shown in Table 4-19:

Table 4-19 Request LCF

Tag
Field Type
Mandatory or Optional
Corresponding RAS Message Field

s

Alias-Address

Optional

LRQ:srcInfo

e

IA5String

Optional

LRQ:nonStandardData:redirectNumber

E

integer

Optional

LRQ:nonStandardData:redirectReason

p

integer

Optional

LRQ:nonStandardData:callingPartyNumOctet3a

w

IA5String

Optional

LRQ:nonStandardData:displayIE

c

IA5String

Optional

LRQ:nonStandardData:callingPartyNum

d

Alias-Address

Mandatory

LRQ/LCF:destinationInfo

D

Transport-Address

Mandatory

LCF:callSignalAddress. See Transport-Address.

r

Transport-Address

Mandatory

LCF:rasAddress. See Transport-Address.

x

Alias-Address

Optional

LCF:destExtraCallInfo

X

Alias-Address

Optional

LCF:remoteExtensionAddress

t

Endpoint-Type

Optional

LCF:destinationType

N

AlternateTransportAddr

Optional

LCF:AlternateTransportAddress

u

useSpecifiedTransport

Optional

ACF:useSpecifiedAddress

T

clearToken

Optional

LCF:tokens. See ClearToken.

g

GTD

Optional

LCF:nonStandardData:gtd:gtdData. See GTD.

y

ServiceControlSession

Optional

LCF:ServiceControlSession. See ServiceControlSession.

C

IA5String

Optional

ARQ:callIdentifier



The destinationInfo from the LCF is used if one is available. Otherwise, the destinationInfo from the LRQ is used.

If the message contains an AlternateTransportAddr field, the following additional field shown in Table 4-20 is included:

Table 4-20 Additional Field

Tag
Field Type
Mandatory or Optional
Corresponding RAS Message Field

I

Transport-Address

Mandatory

IP address and port for Annex E. See Transport-Address.


Response LCF

This message is sent from the external application to the Cisco IOS Gatekeeper in response to a Request LRQ. The message indicates that the external application has completed the processing of the request.

This message can also be sent to the Cisco IOS Gatekeeper from the external application in response to a Request LCF or a Request LRJ. In the case of a Request LCF, the response can contain:

A null message body, which indicates that the external application accepts the information in the Request LCF.

Modified fields, which indicates that the external application wants to use different values than those included in the Request LCF.

In the case of a Request LRJ, the response contains an alternate destination.

For Response LCF, the possible tags are shown in Table 4-21:

Table 4-21 Response LCF

Tag
Field Type
Mandatory or Optional
Corresponding RAS Message Field

d

Alias-Address

Optional

LCF:destinationInfo

D

Transport-Address

Mandatory

LCF:destCallSignalAddress. See Transport-Address.

r

Transport-Address

Mandatory

LCF:rasAddress. See Transport-Address.

x

Alias-Address

Optional

LCF:destExtraCallInfo

X

Alias-Address

Optional

LCF:remoteExtensionAddress

t

Endpoint-Type

Optional

LCF:destinationType

A

AlternateEndpoint

Optional

ACF:alternateEndpoints

N

AlternateTransportAddr

Optional

LCF:AlternateTransportAddress

u

useSpecifiedTransport

Optional

ACF:useSpecifiedAddress

T

clearToken

Optional

LCF:tokens. See ClearToken.

g

GTD

Optional

LCF:nonStandardData:gtd:gtdData. See GTD.

s

Service-Descriptor

Optional

LCF:nonStandardData:serviceDescriptor

y

ServiceControlSession

Optional

ACF:ServiceControlSession. See ServiceControlSession.

J

carrierInfo

Optional

See CarrierInfo.

Q

trunkGroupInfo

Optional

See TrunkGroupInfo.



Note The D and r are not required if the Response LCF is being sent in reply to a Request LCF.


If the message contains an AlternateTransportAddr field, the additional field shown in Table 4-22 included:

Table 4-22 Additional Field

Tag
Field Type
Mandatory or Optional
Corresponding RAS Message Field

I

Transport-Address

Mandatory

IP address and port for Annex E. See Transport-Address.


Request LRJ

This message is sent from the Cisco IOS Gatekeeper to the external application when the Cisco IOS Gatekeeper has received an LRJ from a remote Cisco IOS Gatekeeper. This gives the Cisco IOS Gatekeeper the opportunity to accept the rejection (Response LRJ) or propose an alternative destination (Response LCF).

