1 Scope

3GPP44.160General Packet Radio Service (GPRS)Mobile Station (MS) - Base Station System (BSS) interfaceRadio Link Control / Medium Access Control (RLC/MAC) protocol Iu modeRelease 16TS

1.1 General

The present document specifies procedures for the following layers of the radio interface (Um reference point), the interface between the GSM/EDGE Radio Access Network (GERAN) and the Mobile Station (MS) in GERAN Iu mode:

– Radio Link Control (RLC).

– Medium Access Control (MAC), including Physical Link Control functions.

1.2 Related documents

The following documents provide information related to the present document:

– 3GPP TS 43.051 is an overall description of the GSM/EDGE Radio Access Network (GERAN) in Iu mode.

– 3GPP TS 44.003 specifies channel types, access capabilities and channel configurations at the Um reference point.

– 3GPP TS 44.004 specifies services offered by the physical layer of the Um reference point. It also specifies control channels. RLC and MAC use these services and control channels.

– 3GPP TS 24.007 specifies, in general terms, this protocol’s structured functions, its procedures and its relationship with other layers and entities. It also specifies the basic message format and error handling applied by layer 3 protocols.

– 3GPP TS 44.118 specifies the RRC procedures when operating in Iu mode.

– 3GPP TS 44.060 specifies RLC/MAC procedures specific to A/Gb mode as well as the procedures that are common to both A/Gb mode and Iu mode. It also specifies the messages and Information Elements for both modes.

– 3GPP TS 51.010 specifies test procedures for radio-interface signalling.

1.3 Use of logical control channels

3GPP TS 45.002 defines the following logical control channels:

– Broadcast Control Channel (BCCH): downlink only, used to broadcast Cell specific information.

– Packet Broadcast Control Channel (PBCCH): downlink only, used to broadcast Cell specific information.

– Packet Paging Channel (PPCH): downlink only, used to send page requests to Mobile Stations (MSs).

– Packet Random Access Channel (PRACH): uplink only, used to request GPRS resources.

– Packet Access Grant Channel (PAGCH): downlink only, used to allocate GPRS resources.

– Packet Associated Control Channel (PACCH): bi-directional, associated with a Temporary Block Flow (TBF).

– Packet Timing advance control channel uplink (PTCCH/U): used to transmit random access bursts to allow estimation of the timing advance for one MS in transfer state.

– Packet Timing advance control channel downlink (PTCCH/D): used to transmit timing advance updates for several MS. One PTCCH/D is paired with several PTCCH/U’s.

1.4 Use of logical traffic channels

3GPP TS 45.002 defines the following logical traffic channels used by RLC and MAC:

– Traffic Channel (TCH): bidirectional, carries encoded speech or user data using GMSK on a dedicated basic physical subchannel (DBPSCH). TCH can be full-rate (TCH/F) or half-rate (TCH/H).

– Octal Traffic Channel (O-TCH): bidirectional, carries encoded speech using 8-PSK on a DBPSCH. O-TCH can be full-rate (O‑TCH/F) or half-rate (O-TCH/H).

– Enhanced Traffic Channel (E-TCH): bidirectional, carries user data using 8-PSK on a DBPSCH.

– Packet Data Traffic Channel (PDTCH): downlink or uplink, carries user data using GMSK or 8-PSK on a shared basic physical subchannel (SBPSCH) or a DBPSCH. PDTCHs can be full-rate (PDTCH/F) or half-rate (PDTCH/H).

1.4a Use of transport channels

For the flexible layer one (FLO) 3GPP TS 45.002 defines the following transport channel type:

– Dedicated Channel (DCH): carries user or control data using GMSK or 8-PSK on a DBPSCH. A mobile station may have one or more transport channels of type DCH active at the same time in each direction.

In the present document, the following notations are used:

– UDCH: refers to a transport channel of type DCH used exclusively for carrying RLC/MAC blocks for data transfer belonging to user-plane;

– CDCH: refers to a transport channel of type DCH used exclusively for carrying RLC/MAC blocks for data transfer belonging to control-plane. The signalling TFC (see 3GPP TS 44.118) shall be used when CDCH is active;

– ADCH: refers to a transport channel of type DCH used exclusively for carrying RLC/MAC blocks for control message transfer. The signalling TFC (see 3GPP TS 44.118) shall be used when ADCH is active.

1.5 Conventions

Unless explicitly stated otherwise, the following conventions apply:

– The notations "further study", "FS" or "FFS" indicate the annotated text is not normative.

– References to "PDCH" also apply to "SBPSCH" and vice-versa.