Transmission of the fixed size PDUs through the transparent RLC

Apparatus for use in establishing a radio bearer (RB) relating to a request from a core network (CN) to a radio access network (RAN) in a mobile telecommunications system (UMTS), comprising:

• means for determining (220) that a requested mode for an interface between said CN and said RAN is a transparent mode and for signaling (223) a segmentation state indicator to a segmentation/reassembly layer of said RAN;
• and
• means (234) responsive to said segmentation state indicator, for blocking segmentation in said segmentation/reassembly layer of said RAN for said RB in case said indicator indicates an inactive segmentation state and for permitting (108) segmentation in said segmentation/reassembly layer of said RAN in case said indicator indicates an active segmentation state.

Apparatus for handling fixed-size service data units (SDUs) in a downlink from a core network of a mobile telecommunications system by a radio access network (RAN) of said system, comprising:

• means (234) for storing plural SDUs at a segmentation/reassembly layer in said RAN, each SDU provided in a minimum interleaving period in a transparent mode for retrieving said stored plural SDUs and for providing said retrieved plural SDUs in one or more protocol data units (PDUs) in one or more data transport blocks;
• and
• means (238) for providing said one or more data transport blocks with a transport format indicator (TFI) for transmission over a radio interface from said RAN to a user equipment (UE) in a transmission time interval (TTI) having a duration greater than said minimum interleaving period.

Apparatus for handling fixed-size service data units (SDUs) in an uplink from a user equipment (UE) of a mobile telecommunications system via a radio interface (320) to a radio access network (RAN) and from the RAN via an interface (333) to a core network (CN) of said system, comprising:

• means (280) for storing plural SDUs at a segmentation/reassembly layer in said UE, each SDU provided in a minimum interleaving period in a transparent mode for retrieving said stored plural SDUs and providing said retrieved plural SDUs in one or more protocol data units (PDUs) in one or more transport blocks;
• and
• means (310) for providing said one or more transport blocks with a transport format indicator (TFI) for transmission over said radio interface from said UE to said RAN in a transmission time interval (TTI) having a duration greater than said minimum interleaving period.