For Request LRJ, the possible tags are shown in Table 4-23:

Table 4-23 Request LRJ

Tag
Field Type
Mandatory or Optional
Corresponding RAS Message Field

s

Alias-Address

Optional

LRQ:srcInfo

d

Alias-Address

Mandatory

LRQ:destinationInfo

e

IA5String

Optional

LRQ:nonStandardData:redirectNumber

E

integer

Optional

LRQ:nonStandardData:redirectReason

p

integer

Optional

LRQ:nonStandardData:callingPartyNumOctet3a

w

IA5String

Optional

LRQ:nonStandardData:displayIE

c

IA5String

Optional

LRQ:nonStandardData:callingPartyNum

R

LRJ-reason

Mandatory

LRJ:rejectReason

y

ServiceControl
Session

Optional

 

C

IA5String

Optional

ARQ:callIdentifier

v

IA5String

Optional

LRJ:terminationCause:releaseCompleteCauseIE1

1 This field is included if the GKTMP server wishes to provide a Q.850 cause code that it wants to be used to release the call.


Response LRJ

This message is sent from the external application to the Cisco IOS Gatekeeper in response to a Request LRQ. The message indicates that the Cisco IOS Gatekeeper should reject the request for the specified reason.

This message can also be sent to the Cisco IOS Gatekeeper from the external application in response to a Request LCF or a Request LRJ. In the case of a Request LCF, this response rejects the information provided in the LCF for the specified reason. In the case of a Request LRJ, this response acknowledges the rejection. The reason is optional when the Response LRJ is sent due to a Request LRJ.

For Response LRJ, the possible tag is shown in Table 4-24:

Table 4-24 Response LRJ

Tag
Field Type
Mandatory or Optional
Corresponding RAS Message Field

R

LRJ-Reason

Mandatory (LRQ, LCF)

Optional (LRJ)

LRJ:rejectReason

y

ServiceControlSession

Optional

ACF:ServiceControlSession

v

IA5String

Optional

LRJ:terminationCause:releaseCompleteCauseIE1

1 This field is included if the GKTMP server wishes to provide a Q.850 cause code that it wants to be used to release the call.


Possible values for rejectReason are:

notRegistered

invalidPermission

requestDenied

undefinedReason

securityDenial

carrierIdUnspecified (maps to undefinedReason)

carrierIdUnknown (maps to undefinedReason)

ingressCarrierInactive (maps to undefinedReason)

carrierOrigPcntExceeded (maps to undefinedReason)

carrierMaxUnitsExceeded (maps to undefinedReason)

destinationUnknown (maps to undefinedReason)

noRouteAvailable (maps to undefinedReason)

aliasesInconsistent

routeCallToSCN

resourcesUnavailable

genericDataReason

neededFeatureNotSupported

hopcountExceeded

incompleteAddress

Disengage Messages

Disengage messages are used to indicate that a party wants to end the call.

Request DRQ

This message is sent from the Cisco IOS Gatekeeper to the external application to indicate that an endpoint wants to end the call.

For Request DRQ, the possible tags are shown in Table 4-25:

Table 4-25 Request DRQ

Tag
Field Type
Mandatory or Optional
Corresponding RAS Message Field

c

GUID

Optional

DRQ:callIdentifier

C

GUID

Mandatory

DRQ:conferenceID

R

DRQ-reason

Mandatory

DRQ:disengageReason

A

Boolean

Mandatory

DRQ:answeredCall

S

Transport-Address

Mandatory

ARQ:srcCallSignalAddress. See Transport-Address.

T

clearToken

Optional

DRQ:tokens. See ClearToken.

g

GTD

Optional

DRQ:gtd. See GTD.

K

callCapacity

Optional

DRQ:capacity. See CallCapacity.

v

IA5String

Optional

DRQ:terminationCause:releaseCompleteCauseIE

r

IA5String

Optional

DRQ:terminationCause:releaseCompleteReason

v

IA5 String

Optional

DRQ:terminationCause:releaseCompleteCauseIE


Possible values for the DRQ-reason are:

forcedDrop

normalDrop

undefinedReason


Note All Request DRQ messages must contain Notification-only in the header. No response to this message is sent.


