11.2.28b Packet DBPSCH Uplink Ack/Nack Type 2

3GPP44.060General Packet Radio Service (GPRS)Mobile Station (MS) - Base Station System (BSS) interfaceRadio Link Control / Medium Access Control (RLC/MAC) protocolRelease 17TS

This message shall only be used when FLO is used. It is sent on ADCH from the network to the mobile station to indicate the status of uplink RLC data blocks received.

Message type: PACKET DBPSCH UPLINK ACK/NACK TYPE 2

Direction: network to mobile station

Classification: DBPSCH message

Table 11.2.28b.1: Packet DBPSCH UPLINK Ack/Nack TYPE 2information elements

< Packet DBPSCH Uplink Ack/Nack message content > ::=

{ < MESSAGE_TYPE : bit (6) == 001001 > — The same message type as for Packet DBPSCH Uplink Ack/Nack is — used since these two messages are mutually exclusive.

< RB Id : bit (5) >

{ 0 — UDCH TBF mode

{ 0 — All data blocks acknowledged, no retransmission requested

| 1 < FLO Ack/Nack Description : < FLO Ack/Nack Description IE > > }

| 1 — CDCH TBF mode

{ 0 — All data blocks acknowledged, no retransmission requested

| 1 < STARTING_SEQUENCE_NUMBER : bit (4) >

< RECEIVED_BLOCK_BITMAP : bit (8) > } }

< padding bits > 

! < DBPSCH message part error : bit (*) = < no string > > } ;

Table 11.2.28b.2: Packet DBPSCH UPLINK Ack/Nack TYP2 2 information element details

RB Id (5 bit field)
This field contains the radio bearer identity of the mobile station’s radio bearer for which the uplink data transfer is acknowledged. This field is encoded as a binary number with range 0-31.

STARTING_SEQUENCE_NUMBER (4 bit field)
The SSN contains the value of V(R) when this information element was transmitted. This field is encoded as the binary representation of V(R).
Range 0 to 15 (4 bit field)

RECEIVE_BLOCK_BITMAP (RBB) (128 or 8 bit field)
The RBB is a bitmap representing Block Sequence Numbers. The bitmap is indexed relative to SSN as follows:

BSN = (SSN – bit_number) modulo 16, for bit_number = 1 to 8 (8 bit field).

The BSN values represented range:

from (SSN – 1) mod 16 to (SSN – 8) mod 16 (8 bit field)

The value of each bit represents the acknowledgement status of the RLC data block with:

BSN = (SSN – bit_number) mod 16 (8 bit field),

it is encoded as follows:

0 Negative acknowledgement

1 Positive acknowledgement