08.183GPPBase Station System (BSS) - Serving GPRS Support Node (SGSN)BSS GPRS ProtocolGeneral Packet Radio Service (GPRS)Release 1999TS

10.1 General Structure Of A PDU

Refer to General Structure Of A PDU/3GPP TS 08.16 [16].

10.2 PDU functional definitions and contents at RL and BSSGP SAPs

10.2.1 DL-UNITDATA

This PDU is sent to the BSS to transfer an LLC-PDU across the radio interface to an MS.

PDU type: DL-UNITDATA

Direction: SGSN to BSS

Table 10.1: DL-UNITDATA PDU contents

a) The field shall be present if there is valid MS Radio Access Capability information known by the SGSN; the field shall not be present otherwise.

10.2.2 UL-UNITDATA

This PDU transfers an MS’s LLC-PDU and its associated radio interface information across the Gb-interface.

PDU type: UL-UNITDATA

Direction: BSS to SGSN

Table 10.2: UL-UNITDATA PDU content

10.2.3 RA-CAPABILITY

This PDU informs the BSS of the new Radio Access Capability of an MS.

PDU type: RA-CAPABILITY

Direction: SGSN to BSS

Table 10.3: RA-CAPABILITY PDU content

10.2.4 PTM-UNITDATA

This shall be developed in GPRS phase 2.

10.3 PDU functional definitions and contents at GMM SAP

10.3.1 PAGING PS

This PDU indicates that a BSS shall initiate the packet paging procedure for an MS within a group of cells.

PDU type: PAGING PS

Direction: SGSN to BSS

Table 10.4: PAGING PS PDU content

a) One and only one of the conditional IEs shall be present. No repeated instances of the conditional IEs are permissible (e.g. one and only one Location Area shall be present).

10.3.2 PAGING CS

This PDU indicates that a BSS shall initiate a circuit-switched paging procedure for an MS within a group of cells.

PDU type: PAGING CS

Direction: SGSN to BSS

Table 10.5: PAGING CS PDU content

a) One and only one of the conditional IEs shall be present. No repeated instances of the conditional IEs are permissible (e.g. one and only one Location Area shall be present).

NOTE: These fields are provided by the MSC via the Gs-Interface.

10.3.3 RA-CAPABILITY-UPDATE

This PDU requests that the SGSN send an MS’s current Radio Access capability or IMSI to the BSS.

PDU type: RA-CAPABILITY-UPDATE

Direction: BSS to SGSN

Table 10.6: RA-CAPABILITY-UPDATE PDU content

10.3.4 RA-CAPABILITY-UPDATE-ACK

This PDU provides the BSS with an MS’s current Radio Access capability and IMSI.

PDU type: RA-CAPABILITY-UPDATE-ACK

Direction: SGSN to BSS

Table 10.7: RA-CAPABILITY-UPDATE-ACK PDU content

a) If RA-Cap-UPD-CAUSE indicates failure of the RA-CAPABILITY-UPDATE procedure due to TLLI unknown in SGSN the IMSI IE will not be present. Otherwise, the IMSI will be present.

10.3.5 RADIO-STATUS

This PDU indicates that an exception condition related to the radio interface has occurred.

PDU type: RADIO-STATUS

Direction: BSS to SGSN

Table 10.8: RADIO STATUS PDU content

a) One and only one of the conditional IEs shall be present.

10.3.6 SUSPEND

This PDU indicates that an MS wishes to suspend its GPRS service.

PDU type: SUSPEND

Direction: BSS to SGSN

Table 10.9: SUSPEND PDU content

10.3.7 SUSPEND-ACK

This PDU positively acknowledges the reception of a SUSPEND PDU for an MS.

PDU type: SUSPEND-ACK

Direction: SGSN to BSS

Table 10.10: SUSPEND-ACK PDU content

10.3.8 SUSPEND-NACK

This PDU negatively acknowledges the reception of a SUSPEND PDU for an MS.

PDU type: SUSPEND-NACK

Direction: SGSN to BSS

Table 10.11: SUSPEND-NACK PDU content

10.3.9 RESUME

This PDU indicates that an MS wishes to RESUME its GPRS service.

PDU type: RESUME

Direction: BSS to SGSN

Table 10.12: RESUME PDU content

10.3.10 RESUME-ACK

This PDU positively acknowledges the reception of a RESUME PDU for an MS.

PDU type: RESUME-ACK

Direction: SGSN to BSS

Table 10.13: RESUME-ACK PDU content

10.3.11 RESUME-NACK

This PDU negatively acknowledges the reception of a RESUME PDU for an MS.