Resource Messages

Resource messages are used to indicate the current call capacity of the gateway.

Request RAI

This message is sent from the Cisco IOS Gatekeeper to the external application to indicate the call capacity and data rate of the gateway for H.323 calls.

For Request RAI, the possible tags are shown in Table 4-26:

Table 4-26 Request RAI

Tag
Field Type
Mandatory or Optional
Corresponding RAS Message Field

c

Transport-Address

Mandatory

RRQ:callSignalAddress. See Transport-Address.

r

Boolean

Mandatory

RAI:almostOutOfResources

K

callCapacity

Optional

RAI:capacity. See CallCapacity.



Note All Request RAI messages must contain Notification-only in the header. No response to this message is sent.


Bandwidth Messages

Bandwidth messages are used to request a change in bandwidth.

This section describes the following:

Request BRQ

Response BCF

Response BRJ

Request BRQ

This message is sent from the Cisco IOS Gatekeeper to the external application to request that an endpoint be allowed to change (increase or decrease) its bandwidth.

For Request BRQ, the possible tags are shown in Table 4-27:

Table 4-27 Request BRQ

Tag
Field Type
Mandatory or Optional
Corresponding RAS Message Field

i

Transport-Address

Mandatory

See Note. See Transport-Address.

b

Bandwidth

Mandatory

BRQ:bandWidth

C

GUID

Mandatory

BRQ:conferenceID

c

GUID

Mandatory

BRQ:callIdentifier

A

Boolean

Mandatory

BRQ:answeredCall



Note When sending a BRQ message, an endpoint identifies itself to the gatekeeper using the endpointIdentifier that it received from the gatekeeper in the RCF. Because this endpointIdentifier has only local significance to the gatekeeper and no significance to the server, the endpoint's CallSignalAddress is used here as an identifier.


Response BRQ

The server may modify the fields shown in Table 4-28 in the BRQ.

Table 4-28 Response BRQ

Tag
Field Type
Mandatory or Optional
Corresponding RAS Message Field

b

Bandwidth

Optional

BRQ:bandWidth

F

Boolean

Optional

None


Response BCF

This message is sent from the external application to the Cisco IOS Gatekeeper to confirm the request to allow an endpoint to change (increase or decrease) its bandwidth. This response gives the external application the opportunity to modify the Bandwidth field of a received LCF, but because the Cisco IOS Gatekeeper is not prepared to make changes in its bandwidth, any change in the BCF will automatically generate a BRJ back to the endpoint.

For Response BCF, the possible tag is shown in Table 4-29:

Table 4-29 Response BCF

Tag
Field Type
Mandatory or Optional
Corresponding RAS Message Field

b

Bandwidth

Mandatory

BCF:bandWidth


Response BRJ

This message is sent from the external application the Cisco IOS Gatekeeper to deny the request to allow an endpoint to change (increase or decrease) its bandwidth.

For Response BRJ, the possible tag is shown in Table 4-30:

Table 4-30 Response BRJ

Tag
Field Type
Mandatory or Optional
Corresponding RAS Message Field

R

BRJ-Reason

Mandatory

BRJ:rejectReason


Possible values for rejectReason are:

notBound

invalidConferenceID

invalidPermission

insufficientResource

invalidRevision

undefinedReason

securityDenial

Progress Messages

Progress messages provide information about the progress of a request. Progress messages include:

Response RIP

Request IRR

Request ALV

Response ALV

Response RIP

This message is sent from the external application to the Cisco IOS Gatekeeper when the external application cannot immediately process the request. This message indicates that the request is in progress (RIP) and that additional time is needed. When the Cisco IOS Gatekeeper receives this message, it forwards a request to the H.323 endpoint indicating that an extension of the timeout is required. The external application can send more that one Response RIP as is needed to process the request.

For Response RIP, the possible tag is shown in Table 4-31:

Table 4-31 Response RIP

Tag
Field Type
Mandatory or Optional
Corresponding RAS Message Field

d

Integer

Mandatory

RIP:delay


Possible values of the delay are 1 through 65535 milliseconds.

Request IRR

This message is sent to the GK and contains details for the call after a successful connect. A Request IRR message is sent at both the originating and terminating side of the call. If both legs reference the same GK, only one Request IRR is sent. The GK sends information for only one call in each Request IRR message.

