11.2.5 Packet Channel Request

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 is sent in random mode on the PRACH using the PRACH uplink block format defined in 3GPP TS 44.004. The order of bit transmission is defined in 3GPP TS 44.004. The numbering, assembling and field mapping conventions defined for RLC/MAC control blocks in sub-clause 10.0b shall apply.

The message format is either 11-bit or 8-bit. The mobile station shall use the format indicated by the System Information parameter ACCESS_BURST_TYPE

The 11-bit format is coded as shown in table 11.2.5.1.

The 8-bit format is coded as shown in table 11.2.5.2.

Table 11.2.5.1: PACKET CHANNEL REQUEST 11 bit message content

< Packet channel request 11 bit message content > ::=

< One Phase Access Request : 0 < MultislotClass : bit (5) >

< Priority : bit (2) >

< RandomBits : bit (3) > >

| < Short Access Request : 100 — The value 100 was allocated in an earlier version of the protocol and shall not be used by the mobile station

< NumberOfBlocks : bit (3) >

< Priority : bit (2) >

< RandomBits : bit (3) > >

| < Two Phase Access Request : 110000 < Priority : bit (2) >

< RandomBits : bit (3) > >

| < Page Response : 110001 < RandomBits : bit (5) > >

| < Cell Update : 110010 < RandomBits : bit (5) > >

| < MM Procedure : 110011 < RandomBits : bit (5) > >

| < Single Block Without TBF Establishment : 110100 < RandomBits : bit (5) > >

| < One Phase Access Request in RLC unack mode : 110101 < RandomBits : bit (5) > >

| < Dedicated channel request : 110110 < RandomBits : bit (5) > >

| < Emergency call : 110111 < RandomBits : bit (5) > >

| < Single block MBMS access : 111000 < RandomBits : bit (5) > > ;

Table 11.2.5.2: PACKET CHANNEL REQUEST 8 bit message content

< Packet channel request 8 bit message content > ::=

< One Phase Access Request : 1 < MultislotClass : bit (5) >

< RandomBits : bit (2) > >

| < Short Access Request : 00 — The value 00 was allocated in an earlier version of the protocol and shall not be used by the mobile station

< NumberOfBlocks : bit (3) >

< RandomBits : bit (3) > >

| < Two Phase Access Request : 01000 < RandomBits : bit (3) > >

| < Page Response : 01001 < RandomBits : bit (3) > >

| < Cell Update : 01010 < RandomBits : bit (3) > >

| < MM Procedure : 01011 < RandomBits : bit (3) > >

| < Single Block Without TBF Establishment : 01100 < RandomBits : bit (3) > >

| < One phase Access Request in RLC unack mode : 011010 < RandomBits : bit (2) > >

| < Dedicated channel request : 011011 < RandomBits : bit (2) > >

| < Emergency call : 011100 < RandomBits : bit (2) > >

| < Single block MBMS access : 01111 < RandomBits : bit (3) > >;

Table 11.2.5.3: PACKET CHANNEL REQUEST details

MultislotClass (5 bit field)
This information field indicates the GPRS multislot class of the MS. The multislot class indicated by this field shall be the same as the GPRS multislot class indicated in the MS Radio Access Capability IE (see 3GPP TS 24.008). The coding is defined in the following table.

bit
5 4 3 2 1
0 0 0 0 0 multislot class 1
0 0 0 0 1 multislot class 2
: : : :
1 1 1 0 0 multislot class 29
other reserved values

Priority (2 bit field)
This information field indicates the requested Radio Priority. This field is coded as shown in the following table. The 8 bit format has a default Radio Priority of 4.

bit
2 1
0 0 Radio Priority 1 (Highest priority)
0 1 Radio Priority 2
1 0 Radio Priority 3
1 1 Radio Priority 4 (Lower priority)

NumberOfBlocks (3 bit field)
This information field indicates the number of blocks requested during a mobile originated Temporary Block Flow. This field is coded as shown in the following table:

bit
3 2 1
0 0 0 1 RLC data block
0 0 1 2 RLC data blocks
. . .
1 1 1 8 RLC data blocks

RandomBits (2 bit field or 3 bit field or 5 bit field)
This is an unformatted field.