4 Communication Hold (HOLD)

24.4103GPPCommunication HOLD (HOLD) PSTN/ISDN simulation servicesNGN Signalling Control ProtocolProtocol specificationRelease 8TISPANTS

4.1 Introduction

Not applicable.

4.2 Description

4.2.1 General description

The Communication Hold supplementary service enables a user to suspend the media stream(s) of an established IP multimedia session, and resume the media stream(s) at a later time.

4.3 Operational requirements

4.3.1 Provision/withdrawal

The HOLD service that includes announcements shall be provided after prior arrangement with the service provider.

4.3.2 Requirements on the originating network side

No specific requirements are needed in the network.

4.3.3 Requirements in the network

No specific requirements are needed in the network.

4.3.4 Requirements on the terminating network side

No specific requirements are needed in the network.

4.4 Coding requirements

No specific coding requirements are needed.

4.5 Signalling requirements

4.5.1 Activation/deactivation

The HOLD service is activated at provisioning and deactivated at withdrawal.

Not applicable.

4.5.1A Registration/erasure

The HOLD service requires no registration. Erasure is not applicable.

4.5.1B Interrogation

Interrogation of HOLD is not applicable.

4.5.2 Invocation and operation

4.5.2.1 Actions at the invoking UE

In addition to the application of basic call procedures according to ES 283 003 [1] the following procedures shall be applied at the invoking UE in accordance with RFC 3264 [4].

A UE shall not invoke the HOLD service on a dialog associated with an emergency call the UE has intitiated.

If individual media streams are affected:

  • for each media stream that shall be held, the invoking UE shall generate a new SDP offer that contains:
  • an "inactive" SDP attribute if the stream was previously set to "recvonly" media stream; or
  • a "sendonly" SDP attribute if the stream was previously set to "sendrecv" media stream; or
  • for each media stream that shall be resumed, the invoking UE shall generate a new SDP offer that contains:
  • a "recvonly" SDP attribute if the stream was previously an inactive media stream; or

– a "sendrecv" SDP attribute if the stream was previously a sendonly media stream, or the attribute may be omitted, since sendrecv is the default.

If all the media streams in the SDP are affected:

  • for the media streams that shall be held, the invoking UE shall generate a session level direction attribute in the SDP that is set to:
  • "inactive" if the streams were previously set to "recvonly" media streams; or
  • "sendonly" if the streams were previously set to "sendrecv" media streams; or
  • for the media streams that shall be resumed, the invoking UE shall generate a session level direction attribute in the SDP that is set to:
  • "recvonly" if the streams were previously inactive media streams; or

– "sendrecv" if the streams were previously sendonly media streams, or the attribute may be omitted, since sendrecv is the default.

Then the UE shall send the generated SDP offer in a re-INVITE (or UPDATE) request to the held UE.

4.5.2.2 Actions at the P-CSCF of the invoking UE

Basic communication procedures according to ES 283 003 [1] shall apply.

4.5.2.3 Actions at the S-CSCF

Basic communication procedures according to ES 283 003 [1] shall apply.

4.5.2.4 Actions at the AS of the invoking UE

As a network option the AS of the invoking UE shall initiate the procedures for the provision of an announcement to the held user in accordance with TS 183 028 [6].

4.5.2.5 Actions at the incoming I-CSCF

Basic communication procedures according to ES 283 003 [1] shall apply.

4.5.2.6 Actions at the outgoing IBCF

Basic communication procedures according to ES 283 003 [1] shall apply.

4.5.2.7 Actions at the incoming IBCF

Basic communication procedures according to ES 283 003 [1] shall apply.

4.5.2.8 Actions at the P-CSCF of the held UE

Basic communication procedures according to ES 283 003 [1] shall apply.

4.5.2.9 Actions at the held UE

Basic communication procedures according to ES 283 003 [1] shall apply.

4.6 Interaction with other services

4.6.1 Communication Hold (HOLD)

No impact, i.e. neither service shall affect the operation of the other service.

4.6.2 Terminating Identification Presentation (TIP)

No impact, i.e. neither service shall affect the operation of the other service.

4.6.3 Terminating Identification Restriction (TIR)

No impact, i.e. neither service shall affect the operation of the other service.

4.6.4 Originating Identification Presentation (OIP)

No impact, i.e. neither service shall affect the operation of the other service.

4.6.5 Originating identification restriction (OIR)

No impact, i.e. neither service shall affect the operation of the other service.

4.6.6 Conference calling (CONF)

If a participant of a conference invokes the HOLD service, it is not desirable to provide an announcement to the conference. Therefore if a communication to a remote URI shall be held by sending a re-INVITE (or UPDATE) request which includes the "isfocus" feature parameter in the Contact header, the AS of the invoking UE shall not initiate the procedures for the provision of an announcement to the held user.

4.6.7 Communication DIVersion services (CDIV)

No impact, i.e. neither service shall affect the operation of the other service.

4.6.8 Malicious Communication IDentification (MCID)

No impact, i.e. neither service shall affect the operation of the other service.

4.6.9 Anonymous Communication Rejection and Communication Barring (ACR/CB)

No impact, i.e. neither service shall affect the operation of the other service.

4.6.10 Explicit Communication Transfer (ECT)

No impact, i.e. neither service shall affect the operation of the other service.

4.7 Interactions with other networks

4.7.1 Interaction with PSTN/ISDN

The procedures of ETSI TS 129 163 [3], clause 7.4.10 shall apply with the additions of ES 283 027 [2].

NOTE: If the Hold and Resume procedures are initiated from the PSTN/ISDN network side, only the UPDATE request is used to signal the new SDP, in accordance with ES 283 003 [1].

4.7.2 Interaction with PSTN/ISDN Emulation

For Further Study.

4.7.3 Interaction with external IP networks

The procedures of ES 283 003 [1] shall apply.

4.8 Parameter values (timers)

Not applicable.

Annex A (informative):
Signalling Flows