Table 4-32 shows the new Request IRR tags:

Table 4-32 New Request IRR Tags

Tag
Field Type
Mandatory or Optional
Corresponding RAS Message Field

S

Transport-Address

Mandatory

IRR:srcCallSignalAddress. See Transport-Address.

P

PerCallInfo

Optional

IRR:perCallInfo. See PerCallInfo.

K

callCapacity

Optional

IRR:capacity. See CallCapacity.


Request ALV

The REQUEST ALV is sent from the Gatekeeper to a GKTMP server on the detection of slower response or server failure.

This message does not contain any parameters in its body.

Response ALV

This message is returned in response to a REQUEST ALV message and does not contain any parameters in its body.

Trigger Registration Messages

Trigger registration messages are used by external applications to inform the Cisco IOS Gatekeeper which RAS messages are interesting to the external application. Interesting RAS messages trip a trigger in the Cisco IOS Gatekeeper and cause the Cisco IOS Gatekeeper to send a GKTMP RAS message to the external application.

As with the GKTMP RAS messages, trigger registration messages have the following format:

Single message line

One or more message header lines

Blank line, which separates the message header from the message body

Zero or more message body lines

Message Line

There are two types of trigger registration messages: register and unregister.

The first line of each trigger registration request/response message uses the format:

REGISTER RAS_message_type

The first line of each trigger unregistration request/response message uses the format:

UNREGISTER RAS_message_type

Possible RAS message types are as follows:

RRQ—Registration request

URQ—Unregistration request

ARQ—Admission request

LRQ—Location request

LCF—Location confirm

LRJ—Location reject

DRQ—Disengage request

RAI—Resource availability information

BRQ—Bandwidth request

Message Header

The message line is immediately followed by the message header. Each message header contains a field name and a value, separated by a colon (field:value). Possible fields are shown in Table 4-33:

Table 4-33 Message Header Fields 

Field Names
Field Values

Version-ID

Version of the GKTMP. The version ID consists of a major number (gk_major) and a minor number (gk_minor). For example, Version 1 is represented as 100.

From

String that identifies the originator of the message. For trigger registration requests from the external application, this field contains the server ID. For trigger registration responses from the Cisco IOS Gatekeeper, this field contains the gatekeeper ID. This field is required for trigger registration and unregistration requests and responses.

To

String that identifies the receiver of the message. For trigger registration requests from the external application, this field contains the gatekeeper ID. For trigger registration responses from the Cisco IOS Gatekeeper, this field contains the ID of the external application that initiated the request. This field is required for trigger registration and unregistration requests and responses.

Priority

A number indicating the priority of this trigger in relation to other triggers for the same RAS message type. Possible values are 1 through 20. 1 is the highest priority.

If the Cisco IOS Gatekeeper has a registration for a RAS message type and receives another registration for the same RAS message from the same external application with the same priority, the Cisco IOS Gatekeeper uses the new registration and discards the previous one. If the Cisco IOS Gatekeeper has a registration for a RAS message type and receives another registration with the same priority from a different external application, the Cisco IOS Gatekeeper discards the new registration. This field is required for trigger registration and unregistration requests and is echoed in trigger registration and unregistration responses.

Content-length

The number of octets contained in the message body. If the message body is null, this field is omitted. This field is used only in trigger registration requests.

Notification-only

None. No value is included after the colon. If this field name is present, it indicates to the Cisco IOS Gatekeeper that it should forward requests for the specified RAS messages as a notification only. This field is used only in trigger registration requests.

Status

String that indicates the response code from the Cisco IOS Gatekeeper. This field is used only in trigger registration and unregistration responses.

Possible response codes for unregistration requests are:

success—The registration has been accepted.

invalidPriority—The registration has been rejected because the Gatekeeper already has a registration for this RAS message type with the same priority from another application.

invalidFilters—Parsing of the message body failed.

invalidGKID—The gatekeeper ID specified in the "To" field of the request does not match the ID of any gatekeepers on this Cisco router.

Possible response codes for unregistration responses are:

success—The unregistration has been accepted.

invalidPriority—The unregistration has been rejected because the Gatekeeper does not have a registration for this RAS message type with the same priority from this application.

invalidGKID—The gatekeeper ID specified in the "To" field of the request does not match the ID of any gatekeepers on this Cisco router.


