8 Interaction with other supplementary services

03.933GPPStage 2Technical realization of Completion of Calls to Busy Subscriber (CCBS)TS

GSM 02.93 specifies a number of interactions between CCBS and other supplementary services. Additional details of how these interactions apply are as follows.

8.1 Call forwarding unconditional (CFU)

If a call to destination B is forwarded to subscriber C by CFU and MS C is NDUB, the GMSC shall inform MSC A that CCBS is not possible when it releases the call. Refer to Process MT_GMSC (see GSM 03.18) for further details.

If destination B activates CFU after subscriber A has activated a CCBS Request against destination B, HLR B shall not process CCBS Requests in the queue which are related to the relevant Basic Service Group, except that T7 shall continue for each CCBS Request in the destination B queue. If T7 expires for a particular request, HLR B shall cancel the request, as described in the SDLs shown in figure 11.2.2.1.

If MSC B is monitoring MS B when CFU is activated by destination B and all the CCBS Requests in the destination B queue subsequently become "Active and Quiescent", then HLR B shall send “Stop Reporting” to MSC B. If destination B deactivates CFU resulting in one or more requests becoming "Active and Operative" in the destination B queue then, HLR B shall send “Start Reporting” to MSC B if monitoring is not already ongoing.

A CCBS Call shall be forwarded without the CCBS call Indicator.

8.2 Call forward on busy (CFB)

If a call to destination B is forwarded to subscriber C by CFB and MS C is NDUB, the forwarding switch (GMSC or VMSC) shall inform MSC A that CCBS is possible when it releases the call. Refer to Process MT_GMSC or Process ICH_MSC (see GSM 03.18) for further details.

If destination B activates CFB after subscriber A has activated a CCBS Request against destination B, HLR B shall continue to process CCBS Requests in the queue. If a CCBS Call subsequently arrives at MSC B and MS B is NDUB, a network provider option exists as to whether:

– the CCBS call shall be treated as when MS B is busy for the CCBS call, without CFB active; or

– the CCBS call shall be forwarded without the CCBS call Indicator.

8.3 Call forwarding on no reply (CFNRy)

If a call to destination B is forwarded to subscriber C by CFNRy and MS C is NDUB, the forwarding switch (VMSC) shall inform MSC A that CCBS is not possible when it releases the call. Refer to Process MT_GMSC or Process ICH_MSC (see GSM 03.18) for further details

If destination B activates CFNRy after subscriber A has activated a CCBS Request against destination B, HLR B shall continue to process CCBS Requests in the queue.

A CCBS call shall be forwarded without the CCBS call Indicator.

8.4 Call forwarding on MS not reachable (CFNRc)

If a call to destination B is forwarded to subscriber C by CFNRc and MS C is NDUB, the forwarding switch (GMSC or VMSC) shall inform MSC A that CCBS is not possible when it releases the call. Refer to Process MT_GMSC or Process_ICH_MSC (see GSM 03.18) for further details.

If destination B activates CFNRc after subscriber A has activated a CCBS Request against destination B, HLR B shall continue to process CCBS Requests in the queue.

The CCBS call shall be forwarded without the CCBS call Indicator.

8.5 Call Waiting (CW)

No impact.

8.6 Multiparty service (MPTY)

No impact.

8.7 Closed user group (CUG)

No impact.

8.8 Advice Of Charge (AoC)

If subscriber A accepts a "CCBS Recall" indication but ACMmax exceeds, then MSC A shall cancel the associated request and shall not establish the CCBS Call.

8.9 Barring of all outgoing calls (BAOC)

If subscriber A accepts a "CCBS Recall" indication but MSC A detects that BAOC is active and operative, then MSC A shall cancel the associated request and shall not establish the CCBS Call.

8.10 Barring of outgoing international calls (BOIC)

If subscriber A accepts a "CCBS Recall" indication but the CCBS Call would be an international call and MSC A detects that BOIC is active and operative, then MSC A shall cancel the associated request and shall not establish the CCBS Call.

8.11 Barring of outgoing international calls except those directed to the home PLMN country (BOIC-exHC)

If subscriber A accepts a "CCBS Recall" indication but the CCBS Call would be an international call except to the home PLMN country and MSC A detects that BOIC-exHC is active and operative, then MSC A shall cancel the associated request and shall not establish the CCBS Call.

8.12 Barring of all incoming calls (BAIC)

If a CCBS Request arrives at HLR B and HLR B detects that BAIC is active and operative for the relevant Basic Service Group, then HLR B shall not accept the activation attempt and shall indicate short term denial in the response.

If MSC B is monitoring MS B when BAIC is activated by destination B then all the CCBS Requests in the destination B queue subsequently become "Active and Quiescent" and HLR B shall send "Stop Reporting" to MSC B. If destination B deactivates BAIC resulting in one or more requests becoming "Active and Operative" in the destination B queue then, HLR B shall send “Start Reporting” to MSC B if monitoring is not already ongoing.

If barring of all incoming calls becomes active and operative for a particular Basic Service Group for destination B, such that a CCBS call from subscriber A is not permitted, HLR B shall cancel the associated request related to the Basic Service Group and select the next non-suspended request in the queue for processing for other Basic Service Groups.

8.13 Barring of incoming calls when roaming outside the home PLMN country (BIC-Roam)

If a CCBS Request arrives at HLR B and HLR B detects that BIC-Roam is active and operative for the relevant Basic Service Group, then HLR B shall not accept the activation attempt and shall indicate short term denial in the response.

If MSC B is monitoring MS B when BIC-Roam is activated by destination B then all the CCBS Requests in the destination B queue subsequently become "Active and Quiescent" and HLR B shall send "Stop Reporting" to MSC B. If destination B deactivates BIC-Roam resulting in one or more requests becoming "Active and Operative" in the destination B queue then, HLR B shall send "Start Reporting" to MSC B if monitoring is not already ongoing.

If barring of incoming calls when roaming outside the home PLMN country becomes active and operative for a particular Basic Service Group for destination B, such that a CCBS call from subscriber A is not permitted, HLR B shall cancel the associated request related to the Basic Service Group and select the next non-suspended request in the queue for processing for other Basic Service Groups.

8.14 Completion of calls to busy subscriber (CCBS)

Subscriber A may have successfully activated one or more CCBS requests against different destinations B, and also have one or more CCBS requests successfully activated against him by different subscribers. In this case, HLR A shall co-ordinate the different requests.

Checking for an identical CCBS request already existing shall include checks in both directions, i.e. if subscriber A activates a CCBS Request against destination B, HLR A shall check subscriber A’s originating queue for any previous requests activated by subscriber A against destination B for the same basic service group. HLR A shall also check subscriber A’s target queue for any requests activated by destination B against subscriber A for the same basic service group.