7 Medium Access Control (MAC) procedures on PCCCH

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

Tools: ARFCN - Frequency Conversion for 5G NR/LTE/UMTS/GSM

7.1 General

The establishment of a Temporary Block Flow (TBF) can be initiated by either the mobile station or the network.

The request for establishment of a TBF using the PCCCH is described in this sub-clause. For mobile stations in MAC-Idle state measurement reports messages are sent on temporary fixed allocations without the establishment of an uplink TBF (see sub-clause 7.4).

7.2 TBF establishment initiated by the mobile station on PCCCH

7.2.1 General

The purpose of the packet access procedure is to establish a TBF to support the transfer of upper-layer PDUs in the direction from the mobile station to the network. Packet access shall be done on PCCCH, as defined in this sub-clause. The packet access can be done in either one phase (sub-clause 7.2.3) or in two phases (sub-clauses 7.2.3 and 7.2.4).

TBF establishment can also be done on PACCH if a TBF for transfer of upper-layer PDUs in the direction from the network to the mobile station is already established (see sub-clause 8.2.2.1.3). TBF establishment can also be done on PACCH if the mobile station is releasing its last TBF for transfer of upper-layer PDUs in the direction from the mobile station to the network and TBF for transfer of upper-layer PDUs in the direction from the network to the mobile station is not established (see sub-clause 10.4.5.5 and sub-clause 10.4.6.4).

If the mobile station is in MAC-Dedicated state the establishment of a TBF shall be performed by the procedures specified in 3GPP TS 44.118.

The packet access procedure is initiated by the mobile station. Initiation is triggered by a request from upper layers to transfer an upper-layer PDU using the primitives that are defined in sub-clause 4.3.

Upon such a request:

– if access to the network is allowed (sub-clause 7.2.2), the mobile station shall initiate the packet access procedure as defined in sub-clause 7.2.3.1.1;

– otherwise, the MAC sublayer in the mobile station shall reject the request.

7.2.2 Permission to access the network

See 3GPP TS 44.060 sub-clause 7.1.1.

7.2.3 Initiation of a TBF establishment

7.2.3.1 Initiation of the packet access procedure

7.2.3.1.1 General

The mobile station shall initiate the packet access procedure by scheduling the sending of (EGPRS) PACKET CHANNEL REQUEST messages on the PRACH corresponding to its PCCCH_GROUP. The mobile station shall use the last access parameters received on PBCCH. At sending of the first (EGPRS) PACKET CHANNEL REQUEST message, the mobile station shall store the value for the Retry (R) bit to be transmitted in all the subsequent MAC headers for this TBF as ‘MS sent channel request message once’. If a second (EGPRS) PACKET CHANNEL REQUEST message is sent, the mobile station shall change the value for the Retry (R) bit to ‘MS sent channel request message once or more’.

While waiting for a response to the (EGPRS) PACKET CHANNEL REQUEST message, the mobile station shall monitor the full PCCCH corresponding to its PCCCH_GROUP. The mobile station shall perform signal strength measurements as they are defined for MAC-Idle state (see 3GPP TS 45.008).

While monitoring the full PCCCH, the mobile station shall decode any occurrence of the PERSISTENCE_LEVEL parameter included in a message received on PCCCH. When the mobile station receives the PERSISTENCE_LEVEL parameter, the value of the PERSISTENCE_LEVEL parameter shall be taken into account at the next (EGPRS) PACKET CHANNEL REQUEST attempt that follows.

The (EGPRS) PACKET CHANNEL REQUEST messages are sent on PRACH and contain an indication of the type of access and parameters required to indicate the mobile station’s demand of radio resource.

There are two formats of the PACKET CHANNEL REQUEST message containing either 8 bits or 11 bits of information. The format to be applied on PRACH is controlled by the parameter ACC_BURST_TYPE which is broadcast on PBCCH. The cause value to be used in the PACKET CHANNEL REQUEST message for a non-EGPRS TBF mode capable MS depends on the purpose of the packet access procedure as follows:

– If the mobile station intends to use the TBF to send user data it shall determine the RLC mode from the configuration of the radio bearer for which the TBF is to be established. If the requested RLC mode is acknowledged mode, the mobile station shall request either one phase access or two phase access. If the requested RLC mode is unacknowledged mode, the mobile station shall indicate in the PACKET CHANNEL REQUEST message either One phase Access Request in RLC unacknowledged mode or two phase access.

– If the purpose of the packet access procedure is to send a message on SRB1; in this case, the mobile station shall indicate either ‘Single Block Without TBF Establishment’ or ‘One phase Access Request in RLC unacknowledged mode’ in the PACKET CHANNEL REQUEST message.

– If the purpose of the packet access procedure is to send a message on SRB2-4 and a dedicated channel is not needed; in this case the mobile station shall indicate ‘MM Procedure’ in the PACKET CHANNEL REQUEST message.

– If the purpose of the packet access procedure is to send a message on SRB2-4 and a dedicated channel is needed; in this case, the mobile station shall indicate ‘Dedicated channel request’ in the PACKET CHANNEL REQUEST message

– If the purpose of the packet access procedure is to initiate an Emergency Call; in this case, the mobile station shall indicate ‘Emergency Call’ in the PACKET CHANNEL REQUEST message.

– If the purpose of the packet access procedure is to request multiple TBFs, the mobile station shall request a two phase access.

EGPRS TBF mode capable MSs shall monitor the GPRS Cell Options IE on the PBCCH(PSI1/PSI13) for the cell’s EGPRS capability. In the GPRS Cell Options IE it is also indicated if the EGPRS PACKET CHANNEL REQUEST is supported in the cell.

