Minutes of the S2 meeting #14 4th to 8th of September 2000 Bristol, uk

3.1Geran issues

S2-001609 from G00-0374: LS on inter-BSC hard handover in GERAN for the packet switched domain

GERAN are asking 4 specific questions to SA2. They also summarise their main working assumptions, among which: the Iur-g interface supports a sub-set of the RNSAP protocol as defined for UTRAN, and the Iur-g interface does not contain a user plane.

Discussion: Alcatel is challenging this last assumption in S2-001397.

Conclusion: See conclusions of S2-001397.
S2-001397 from Alcatel: Use of Iur and Iu-ps interfaces – Handovers (on , R00)

Alcatel propose here: to use the Iur for signalling between two GERAN-BSCs, to use this Iur to transfer the MAC-PDUs between two GERAN BSCs as to hide inter-BSC hard handover to the CN (there will then be a “Serving BSC” and a “Drift BSC” as in UTRAN), to use the same mechanisms for hard handovers and relocations in GERAN as in UMTS and finally to use the Iur for signalling only between a GERAN-BSC and a UTRAN RNC.

Tdoc S2-001398 provides the actual changes to 23.121.

Discussion: The LS in GERAN is showing that GERAN has taken different assumption, in particular on the use of the Iur. Alcatel propose to reply to GERAN that their solution has also to be considered, for the reasons presented in this tdoc (QoS during HO, load balancing,…).

The case of a Class A mobile is not mentioned in Alcatel’s contribution: the speech might be also transported over the Iur, but this needs further study.

Alcatel have no information if a similar contribution was presented to GERAN last week, but, if it was presented, then it seems according to the LS that it was rejected.

Conclusion: Proposed answer to S2-001609 in S2-001613. To be decided later on, based on its content, whether it has to be sent or not.

For the other questions of S2-001609, a drafting group is established.

S2-001613 from Alcatel: Draft LS to GERAN (Cc R2, R3) on inter-BSC hard handover in GERAN for the packet switched domain

Proposed answer to S2-001397.

It is mentioned that S2 has some concerns about the GERAN’s assumption that Iur-g interface does not contain a user plane.

The other questions are answered as much as possible.

Discussion: Some actions are expected from R3, so they should be in the “to” field and not as Cc.

“the independence of CN for Hard HO…” is removed and it should be clarified that hard Hos are still needed.

Conclusion: Editorially revised to S2-001637.
S2-001637 from SA2: LS to GERAN and R3 (Cc R2) on inter-BSC hard handover in GERAN for the packet switched domain

Editorial revision of S2-001613