ETSI STC SMG2	Tdoc SMG2  515/99
Meeting no 30	Agenda item 8.2.3
Dublin, Ireland
12 - 16 April 1999

Source 	SMG2
To:		SMG3 WPA
		SMG1, SMG12

Proposed  Liaison Statement on Serviced Based Cell Selection.

SMG2 has considered the Liaison Statement from SMG3 WPA entitled ’Service Based Cell Selection’. 

SMG2 confirms that Service Based Cell selection is not supported by GSM. This rules out the use of such a feature by GPRS mobiles. This has been concluded several times in SMG2. 

SMG2 also notes that the information broadcast in one cell only gives information of if that cell supports GPRS or not, but does not tell anything about the rest of the network. It is therefore not possible to select a suitable PLMN based on this information except for the case where the MS is stationary. 

Two modes for PLMN selection are mandatory, manual and automatic. In addition the MS manufacturer is allowed to implement other options so that the user can define his own lists of preferred PLMNs according to information of coverage for the required service available from the operator. It could also be possible to update these lists by the specified SIM toolkit.

SMG2 believes that the use of such methods is a better way to achieve the wanted goal then to base the PLMN selection on BCCH information read on one cell.

However, SMG2 does not anticipate any problems for the radio interface with the proposed method since the PLMN selection is not in any case based on optimisation of the interference situation. 

Concerning the already introduced change to 03.22, which allows the mobile station to delay the PLMN selection when coverage is lost, SMG2 has the following comment. It is not appropriate that any GPRS MS, which is defined as an MS capable of GPRS service, shall use this delay. Only in case the MS is attached to GPRS, the option may be used. Therefore the following change is proposed:

EXCEPTION: If registration is not possible on recovery from lack of coverage due to the registered PLMN being unavailable, a MS attached to GPRS services may, optionally, continue looking for the registered PLMN for an implementation dependent time.