– If the cell is EGPRS TBF mode capable and EGPRS PACKET CHANNEL REQUEST is supported in the cell the EGPRS PACKET CHANNEL REQUEST messages shall be used at one-phase access attempts (in RLC acknowledged or unacknowledged mode), two-phase access attempts, sending of a message on SRB2-4 if a dedicated channel is needed or initiation of an emergency call. The corresponding cause value shall be used.

– If the cell is EGPRS TBF mode capable and EGPRS PACKET CHANNEL REQUEST messages are not supported in the cell or if the cell is not EGPRS TBF mode capable, the EGPRS TBF mode capable mobile station shall use the PACKET CHANNEL REQUEST message as for non-EGPRS TBF mode capable MSs (see above).

7.2.3.1.2 Access persistence control on PRACH

See 3GPP TS 44.060 sub-clause 7.1.2.1.1.

7.2.3.2 Packet assignment procedure

7.2.3.2.1 On receipt of a PACKET CHANNEL REQUEST or EGPRS PACKET CHANNEL REQUEST message

7.2.3.2.1.1 General

On receipt of a PACKET CHANNEL REQUEST or EGPRS PACKET CHANNEL REQUEST message, the network may assign to the mobile station a radio resource on either one or more SBPSCHs or on one or more DBPSCHs, based on the cause field in the received message. The network shall not assign more than one DBPSCH/S to the mobile station.

7.2.3.2.1.2 Allocation of resource on SBPSCH(s)

See 3GPP TS 44.060 sub-clause 7.1.2.2.1

7.2.3.2.1.3 Allocation of resource on DBPSCH(s)

When the mobile station has been allocated a resource on one or more DBPSCHs, the allocated dedicated resource is assigned to the mobile station in a PACKET DBPSCH ASSIGNMENT message, sent on any PAGCH block on the same PCCCH on which the network has received the PACKET CHANNEL REQUEST or EGPRS PACKET CHANNEL REQUEST message. The Packet Request Reference information element shall be used to address the mobile station and frequency parameters shall be included.

The mobile station may use information received on PBCCH or a previous assignment message to decode the frequency parameters contained in the assignment message. If the mobile station detects an invalid Frequency Parameters information element in the assignment message, it shall abort the procedure, if required initiate a partial acquisition of PBCCH information, and may then re-initiate this procedure.

In case the allocated channel type is PDTCH+PACCH+SACCH (see 3GPP TS 44.060), the network shall include the USF value to be used on PDTCH and PACCH in the PACKET DBPSCH ASSIGNMENT message.

On receipt of a PACKET DBPSCH ASSIGNMENT message corresponding to one of its 3 last PACKET CHANNEL REQUEST or EGPRS PACKET CHANNEL REQUEST messages the mobile station shall stop timers T3186 and T3170 if running and stop sending PACKET CHANNEL REQUEST or EGPRS PACKET CHANNEL REQUEST messages. The mobile station shall then switch to the assigned DBPSCH(s), enter the MAC-Dedicated state and proceed with contention resolution of the one phase packet access procedure according to sub-clause 7.2.3.3.2.

When the mobile station switches to the assigned DBPSCH(s), it shall take into account the power control parameters received in downlink SACCH blocks, perform signal strength measurements and apply output power control procedures as they are defined for MAC-Dedicated state (see 3GPP TS 45.008). The mobile station shall not send any measurement reports until contention resolution is complete. It shall follow the procedures in sub-clauses 9 and 11.

7.2.3.2.1.4 Packet access queuing notification procedure

See 3GPP TS 44.060 sub-clause 7.1.2.2.2.

7.2.3.2.1.5 Packet polling procedure

See 3GPP TS 44.060 sub-clause 7.1.2.2.3.

7.2.3.2.1.6 Packet access reject procedure

The network may, as response to a PACKET CHANNEL REQUEST or EGPRS PACKET CHANNEL REQUEST message, send to the mobile station a PACKET ACCESS REJECT message on any PAGCH block on the same PCCCH on which the channel-request message was received. This message contains the request reference with time of reception of the PACKET CHANNEL REQUEST or EGPRS PACKET CHANNEL REQUEST message and optionally a WAIT_INDICATION field in the Reject structure of the PACKET ACCESS REJECT message.

On receipt of a PACKET ACCESS REJECT message containing a Reject structure addressed to the mobile station, where the Packet Request Reference in the Reject structure corresponds to one of the mobile station’s last 3 PACKET CHANNEL REQUEST or EGPRS PACKET CHANNEL REQUEST messages:

– The mobile station shall stop T3186, stop sending PACKET CHANNEL REQUEST or EGPRS PACKET CHANNEL REQUEST messages, start T3172 with the value indicated in the WAIT_INDICATION field, start T3170 if it has not already been started, and listen to the downlink PCCCH until T3170 expires. During this time, the mobile station shall ignore additional PACKET ACCESS REJECT messages, but on reception of any PACKET UPLINK ASSIGNMENT or PACKET DBPSCH ASSIGNMENT message corresponding to any other of its last 3 PACKET CHANNEL REQUEST or EGPRS PACKET CHANNEL REQUEST messages, the mobile station shall stop T3170, stop T3172, and follow the procedure defined in sub-clause 7.2.3.2.1.

