03.823GPPCall Forwarding (CF) Supplementary ServicesStage 2TS
The present document gives the stage 2 description of the call forwarding supplementary services.
The group of supplementary services call offering supplementary services is divided into 4 different supplementary services:
– Call forwarding unconditional (CFU) (clause 1);
– Call forwarding on mobile subscriber busy (CFB) (clause 2);
– Call forwarding on no reply (CFNRy) (clause 3);
– Call forwarding on mobile subscriber not reachable (CFNRc) (clause 4).
The following documents contain provisions which, through reference in this text, constitute provisions of the present document.
- References are either specific (identified by date of publication, edition number, version number, etc.) or non‑specific.
- For a specific reference, subsequent revisions do not apply.
- For a non-specific reference, the latest version applies.
- A non-specific reference to an ETS shall also be taken to refer to later versions published as an EN with the same number.
- For this Release 1998 document, references to GSM documents are for Release 1998 versions (version 7.x.y).
 GSM 01.04: "Digital cellular telecommunications system (Phase 2+); Abbreviations and acronyms".
 GSM 02.04: "Digital cellular telecommunications system (Phase 2+); General on supplementary services".
 GSM 02.78: "Digital cellular telecommunications system; Customised Applications for Mobile network Enhanced Logic (CAMEL); Service definition – Stage 1"
 GSM 02.82: "Digital cellular telecommunications system (Phase 2+); Call Forwarding (CF) Supplementary Services ‑ Stage 1".
 GSM 03.11: "Digital cellular telecommunications system (Phase 2+); Technical realization of supplementary services".
 GSM 03.15: "Digital cellular telecommunications system (Phase 2+); Technical realization of operator determined barring".
 GSM 03.78:"Digital cellular telecommunications system; Customised Applications for Mobile network Enhanced Logic (CAMEL) Phase 2; Stage 2"
Abbreviations used in the present document are listed in GSM 01.04.
0.3 The forwarded-to number
As indicated in GSM 02.82 the forwarded-to numbers are stored in the international format. If according to GSM 02.78 the served subscriber is provided with a Translation Information Flag (TIF-CSI) then the HPLMN shall treat the forwarded-to number transparently at the time of registration, i.e. not perform any checks or translations. In this case the forwarded-to number shall be stored in the format as it was received from the MS.
Therefore, if transferred, the forwarded-to number is transferred from the HLR to other network entities and stored in the VLR always in the format as stored in the HLR.
0.4 Cross phase compatibility
For the following supplementary services, a number of changes exist between the present document and the Phase 1 specification:
– Call forwarding unconditional;
– Call forwarding on mobile subscriber busy;
– Call forwarding on no reply;
– Call forwarding on mobile subscriber not reachable.
The main body of the present document assumes that all network entities comply with this version of the service. In each case an additional subclause (subclause x.6) defines the additional requirements for when one or more network entities or the MS complies with the Phase 1 specifications for the supplementary service procedures.