The message header is followed immediately by a blank line.

Message Body

The message body follows the blank line. Only trigger registration requests contain a message body. Trigger registration responses, unregistration requests, and unregistration responses end after the blank line.

The message body in a trigger registration request can be used to narrow the circumstances under which the Cisco IOS Gatekeeper sends a REQUEST xxx to the external application. In this case, the external application includes tags and values in the message body that if matched will trigger the Cisco IOS Gatekeeper to generate a REQUEST xxx.

The tags that can be included vary depending on the RAS message type, and are a subset of the types that can be included in GKTMP RAS messages.

For the field type of Alias-Address, trailing wildcards can be used with E.164 addresses. An asterisk can be used to indicate a string of characters (for example, 1800*). A period can be used to indicate a single character (for example, 1800.......).


Note Wildcards cannot be used at the beginning or in the midst of a value, only at the end. If you include a wildcard at the beginning or in the midst of a value, it will be interpreted as a literal character.


Register RRQ and RAI

For Register RRQ and RAI, the tags shown in Table 4-34 can be used to filter messages:

Table 4-34 Register RRQ and RAI

Tag
Field Type
Mandatory or Optional
Corresponding RAS Message Field

t

Endpoint-Type

Optional

RRQ:terminalType

p

Supported-Prefix

Optional

RRQ:terminalType:gateway:protocol:*:supportedPrefixes

S

Boolean

Optional

 

Register URQ

For Register URQ, the tags shown in Table 4-35 can be used to filter messages:

Table 4-35 Register URQ

Tag
Field Type
Mandatory or Optional
Corresponding RAS Message Field

t

Endpoint-Type

Optional

RRQ:terminalType

p

Supported-Prefix

Optional

RRQ:terminalType:gateway:protocol:*:supportedPrefixes


Register ARQ, DRQ, IRR, and BRQ

For Register ARQ, DRQ, IRR, and BRQ the tags shown in Table 4-36 can be used to filter messages:

Table 4-36 Register ARQ, DRQ, IRR, and BRQ

Tag
Field Type
Mandatory or Optional
Corresponding RAS Message Field

d

Alias-Address

Optional

ARQ:destinationInfo

E

integer

Optional

ARQ:nonStandardData:redirectReason


Register LRQ

For Register LRQ, the tags shown in Table 4-37 can be used to filter messages:

Table 4-37 Register LRQ

Tag
Field Type
Mandatory or Optional
Corresponding RAS Message Field

d

Alias-Address

Optional

LRQ:destinationInfo

E

integer

Optional

LRQ:nonStandardData:redirectReason



Note A gatekeeper might not be the final destination of the LRQ messages that it receives. If the queried address in an LRQ is in another Gatekeeper's zone, the LRQ is forwarded to that gatekeeper and is not resolved locally. This means that there might not be a local zone that can be associated with the LRQ. To address this situation, the gatekeeper arbitrarily uses the server registrations for the first configured local zone. Because the order in which configured zones appear can change with deletions and additions, servers should send identical LRQ registrations to all zones (all logical gatekeepers) on the same router.


Register LCF

For Register LCF, the tags shown in Table 4-38 can be used to filter messages:

Table 4-38 Register LCF

Tag
Field Type
Mandatory or Optional
Corresponding RAS Message Field

d

Alias-Address

Optional

LRQ/LCF:destinationInfo

X

Alias-Address

Optional

LCF:remoteExtensionAddress


Register LRJ

For Register LRJ, the tag shown in Table 4-39 can be used to filter messages:

Table 4-39 Register LRJ

Tag
Field Type
Mandatory or Optional
Corresponding RAS Message Field

d

Alias-Address

Optional

LRQ:destinationInfo


Additional Messages

GTD

The Generic Transparency Descriptor (GTD) field type is a structure comprising of two sub-fields: length and data. This field type is required for values that contain <cr><lf> pairs in its body. The length (B) sub-field indicates the size of the data sub-field and indicates to the parser that any occurrence of <cr><lf> within the data sub-field is not a <tag>=<value> delimiter.

Table 4-40 shows the new GTD tags:

Table 4-40 New GTD Tags

Tag
Field Type
Mandatory or Optional
Corresponding RAS Message Field

B

IA5String

Mandatory

Length of the data sub-field. Contains 5-digit ASCII characters.