– If no PACKET UPLINK ASSIGNMENT or PACKET DBPSCH ASSIGNMENT message is received before expiration of T3170, the mobile station shall indicate a packet access failure to upper layer and return to MAC-Idle state. As an option, the mobile station may stop T3170, indicate a packet access failure to upper layer and return to MAC-Idle state as soon as it has received responses from the network on all, or in case more than 3 were sent, the last 3 of its PACKET CHANNEL REQUEST or EGPRS PACKET CHANNEL REQUEST messages.

– If an erroneous PACKET UPLINK ASSIGNMENT or PACKET DBPSCH ASSIGNMENT message (e.g., the mobile station has been assigned more PDCHs than it supports according to its multislot class) addressed to the mobile station is received before expiration of T3170, the mobile station shall stop T3170 and act as stated in sub-clause 7.2.5.

– If the mobile station receives a PACKET DOWNLINK ASSIGNMENT message, it shall stop T3170 and respond to the message (see sub-clause 7.3.2).

– If the mobile station receives a PACKET DBPSCH ASSIGNMENT message, it shall stop T3170 and respond to the message (see sub-clause 7.3.3).

– The mobile station shall not make a new attempt for packet access in the same cell until T3172 expires, but may attempt packet access in another cell after successful cell reselection for radio-conditions reasons (see 3GPP TS 45.008).

– The value of the WAIT_INDICATION field (i.e., T3172) relates to the cell from which it was received.

7.2.3.3 Contention resolution at one phase access

7.2.3.3.1 Contention resolution at one phase access on SBPSCHs

The G-RNTI is used to uniquely identify the mobile station when sending on uplink. The Radio bearer Id is used to identify the RLC instance to which the RLC/MAC block belongs. Every RLC data block that is sent on the TBF shall include the G-RNTI of the mobile station and the RB Id of the RLC instance being addressed, until the contention resolution is completed on the mobile station side. If MCS-7, MCS-8 or MCS-9 is used for the transmission of the G‑RNTI and RB Id in EGPRS TBF mode (i.e. the RLC/MAC block is carrying two RLC data blocks), the G-RNTI and RB Id shall be inserted in both RLC data blocks. The G-RNTI and RB Id shall also be included in the PACKET RESOURCE REQUEST message, if sent during the contention resolution. If ciphering is used, the least significant bit of the uplink HFN of this radio bearer shall be inserted in each RLC data block sent on the TBF and if applicable in the PACKET RESOURCE REQUEST message until the contention resolution is completed on the mobile station side. If the least significant bit of the HFN in the network for the same radio bearer in the same direction is different from the one received from the mobile station, the network shall increase its HFN by one unit.

The retransmission of an RLC data block shall include the G-RNTI and RB Id if the RLC data block was originally transmitted including these fields, also if the retransmission occurs after the completion of the contention resolution.

At sending of the first RLC data block, the mobile station shall stop timer T3164, set counter N3104 to 1, and start timer T3166. The counter N3104 shall be stepped each time the mobile station sends an RLC data block.

The network shall respond by including the G-RNTI in the PACKET UPLINK ACK/NACK message after the first correctly received RLC data block that comprises the G-RNTI and RB Id. In EGPRS TBF mode, the network may instead respond by addressing the mobile station with the TFI of the assigned TBF and including the G-RNTI (in the CONTENTION_RESOLUTION_TLLI field) in a PACKET UPLINK ASSIGNMENT message, if the resources allocated for the TBF need to be reallocated (see sub-clause 8.2.2.1.2).

The contention resolution is completed on the network side when the network receives an RLC data block that comprises the G-RNTI value that identifies the mobile station, the RB Id that identifies the RLC instance being addressed and the TFI value associated with the TBF.

The contention resolution is successfully completed on the mobile station side when the mobile station receives a PACKET UPLINK ACK/NACK message addressing the mobile station with the TFI value associated with the uplink TBF and including the same G-RNTI value that the mobile station has included in the RLC header of the first RLC data blocks, or alternatively, in EGPRS TBF mode, a PACKET UPLINK ASSIGNMENT message addressing the mobile station with the TFI value associated with the uplink TBF and including the same G-RNTI value that the mobile station included in the RLC header of the first RLC data blocks. The mobile shall then stop timer T3166 and counter N3104.

The contention resolution has failed on the mobile station side when the counter N3104 reaches its maximum value, or timer T3166 expires. The contention resolution also fails, if the mobile station receives a PACKET UPLINK ACK/NACK message or in EGPRS TBF mode alternatively a PACKET UPLINK ASSIGNMENT message addressing the mobile station with the TFI associated with the uplink TBF and including a G-RNTI value other than that the mobile station included in the RLC header of the first RLC data blocks; in such a case, the mobile station shall not transmit a PACKET CONTROL ACKNOWLEDGEMENT in the uplink radio block specified if a valid RRBP field is received as part of the PACKET UPLINK ACK/NACK message or in EGPRS TBF mode alternatively as part of the PACKET UPLINK ASSIGNMENT message.

In case of a contention resolution failure on the mobile station side, the mobile station shall reset the counter N3104 and stop timer T3166. The mobile station shall stop transmitting on the TBF and reinitiate the packet access procedure, unless the packet access procedure has already been attempted four times. In that case, a TBF failure has occurred, see sub-clause 7.2.5.

7.2.3.3.2 Contention resolution at one phase access on DBPSCH

7.2.3.3.2.1 General

During contention resolution the mobile station shall only send on the RB for which packet access was initiated via the PCCCH. The RB may be mapped onto a PDTCH, SDCCH or FACCH logical channel.

