7 Requirements for Handover from GERAN to UTRAN

22.1293GPPHandover requirements between UTRAN and GERAN or other radio systemsRelease 17Service aspectsTS

7.1 Operational Requirements

7.1.2 GERAN bands

The standard shall support handover from any combination of GERAN bands supported by the GERAN specifications.

7.2 Performance Requirements

During handover from GERAN to UTRAN, temporary degradations shall be no greater than for intra-GERAN handovers.

7.3 Specific Requirements for Individual Service Handover from GERAN to UTRAN

7.3.1 Speech

AMR, EFR, FR and HR calls shall be mapped to the default UTRAN speech codec.

7.3.2 Short Message Service

There are no requirements related to handover for short message service.

7.3.3 Cell Broadcast

There are no requirements related to handover for cell broadcast.

7.3.4 USSD

The technical specifications shall provide means to ensure that any handover that occurs during a USSD interaction need no more affect the service than intra-GERAN handover.

7.3.5 Facsimile

It is not required that a facsimile transmission that is active between UE and network at the time of handover from GERAN to UTRAN completes successfully.

7.3.6 Data Bearer Services

7.3.6.1 Circuit Switched Data

Specifications shall be defined to permit the possibility of handover of a data bearer from GERAN to UTRAN.

Means shall be defined which make it possible to limit any temporary degradation on handover so it meets the performance specified by GERAN service requirements for circuit switched data handover.

7.3.6.2 Packet Switched Data

It is required to handover a user context between GERAN and UTRAN. Independently of the used radio interface, the user shall stay connected to an external network (internet, intranet). Any change in the QoS shall be seen at the service access points as a network initiated renegotiation of QoS. If the supported QoS is not acceptable, the UE/user may terminate the connection/context.

Means shall be defined which make it possible to limit any temporary degradation on handover so it meets the performance specified by GERAN service requirements for packet switched data handover.

7.3.7 Supplementary services

Control and use of Supplementary Services should not be effected by a handover to UTRAN.

7.4 Requirements on multiple bearer services handover from GERAN to UTRAN

Consideration must be given to services that may involve the use of multiple bearer services. For example Class A GPRS terminals will be capable of simultaneously supporting more than one data bearer services. Means shall be defined to allow handover of several data bearer services from GERAN to UTRAN