General Considerations for CTS phase 1:

10.563GPPProject scheduling and open issues: GSM Cordless Telephony System CTS, Phase 1TS

Decisions at SMG


1. A work item proposal “GSM COMPATIBLE HOME BASE SYSTEM” is presented at SMG#21 (Tdoc 88/97).

2. It is decided, that the matter is studied by SMG 1, SMG 2, SMG 3, SMG 9 and SMG 10 and to report at
SMG #22. SMG 1 should co-ordinate the feasibility study (Tdoc 287/97).


1. The concept has been considered to be feasible. The feasibility study report and updated WID has been presented (Tdoc 382/97).

2. The work item is approved at SMG#22. The title is “GSM – Cordless Telephony System (CTS)”


1. The CTS work item status and schedule is presented (Tdoc 811/97)

2. The following working assumptions are taken by SMG#23 in order to proceed on the stage 1 work:
– operation of CTS is tied to a GSM subscription
– CTS is to operate in the spectrum of the home network of that subscription

3. The working assumption of SMG7, that both the CTS mobile station and the CTS fixed part should be considered as terminals, was confirmed by SMG#23


Only UMTS and release 97 WI’s on the agenda.


1. The CTS work item status and schedule has been presented (Tdoc 049/98). a conclusion was that the release of the CTS WI is expected for SMG#27 now.


  1. Each STC presented the CTS status and the work progress.
  2. The CTS radio basic assumptions were presented within the SMG2 report and endorsed by the SMG#26.
  3. CTS Stage 1 was distributed for information.

Decisions on CTS Service Requirements

Responsible body: SMG STC SMG1. The list of high level requirements is contained in ANNEX A.1 and has emerged from the following meetings:

1. SMG1 CTS ad hoc meeting in Lund/Sweden 27.- 28. August 1997
a first draft version 0.1.1 has been elaborated

2. SMG1 plenary in Dresden/Germany 3. – 7. November 1997 a reworked version 0.3.0 has bee agreed which takes comments of SMG3-SA into account (Tdoc SMG3-SA 315/97)

3. SMG1/SMG10 CTS ad hoc meeting Nuremberg/Germany 10. – 11. December 1997 a new version 0.5.0 has been agreed as input for the next SMG1. This version takes comments of SMG3-SA and SMG2 into account (Tdoc SMG3-SA 420/97, Tdoc SMG2 402/97, Tdoc SMG2 WPB 146/97) The features not considered for CTS phase 1 are moved to the Annex A.2 (Issues for later phases of CTS)

4. SMG1 plenary in Sophia Antipolis 12. – 16. January 1998 has discussed CTS in several ad hoc groups during the meeting. As a result a stable version has of the CTS stage 1 service description has been agreed, however due to editorial needs a version 1.0.1 was prepared after the meeting and accepted by e-mail in order to have this version ready for presentation at SMG#25 (Tdoc SMG1 141/98).

  1. SMG10 WPB at SMG10 plenary 4.-6. February in Worcester has reviewed and updated the CTS security requirements. In order to have a full view on CTS stage 1 at the SMG#25 plenary, the result is sent as liaison statement to SMG1 and to SMG#25 plenary (Tdoc SMG10 073/98).
  2. SMG1 Plenary in Naantali 6-10. July 98 has briefly discussed about CTS. Several comments was proposed and approved. The CTS stage 1 has been upgraded according to these comments.
  3. On SMG1 demand, SMG12 has reviewed the last CTS stage 1. SMG12 # 3 has considered the stage 1 stable enough to be presented to SMG #27.

Decisions on CTS stage 2

1. A decision on the CTS Radio Interface lower layer concept has been reached by SMG2 WPB meeting in April. The concept is transformed in a description of the physical aspects of the radio interface for completion of the CTS stage 2 description and will be presented at SMG2 plenary in May.

2. SMG10 has installed a number of CTS ad hoc meetings on CTS security in order to reach a stable status of the CTS overall CTS security aspects at the SMG10 plenary in April.

3. The first SMG 10 CTS ad hoc has fixed the main issues of CTS local security aspects (authentication of between the Mobile Station and the CTS Fixed Part, etc.) and pointed out the requirements for the implementation of the CTS supervising security (secure operation and subscription control of the CTS).

4. The second SMG10 CTS ad hoc meeting has fixed the principals for the PLMN security apects of CTS.

  1. SMG12 #1 has introduced a CTS reference model making a clear split between the subscription given in by the HPLMN operator and the frequency usage given by the DPLMN (Donor PLMN operator). (Tdoc SMG12 176/98). The reference model has to be studied in detail and is requested to be adapted by other STCs.
  2. SMG12 #3 has introduced the CTS role model and the coverage scenario. It was agreed to produce a stabilised Stage 2 at the SMG12 #4 in September.

Funding of CTS security algorithms

  1. Funding for CTS algorithms has been discussed at the SMG10 plenary in Worcester 4.-6. February 1998.
    The call for a funding group of potential CTS manufactures has been summarised in Tdoc SMG10 077/98.
  2. The terms of reference for the SAGE work have been approved by ETSI board #13.

Co-operation with ETSI TC-ERM:

  1. As decided at SMG#23 (Tdoc 874/97), liaison functions from SMG to ERM on CTS should be established in order to provide information about the work item CTS. A presentation of the stage 2 regarding the CTS radio interface with emphasise on the frequency usage will be held by delegates of SMG2 WPB.
  2. CTS subject was presented by SMG2 delegates to ERM/RM the 8th of June. It was agreed that no new spectrum allocation is needed for CTS.

Support tools for specification work

ETSI FTP Server ( or

Meeting reports of the involved STCs SMG1, SMG2, SMG 3, (SMG 4), SMG 7, SMG 9, SMG 10

Work item rapporteurs based on the WID

SMG1 Mikael Dahlkvist, Ericsson

SMG2 Philippe Desblancs, Alcatel

SMG3 Jean Francois Rubon, Alcatel

(SMG4 Peter Edlund, Ericsson)

SMG7 Sada Dia, Alcatel

SMG9 Kerstin Litzén, Ericsson

SMG10 Samira Messiet, Alcatel

SMG12 Michael Roberts, Alcatel