7.2.3.3.2.2 Contention resolution at one phase access on PDTCH

The G-RNTI is used to identify uniquely the mobile station when sending on uplink. The Radio bearer Id is used to identify the RLC instance to which the RLC/MAC block belongs. Every RLC data block that is sent on any of the mobile station’s TBFs, shall include the G-RNTI of the mobile station, until the contention resolution is completed on the mobile station side.

The retransmission of an RLC data block shall include the G-RNTI if the RLC data block was originally transmitted including this field, also if the retransmission occurs after the completion of the contention resolution.

At sending of the first RLC data block, the mobile station shall set counter N3104 to 1, and start timer T3166. The counter N3104 shall be incremented each time the mobile station sends a RLC data block.

The network shall respond by including the G-RNTI in the PACKET UPLINK ACK/NACK message after the first correctly received RLC data block that comprises the G-RNTI and valid RB Id.

The contention resolution is completed on the network side when the network receives an RLC data block that comprises the G-RNTI value that identifies the mobile station, and a valid RB Id that identifies the RLC instance to which the RLC/MAC block belongs.

The contention resolution has failed on the mobile station side when the counter N3104 reaches its maximum value, or timer T3166 expires. The contention resolution also fails, if the mobile station receives a PACKET UPLINK ACK/NACK message addressing the mobile station with a G-RNTI value other than that the mobile station included in the RLC header of the first RLC data blocks; in such a case, the mobile station shall not transmit a PACKET CONTROL ACKNOWLEDGEMENT in the uplink radio block specified if a valid RRBP field is received as part of the PACKET UPLINK ACK/NACK message.

7.2.3.3.2.3 Contention resolution at one phase access on SDCCH or FACCH

The G-RNTI is used to identify uniquely the mobile station when sending on uplink. The Reduced Radio bearer Id is used to identify the RLC instance to which the RLC/MAC block belongs. Every RLC data block that is sent on any of the mobile station’s TBFs, shall include the G-RNTI of the mobile station, until the contention resolution is completed on the mobile station side.

The network shall respond by including the G-RNTI in the PACKET DBPSCH UPLINK ACK/NACK message after the first correctly received RLC data block that comprises the G-RNTI and valid RRB Id.

The contention resolution is completed on the network side when the network receives an RLC data block that comprises the G-RNTI value that identifies the mobile station, and a valid RRB Id that identifies the RLC instance to which the RLC/MAC block belongs.

The contention resolution is successfully completed on the mobile station side when the mobile station receives a PACKET DBPSCH UPLINK ACK/NACK message addressing the mobile station with a valid RBId (i.e. associated with an assigned RRB Id) and including the same G-RNTI value that the mobile station included in the RLC header of the first RLC data blocks. The mobile station shall then stop timer T3166 and counter N3104.

The contention resolution has failed on the mobile station side when the counter N3104 reaches its maximum value, or timer T3166 expires. The contention resolution also fails, if the mobile station receives a PACKET DBPSCH UPLINK ACK/NACK message addressing the mobile station with a G-RNTI value other than that the mobile station included in the RLC header of the first RLC data blocks; in such a case, the mobile station shall not transmit a PACKET CONTROL ACKNOWLEDGEMENT even if the poll bit is set in the received message.

7.2.3.4 RLC/MAC procedures during contention resolution

7.2.3.4.1 RLC/MAC procedures during contention resolution on SBPSCHs

During the contention resolution, the mobile station may receive a non-distribution RLC/MAC control message addressing the mobile station by G-RNTI or the TFI value associated with the uplink TBF. The mobile station shall act on that message using the procedure defined for the message when it is received in MAC-Shared state during operation on an uplink TBF (see sub-clause 8), with the following restrictions:

– The mobile station shall not accept a PACKET MEASUREMENT ORDER message, a PACKET CELL CHANGE ORDER message and a PACKET POWER CONTROL/TIMING ADVANCE message addressing the mobile station with the TFI value associated with the uplink TBF.

– The mobile station shall not accept a PACKET DOWNLINK ASSIGNMENT, a MULTIPLE TBF DOWNLINK ASSIGNMENT, a PACKET TIMESLOT RECONFIGURE or a MULTIPLE TBF TIMESLOT RECONFIGURE message.

If a valid RRBP field is received as part of the RLC/MAC control block and the mobile station acts on the message, then it shall transmit a PACKET CONTROL ACKNOWLEDGEMENT message in the uplink radio block specified (see 3GPP TS 44.060 sub-clause 10.4.5); The mobile station shall not transmit a PACKET CONTROL ACKNOWLEDGEMENT message if it does not act on the received message.

In either case, the mobile station shall continue with the contention resolution on the uplink TBF, till it either completes successfully or fails, or that the uplink TBF is released as a result of the procedure defined for the message that is received.

During the contention resolution at one phase access, the mobile station shall not send a Packet Resource Request message to request the establishment of additional UL TBFs.

7.2.3.4.2 RLC/MAC procedures during contention resolution on DBPSCHs

During the contention resolution, the mobile station may receive a non-distribution RLC/MAC control message addressing the mobile station by G-RNTI, RB Id (PACCH) or the RRB Id (SDCCH or FACCH) value associated with one its uplink TBFs. The mobile station shall act on that message using the procedure defined for the message in sub-clause 9.