Data

subfield

Mandatory

Opaque data transported by GKTMP.


Usage Notes

The GTD field type is different from other GKTMP fields in that <cr><lf> does not indicate the end of the GTD line. The following rules must be followed in processing the GTD field type:

Use `g' as a GTD tag across all REQUEST and RESPONSE messages.

The length of the GTD data sub-field is specified by `B' and is represented by five ASCII digits.

A `B' sub-field is delimited by `:'.

<cr><lf> or <lf> within the GTD body should not be interpreted as a tag or value delimiter. The <cr><lf> after the GTD sub-field—specified by length sub-field—is the delimiter.

The GTD field should not be included in any tag other than `g'.

Gatekeeper to Server:

`g=B:<Five ASCII digits>:<data>' should be used to send the GTD.

`g=' is illegal.

The absence of a `g' tag indicates there is no GTD data.

All other `g' tag formats are illegal

Server to Gatekeeper:

The `g' tag can only be sent in a RESPONSE message corresponding to a REQUEST message from the gatekeeper in which a GTD is present. The server cannot generate and send a GTD if it has not received a GTD from the gatekeeper.

`g=B:<Five ASCII digits>:<data>' indicates the server is returning the GTD it received in a request from the gatekeeper. (This GTD could be a modified version of gatekeeper GTD.) The gatekeeper should replace its cached copy of the GTD with the received copy of the GTD.

`g=' indicates that server wants the gatekeeper to retain its copy of the GTD.

The absence of a `g' tag indicates that the gatekeeper should delete its copy of GTD.

The gatekeeper should not send a `g' tag or value if the server GKTMP version is less than version 4.1. Versions below version 4.1 cannot interpret the GTD and <cr><lf> may not delimit the GTD tagor value, so these lower versions cannot to skip the `g' tag line.

Format

g=B:<Length in 5 ASCII digits>:<Data>

Example

g=B:00003:1AB

AlternateGK

A message body line containing a field of type AlternateGK contains a set of fields enclosed within curly braces "{ }". Each of the fields within the curly braces are identified by a tag, with each field separated by SP (ascii space, 0x20) characters.

Table 4-41 shows the AlternateGK tags:

Table 4-41 AlternateGK Tags

Tag
Field Type
Mandatory or Optional
Corresponding RAS Message Field

r

Transport-Address

Mandatory

AlternateGK:rasAddress. See Transport-Address.

g

Alias-Address

Optional

AlternateGK:gatekeeperIdentifier. See Alias-Address.

n

Boolean

Mandatory

AlternateGK:needToRegister

p

integer

Mandatory

AlternateGK:priority


FromReplyAddress

The from IP address is the address from which an LRQ message was received. The reply-to address is the mandatory IP address specified in the RAS LRQ message replyAddress field. A GKTMP application can use these fields to authenticate the source of LRQ message.

Table 4-42 shows the FromReplyAddress tags:

Table 4-42 FromReplyAddress Tags

Tag
Field Type
Mandatory or Optional
Corresponding RAS Message Field

f

IP address

Mandatory

Address of the gatekeeper from which this LRQ message was received.

r

IP address

Mandatory

LRQ::replyAddress:ipAddress:ip


ServiceControlSession

Table 4-43 shows the new Service Control Session tags:

Table 4-43 New ServiceControl Sessions Tags

Tag
Field Type
Mandatory or Optional
Corresponding RAS Message Field

d

IA5String

Optional

serviceControl:contents

r

IA5String

Mandatory

serviceControl:reason

s

Integer

Mandatory

serviceControl:sessionId


CallCapacity

The CallCapacity message indicates the ability of the gateway to accept each type of call the gateway supports, such as voice calls.

Table 4-44 shows the CallCapacity tags:

Table 4-44 CallCapacity Tags

Tag
Field Type
Mandatory or Optional
Corresponding RAS Message Field

T

CallCapacityType

Mandatory

xRQ::callCapacity:maximum/currentCallCapacity:xxxxGwCallsAvailable

G

IA5String

Mandatory

xRQ::callCapacity:maximum/currentCallCapacity:xxxxGwCallsAvailable:group

C

Integer

Mandatory

xRQ::callCapacity:maximumCallCapacity:xxxxGwCallsAvailable:calls

c

Integer

Mandatory

xRQ::callCapacity:currentCallCapacity:xxxxGwCallsAvailable:calls


CarrierInfo

The gatekeeper sends incoming carrier information received in a RAS ARQ message from the gateway to an external GKTMP application. This information allows the application to select an outbound carrier and remote zones that the carrier may exist in. The gatekeeper uses this outbound carrier and zone information to query for the egress gateway.