If a RLC/MAC control block is received with the poll bitset or with valid RRBP field and the mobile station acts on the message, then it shall transmit a PACKET CONTROL ACKNOWLEDGEMENT message in the next possible uplink occurrence on the same logical channel. The mobile station shall continue with the contention resolution on the uplink TBF, until it either completes successfully or fails, or that the uplink TBF is released through release of the dedicated resource using the CRLC-CONFIG primitive (see sub-clause 4.3.3.1)

7.2.3.5 One phase packet access completion

7.2.3.5.1 One phase packet access completion on SBPSCHs

See 3GPP TS 44.060 sub-clause 7.1.2.4.

7.2.3.5.2 One phase packet access completion on DBPSCHs

The one phase packet access procedure is completed upon a successful contention resolution.

7.2.3.6 Timing Advance

7.2.3.6.1 Timing advance on SBPSCHs

See 3GPP TS 44.060 sub-clause 7.1.2.5.

7.2.3.6.2 Timing advance on DBPSCHs

Initial timing advance may be provided in the PACKET DBPSCH ASSIGNMENT message in the TIMING_ADVANCE_VALUE field.

7.2.4 TBF establishment using two phase access

7.2.4.1 Initiation of the Packet resource request procedure

In the first phase of a two-phase access, the same procedures as for one-phase access shall be used until the network sends to the mobile station a PACKET UPLINK ASSIGNMENT message including a Single Block Allocation struct or a Multi Block Allocation struct.. The network may only include a Multi Block Allocation struct if it sends the PACKET UPLINK ASSIGNMENT message in response to an EGPRS PACKET CHANNEL REQUEST.

A two-phase access may be initiated:

– by the network, by ordering the mobile station to send a PACKET RESOURCE REQUEST message. The order shall be sent implicitly to the mobile station in the PACKET UPLINK ASSIGNMENT message by including a Single Block Allocation struct or a Multi Block Allocation struct;

– by a mobile station, by requiring a two-phase access in the PACKET CHANNEL REQUEST or EGPRS PACKET CHANNEL REQUEST message. If access is granted, the network shall order the mobile station to send a PACKET RESOURCE REQUEST message. The order shall be sent implicitly to the mobile station in the PACKET UPLINK ASSIGNMENT message by including a Single Block Allocation struct or a Multi Block Allocation struct.

When the mobile station has received the PACKET UPLINK ASSIGNMENT message, it shall respond with a PACKET RESOURCE REQUEST message in the first allocated radio block. If the network allocated more than a single radio block, the mobile station shall send any of the following in each additional block:

– Another control block (e.g., a PACKET UPLINK DUMMY CONTROL BLOCK or a PACKET MEASUREMENT REPORT message); however, the mobile station shall not send an ADDITIONAL MS RADIO ACCESS CAPABILITIES message or a PACKET RESOURCE REQUEST message.

– Nothing.

The mobile station may request the establishment of multiple UL TBFs in the PACKET RESOURCE REQUEST message. The MS Radio Access Capability IE shall not be included in the PACKET RESOURCE REQUEST message. If ciphering is used, the least significant bit of the uplink HFN of the radio bearer for which radio resources are requested, shall be inserted in the PACKET RESOURCE REQUEST message. If the least significant bit of the HFN in the network for the same radio bearer in the same direction is different from the one received from the mobile station, the network shall increase its HFN by one unit.

When the mobile station switches to the assigned PDCH, it shall take the power control parameters received in the PACKET UPLINK ASSIGNMENT message into account, perform signal strength measurements and apply output power control procedures as they are defined for MAC-Shared state (see 3GPP TS 45.008).

At sending of the PACKET RESOURCE REQUEST message, the mobile station shall start timer T3168 for each of the radio bearers for which resources were requested. Furthermore, the mobile station shall not respond to PACKET DOWNLINK ASSIGNMENT or MULTIPLE TBF DOWNLINK ASSIGNMENT messages – but may acknowledge such messages if they contain a valid RRBP field – while timer T3168 is running, before contention resolution is completed on the mobile station side.

The mobile station may indicate in the PACKET RESOURCE REQUEST message the number of octets of user data it has to transfer.

7.2.4.2 Packet resource assignment for uplink procedure

7.2.4.2.1 (void)

7.2.4.2.2 On receipt of a PACKET RESOURCE REQUEST message

On receipt of a PACKET RESOURCE REQUEST message, the network shall respond by sending a PACKET UPLINK ASSIGNMENT or MULTIPLE TBF UPLINK ASSIGNMENT message (radio resources assignment on one or more PDCHs to be used by the mobile station for the TBF in EGPRS or GPRS TBF mode) or a PACKET ACCESS REJECT message to the mobile station on PACCH on the same PDCH on which the mobile station has sent the PACKET RESOURCE REQUEST message. These messages may only be for a subset of the resources requested in the PACKET RESOURCE REQUEST message. For the resource requests that have not been processed by the first assignment or reject message, additional PACKET UPLINK ASSIGNMENT, MULTIPLE TBF UPLINK ASSIGNMENT or PACKET ACCESS REJECT messages may be sent to the mobile station on the PACCH to which the mobile station has been assigned.

On receipt of a PACKET UPLINK ASSIGNMENT or MULTIPLE TBF UPLINK ASSIGNMENT message the mobile station shall switch to the assigned PDCHs. If dynamic or extended dynamic allocation is assigned then start timer T3164 for each of the TBFs that have been assigned resources.

At sending of the first RLC data block on a TBF, the mobile station shall stop timer T3164 for that TBF.

The mobile station may use information received on PBCCH or a previous assignment message to decode the frequency parameters contained in the assignment message. If the mobile station detects an invalid Frequency Parameters information element in the assignment message, it shall abort the procedure, if required initiate a partial acquisition of PBCCH information, and may then re-initiate the access on the PRACH.

On receipt of a PACKET ACCESS REJECT message that contains a Reject structure addressed to the mobile station, the mobile station shall stop timer T3168 and indicate a packet access failure to upper layer for those TBFs identified as rejected in the message.

If the PACKET ACCESS REJECT message contains a WAIT_INDICATION field in a Reject structure addressed to the mobile station, the mobile station shall start timer T3172 with the indicated value (Wait Indication). The mobile station is not allowed to make a new attempt for packet access in the same cell until all instances of timer T3172 expires, but may attempt packet access in another cell after successful cell reselection.

7.2.4.3 Contention resolution at two phase access

The contention resolution is completed on the network side when the network receives a G-RNTI value identifying the mobile station, as part of the contention resolution procedure on the TBF.

The contention resolution is completed on the mobile station side when the mobile station receives a PACKET UPLINK ASSIGNMENT message or MULTIPLE TBF UPLINK ASSIGNMENT message with the same G-RNTI as the mobile station has included in the PACKET RESOURCE REQUEST message and assigning resource to at least one radio bearer that requested resource in the PACKET RESOURCE REQUEST message. The mobile station shall then stop timer T3168 for each radio bearer for which resource is granted. It does not include its G-RNTI in any RLC data block.

The contention resolution has failed on the mobile station side when the mobile station does not receive a PACKET UPLINK ASSIGNMENT message or MULTIPLE TBF UPLINK ASSIGNMENT message with its G-RNTI, assigning resource to at least one radio bearer that requested resource in the PACKET RESOURCE REQUEST message, before expiry of timer T3168. The mobile station shall then reinitiate the packet access procedure unless the packet access procedure has already been attempted four times. In that case, TBF failure has occurred for all of the requested TBF(s) and an RLC/MAC error should be reported to the higher layer for each of the radio bearers that requested resources.

On expiry of an instance of timer T3168 after contention resolution is completed on the mobile station side, TBF establishment for the corresponding radio bearer has failed. In that case the mobile station shall reinitiate resource request for that radio bearer using the procedures described in sub-clause 8.2.2.1.2

7.2.4.4 Two phase packet access completion

See 3GPP TS 44.060 sub-clause 7.1.3.4.

7.2.4.5 Timing Advance

See 3GPP TS 44.060 sub-clause 7.1.3.5.

7.2.5 Abnormal cases

If a failure occurs on the mobile station side of the new TBF before the mobile station has successfully completed contention resolution, the newly reserved resources are released; the subsequent behaviour of the mobile station depends on the type of failure and previous actions.

– If the failure is due to a G-RNTI mismatch, or to the expiry of timers T3166 or T3168, or to the fact that the counter N3104 reaches its maximum value in the contention resolution procedure, and repetition as described in sub-clauses 7.2.3.3, 3GPP TS 44.060 sub-clause 7.1.3.2.1 or sub-clause 7.1.3.3 has been performed, the mobile station shall return to MAC-Idle state, notify higher layer (TBF establishment failure), transactions in progress shall be aborted and cell reselection may take place, unless the failure takes place during a Packet Cell Change Order procedure, in which case the mobile behaviour shall be as described in the Abnormal cases of theNetwork controlled cell reselection procedure in 3GPP TS 44.060 sub-clause 8.4.2.

– If the mobile station has been assigned more PDCHs than it supports according to its MS multislot class, the mobile station shall reinitiate the packet access procedure unless the packet access procedure has already been attempted four times. In that case, TBF failure has occurred.

– If the information in the PACKET UPLINK ASSIGNMENT message does not properly specify an uplink PDCH or violates the mobile station’s multislot capabilities, the mobile station shall reinitiate the packet access procedure unless the packet access procedure has already been attempted four times. In that case, TBF failure has occurred.

– If the mobile station has been assigned more than one DBPSCH/S, the mobile station shall reinitiate the packet access procedure unless the packet access procedure has been attempted four times. In that case, TBF failure has occurred.

– If the information in the PACKET DBPSCH ASSIGNMENT message does not properly specify a DBPSCH or violates the mobile station’s multislot capabilities, the mobile station shall reinitiate the packet access procedure (i.e. using access cause "dedicated channel request") unless the packet access procedure has already been attempted four times. In that case, TBF failure has occurred.

– If the mobile station has been assigned a TCH that it does not support (e.g. using 8-PSK), the mobile station shall return to MAC-Idle state and notify higher layers (TBF establishment failure).

– If the information in the MULTIPLE TBF UPLINK ASSIGNMENT message does not properly specify an uplink PDCH or violates the mobile station’s multislot capabilities, the mobile station shall reinitiate the packet access procedure for each of the TBFs for which there is an error unless the procedure has already been attempted 4 times for the TBF. In that case, TBF failure has occurred.

– If the MULTIPLE TBF UPLINK ASSIGNMENT message contains assignments for radio bearers for which a TBF was not requested, the mobile station shall not act upon these assignments. The mobile station shall act upon the valid assignments.

– If the MULTIPLE TBF UPLINK ASSIGNMENT message contains assignments such that more than one RB is mapped onto one TBF, then TBF failure has occurred for each of the RBs that are mapped onto the same TBF.

– If the mobile station has been assigned a TBF in EGPRS mode and the MS does not support EGPRS, or has been assigned an MCS (e.g. 8-PSK in the Uplink) that the MS does not support, the MS shall return to MAC-Idle state and notify higher layers (TBF establishment failure).