Table 4-45 shows the new Carrier Information tags:

Table 4-45 CarrierInfo Tags

Tag
Field Type
Mandatory or Optional
Corresponding RAS Message Field

i

IA5String

Mandatory

destination carrierID

p

Integer

Optional

Priority of this carrier

z

remoteZone

Optional

Remote zone information. See RemoteZone.


TrunkGroupInfo

Table 4-46 shows the new Trunk Group Information tags:

Table 4-46 TrunkGroupInfo Tags

Tag
Field Type
Mandatory or Optional
Corresponding RAS Message Field

i

IA5String

Mandatory

Destination trunk group

p

Integer

Optional

Priority of this trunk group

z

remoteZone

Optional

Remote zone information. See RemoteZone.


Alias-Address

A field of type Alias-Address contains a sequence of aliases separated by SP (ascii space, 0x20) characters. Each alias is prefixed by one of the following type characters, followed by a colon:

H: an H.323-ID

E: an E.164 address

M: an email ID

For example, in an RRQ message, a terminal alias containing the sequence of an H.323-ID of "John Smith", an E164 address of 4085551212, and an email-id of "jsmith@somewhere.com" is indicated by the line: a=H:"John Smith" E:4085551212 M:jsmith@somewhere.com

PerCallInfo

If the message contains a PerCallInfo field, the following fields shown in Table 4-47 are included:

Table 4-47 PerCallInfo Fields

Tag
Field Type
Mandatory or Optional
Corresponding RAS Message Field

c

GUID

Optional

IRR:perCallInfo:callIdentifier

C

GUID

Mandatory

IRR:perCallInfo:conferenceID

A

Boolean

Optional

IRR:perCallInfo:originator

b

Bandwidth

Mandatory

IRR:perCallInfo:bandwidth

t

System Time

Optional

IRR:perCallInfo:NonStandard:start_time

s

IA5String

Optional

IRR:perCallInfo:tokens:IZCT:srcZone

d

IA5String

Optional

IRR:perCallInfo:tokens:IZCT:dstZone

S

IA5String

Optional

IRR:perCallInfo:srcCarrierId

D

IA5String

Optional

IRR:perCallInfo:dstCarrierId


RemoteZone

Table 4-48 shows the remoteZone field tags:

Table 4-48 RemoteZone Tags

Tag
Field Type
Mandatory or Optional
Description

r

Transport-Address

Mandatory

RAS address of the zone. See Transport-Address.

c

Integer

Optional

Cost value associated with the zone

p

Integer

Optional

Priority value associated with the zone

T

clearToken

Optional

ARQ:tokens. See ClearToken.


Transport-Address

The only type of transport address currently supported by the gatekeeper is IP version 4. However, a type prefix is defined for future extensibility. For example, I: IP version 4 address.

The address is specified in the usual dotted string form, followed by a colon and port number. For example, the callSignalAddress in an RRQ message may be specified as: c=I:172.21.137.4:1720.

ClearToken

If the message contains a clearToken field, the fields shown in Table 4-49 are included:

Table 4-49 ClearToken Fields

Tag
Field Type
Mandatory or Optional
Corresponding RAS Message Field

O

OBJECT-IDENTIFIER

Mandatory

tokens:objectIdentifier

p

IA5string

Optional

tokens:password

t

integer

Optional

tokens:timestamp

s

IA5string

Optional

tokens:challengeString

r

integer

Optional

tokens:random

G

IA5string

Optional

tokens:generalID

o

OBJECT-IDENTIFIER

Optional

tokens:nonStandard:objectIdentifier

d

IA5string

Optional

tokens:nonStandard:data


CryptoToken

If the message contains a cryptoToken field, the additional fields shown in Table 4-50 are included:

Table 4-50 CryptoToken Fields

Tag
Field Type
Mandatory or Optional
Corresponding RAS Message Field

H

IA5string

Optional

CryptoToken:alias

t

IA5string

Optional

CryptoToken:timestamp

h

IA5string

Optional

CryptoToken:token