– On expiry of timer T3164, the mobile station shall reinitiate the packet access procedure for the related RB unless the packet access procedure has already been attempted four times for this RB, in which case the mobile station shall notify higher layers of TBF establishment failure. If the mobile station has no remaining TBFs it shall return to MAC-Idle state.

– If the failure is due to any other reason, the mobile station shall return to MAC-Idle state, notify higher layer (TBF establishment failure), transactions in progress shall be aborted and cell reselection continues.

7.3 TBF establishment initiated by the network on PCCCH

7.3.1 General

The purpose of network initiated TBF establishment is to establish a TBF to support the transfer of upper layer PDUs in the direction from the network to the mobile station. The procedure may be entered when the mobile station is in MAC‑Idle state. Network initiated TBF establishment can also be done on PACCH if a TBF for transfer of upper layer PDUs in the direction from the mobile station to the network is already established (sub-clause 8.2.3.5).

If the mobile station is in MAC-Dedicated state the establishment of a TBF shall be performed by procedures that are specified in 3GPP TS 44.118.

7.3.2 Entering the MAC-Shared state

7.3.2.1 General

The procedure is triggered by a request from upper layers on the network side to transfer an upper layer PDU to a mobile station in MAC-Idle state. The request is implicit when receiving an upper layer PDU to a mobile station not already having any assigned radio resources. Upon such a request, the network shall initiate a packet downlink assignment procedure as defined in sub-clause 7.3.2.2.

7.3.2.2 Packet downlink assignment procedure

7.3.2.2.1 Packet downlink assignment procedure

See 3GPP TS 44.060 sub-clause 7.2.1.1.

7.3.2.2.2 HFN synchronization

If ciphering is used, the least significant bit of the downlink HFN of this radio bearer shall be inserted in the PACKET DOWNLINK ASSIGNMENT message sent in the packet downlink assignment procedure (see sub-clause 7.3.2.2.1). If the least significant bit of the HFN in the mobile station for the same radio bearer in the same direction is different from the one received from the network, the mobile station shall increase its HFN by one unit.

7.3.2.3 Packet downlink assignment procedure completion

See 3GPP TS 44.060 sub-clause 7.2.1.2.

7.3.2.4 Packet polling procedure

See 3GPP TS 44.060 sub-clause 7.2.1.3.

7.3.2.5 Abnormal cases

See 3GPP TS 44.060 sub-clause 7.2.2.

7.3.3 Entering the MAC-Dedicated state

7.3.3.1 General

The procedure is triggered by a request from upper layers on the network side to transfer an upper layer PDU to a mobile station in MAC-Idle state. The request is implicit when receiving an upper layer PDU to a mobile station not already having any assigned radio resources and the request requires dedicated resources. Upon such a request, the network shall initiate a packet DBPSCH assignment procedure as defined in sub-clause 7.3.3.2.

7.3.3.2 Packet DBPSCH assignment procedure

The network may assign a radio resource on one or more DBPSCHs to be used for the TBF. The amount of radio resources to be reserved is a network dependent choice. The network shall not assign radio resources on more than one DBPSCH/S to the TBF.

The allocated radio resource is assigned to the mobile station in a PACKET DBPSCH ASSIGNMENT message to the mobile station. The PACKET DBPSCH ASSIGNMENT message is transmitted on the PCCCH timeslot corresponding to the PCCCH group the mobile station belongs to. The appropriate PCCCH group is calculated from the IMSI (see 3GPP TS 45.002). The behaviour of the network when the IMSI is not provided by the upper layers is implementation dependent for the calculation of the PCCCH group where the PACKET DBPSCH ASSIGNMENT message has to be sent. If the mobile station is in non-DRX mode or if the IMSI or the DRX parameters are not provided by the upper layers, there is no further restriction on what part of the downlink PCCCH timeslot this PACKET DBPSCH ASSIGNMENT message can be sent, provided that this part corresponds to one or more blocks where paging may appear. If the mobile station applies DRX, this message shall be sent in one or more PCCCH block(s) corresponding to a paging group determined for the mobile station in MAC-Idle state (see 3GPP TS 45.002). The multislot capabilities of the mobile station shall be considered.

Initial timing advance can be provided in the PACKET DBPSCH ASSIGNMENT message as Timing Advance Value field. For the case where Timing Advance Value is not provided in the assignment message, the mobile station is not allowed to send normal bursts (e.g. PACKET DOWNLINK ACK/NACK message) on the uplink until it receives a valid timing advance on the SACCH.

The mobile station shall use information received on the PBCCH to decode the channel descriptions contained in the assignment. If frequency hopping is applied, the mobile station shall use the last CA received on PBCCH to decode the Mobile Allocation. Alternatively, the network may provide a Mobile Allocation in the assignment. The radio resource is assigned to the mobile station in a PACKET DBPSCH ASSIGNMENT message. On receipt of a PACKET DBPSCH ASSIGNMENT message, the mobile station shall switch to the assigned DBPSCHs.

If the mobile station receives more than one PACKET DBPSCH ASSIGNMENT message while it monitors the PCCCH, it shall act upon the most recently received message and shall ignore the previous message.

When the PACKET DBPSCH ASSIGNMENT message is received the mobile station shall switch to the assigned DBPSCH(s), start timer T3190 and enters the MAC-Dedicated state. The timer T3190 is restarted when receiving the first valid RLC data block addressed to itself.

When the mobile station switches to the assigned DBPSCHs, it shall take the power control parameters received in the PACKET DBPSCH ASSIGNMENT message into account, perform signal strength measurements and apply output power control procedures as they are defined for MAC-Dedicated state (see 3GPP TS 45.008).

On expiry of timer T3190, the mobile station shall abort the procedure and return to MAC-Idle state.

7.3.3.3 Packet DBPSCH assignment procedure completion

The Packet DBPSCH assignment procedure is completed when the mobile station receives a valid RLC/MAC block.

7.3.3.4 Packet polling procedure

On receipt of a control message with the poll bit set, the mobile station shall respond to the network with the PACKET CONTROL ACKNOWLEDGEMENT message.

7.3.3.5 Abnormal cases

If a failure occurs on the mobile station side of the new TBF before mobile station has successfully entered the MAC-Dedicated state, the newly reserved resources are released; the subsequent behaviour of the mobile station depends on the type of failure and previous actions.

– If the mobile station has been assigned more DBPSCHs than it supports according to its MS multislot class, the mobile station shall ignore the assignment and return to MAC-Idle state.

– If the mobile station has been assigned more than one DBPSCH/S, the mobile station shall ignore the assignment and return to MAC-Idle state

– On expiry of timer T3190, the mobile station shall return to MAC-Idle state.

– If the failure is due to any other reason, the mobile station shall ignore the assignment and return to MAC-Idle state and cell reselection continues.

7.4 Procedure for measurement report sending in MAC-Idle state

7.4.1 General

The procedure for measurement report sending shall be initiated by the mobile station at expiry the NC measurement report interval timer T3158. At expiry of the timer T3158 shall restart the expired timer T3158, perform the measurements and initiate the packet access.

The procedure for measurement report sending is initiated by the mobile station on PCCCH (sub-clause 7.4.2).

If the mobile station initiates the establishment of a DBPSCH, the timer T3158 shall be stopped and no measurement reports shall be sent. When the last DBPSCH is released and if the mobile station has not changed cell, the measurement reporting procedure shall be restarted.

If a cell change has occurred while the mobile station had one or more DBPSCHs allocated, the measurements shall be cancelled until new NC orders have been received (see sub-clause 5.5).

7.4.2 Measurement report sending procedure initiated on PCCCH

7.4.2.1 General

The packet access procedure is initiated by the MAC entity in the mobile station as specified in sub-clauses 7.2.3.1 and 7.2.3.2 but with access type "Single block without TBF establishment" indicated in the PACKET CHANNEL REQUEST message.

7.4.2.2 On receipt of a PACKET CHANNEL REQUEST message

See 3GPP TS 44.060 sub-clause 7.3.1.1.

7.4.2.3 On receipt of a PACKET UPLINK ASSIGNMENT message

See 3GPP TS 44.060 sub-clause 7.3.1.2.

7.4.2.4 On receipt of a PACKET ACCESS REJECT message

See 3GPP TS 44.060 sub-clause 7.3.1.3.

7.4.2.5 Abnormal cases

See 3GPP TS 44.060 sub-clause 7.3.1.4.

7.5 Cell Change Order procedures in MAC-Idle state

7.5.1 General

For an individual mobile station in MAC-Idle state, the network may initiate the cell change order procedure on PCCCH.

The network may initiate the cell change order procedure by sending a PACKET CELL CHANGE ORDER message in a PCCCH block monitored by the mobile station. No TBF shall be established.

The PACKET CELL CHANGE ORDER message contains:

– The characteristics of the new cell that are necessary to identify it (i.e. BSIC + BCCH frequency).

– The NC measurement parameters valid for the mobile station in the new cell (NETWORK_CONTROL_ORDER and optionally: NC_NON_DRX_PERIOD, NC_REPORTING_PERIOD_I and NC_REPORTING_PERIOD_T).

For a multi-RAT mobile station, the PACKET CELL CHANGE ORDER message may contain information on a 3G target cell; in the case of UTRAN, the establishment of channel(s) and subsequent measurement reporting are defined in 3GPP TS 25.331.

Upon receipt of the PACKET CELL CHANGE ORDER message, the mobile station shall stop all relevant RLC/MAC timers except for timers related to measurement reporting and start timer T3174. The mobile station shall then switch to the specified new cell and obey the relevant RLC/MAC procedures on this new cell. If a valid RRBP field was received in the PACKET CELL CHANGE ORDER message then the MS shall send a PACKET CONTROL ACKNOWLEDMENT message in the reserved uplink radio block specified by the RRBP field before switching to the new cell. If the timers related to measurement reporting expire while the reselection procedure has not yet been completed, these timers shall be restarted so that the mobile station resumes the measurement reporting procedures once camped on the new cell. The mobile station shall obey the PACKET CELL CHANGE ORDER message irrespective of whether or not the mobile station has any knowledge of the relative synchronisation of the target cell to the serving cell. A UTRAN capable mobile station shall obey the command irrespective of whether the cell is known or not known (see 3GPP TS 25.133 and 3GPP TS 25.123).

The procedure for completion of the cell change order is defined in 3GPP TS 44.060 sub-clause 8.4.1 and abnormal procedures are defined in 3GPP TS 44.060 sub-clause 8.4.2.

7.6 Measurement Order procedures in MAC-Idle state

7.6.1 General

To send the NC Measurement order to an individual mobile station in MAC‑Idle state, the network may establish a connection on PCCCH.

7.6.2 Measurement Order procedures initiated on PCCCH

See 3GPP TS 44.060 sub-clause 7.5.1.