PDU type: RESUME-NACK

Direction: SGSN to BSS

Table 10.14: RESUME-NACK PDU content

10.4 PDU functional definitions and contents at NM SAP

10.4.1 FLUSH-LL

This PDU informs a BSS that an MS has moved from one cell to another.

PDU type: FLUSH-LL

Direction: SGSN to BSS

Table 10.15: FLUSH LL PDU content

10.4.2 FLUSH-LL-ACK

This PDU indicates that LLC-PDU(s) buffered for an MS in the old cell have been either deleted or transferred to the new cell within the NSE.

PDU type: FLUSH-LL-ACK

Direction: BSS to SGSN

Table 10.16: FLUSH LL ACK PDU content

10.4.3 LLC-DISCARDED

This PDU indicates that a number of buffered LLC-PDUs in a cell for an MS have been deleted inside the BSS (because of PDU Lifetime expiration or Cell-reselection for example).

PDU type: LLC-DISCARDED

Direction: BSS to SGSN

Table 10.17: LLC DISCARDED PDU content

10.4.4 FLOW-CONTROL-BVC

This PDU informs the flow control mechanism at an SGSN of the status of a BVC’s maximum acceptable SGSN to BSS throughput on the Gb interface.

PDU type: FLOW-CONTROL-BVC

Direction: BSS to SGSN

Table 10.18: FLOW-CONTROL-BVC PDU content

10.4.5 FLOW-CONTROL-BVC-ACK

This PDU informs the flow control mechanism at the BSS that the SGSN has received the FLOW-CONTROL-BVC PDU indicated by the Tag.

PDU type: FLOW-CONTROL-BVC-ACK

Direction: SGSN to BSS

Table 10.19: FLOW-CONTROL-BVC-ACK PDU content

10.4.6 FLOW-CONTROL-MS

This PDU informs the flow control mechanism at an SGSN of the status of an MS’s maximum acceptable SGSN to BSS throughput on the Gb interface.

PDU type: FLOW-CONTROL-MS

Direction: BSS to SGSN

Table 10.20: FLOW-CONTROL-MS PDU content

10.4.7 FLOW-CONTROL-MS-ACK

This PDU informs the flow control mechanism at the BSS that the SGSN has received the FLOW-CONTROL-MS PDU indicated by the TLLI and the Tag.

PDU type: FLOW-CONTROL-MS-ACK

Direction: SGSN to BSS

Table 10.21: FLOW-CONTROL-MS-ACK PDU content

10.4.8 BVC-BLOCK

This PDU indicates that the contained BVC shall be blocked at the recipient entity.

PDU type: BVC-BLOCK

Direction: BSS to SGSN

Table 10.22: BVC-BLOCK PDU content

10.4.9 BVC-BLOCK-ACK

This PDU acknowledges that a BVC has been blocked.

PDU type: BVC-BLOCK-ACK

Direction: SGSN to BSS

Table 10.23: BVC-BLOCK-ACK PDU content

10.4.10 BVC-UNBLOCK

This PDU indicates that the identified BVC shall be unblocked at the recipient entity.

PDU type: BVC-UNBLOCK

Direction: BSS to SGSN

Table 10.24: BVC-UNBLOCK PDU content

10.4.11 BVC-UNBLOCK-ACK

This PDU acknowledges that a BVC has been unblocked.

PDU type: BVC-UNBLOCK-ACK

Direction: SGSN to BSS

Table 10.25: BVC-UNBLOCK-ACK PDU content

10.4.12 BVC-RESET

This PDU indicates that BVC initialisation is required, e.g. because of a BVC failure.

PDU type: BVC-RESET

Direction: SGSN to BSS, BSS to SGSN

Table 10.26: BVC-RESET PDU content

a) The Cell Identifier IE is mandatory in the BVC-RESET PDU sent from BSS to SGSN in order to reset a BVC corresponding to a PTP functional entity. The Cell Identifier IE shall not be used in any other BVC-RESET PDU.

b) The Feature bitmap is only sent in a BVC-RESET PDU related to the signalling BVC. Absence of this IE implies no optional features are available over the NSE.

10.4.13 BVC-RESET-ACK

This PDU indicates that BVC initialisation has been executed.

PDU type: BVC-RESET-ACK

Direction: BSS to SGSN, SGSN to BSS

Table 10.27: BVC-RESET-ACK PDU content

a) The Cell Identifier IE is mandatory in the BVC-RESET-ACK PDU sent from BSS to SGSN in response to reset a BVC corresponding to a PTP functional entity. The Cell Identifier IE shall not be used in any other BVC-RESET-ACK PDU.

b) The Feature bitmap is only sent in a BVC-RESET-ACK PDU related to the signalling BVC. Absence of this IE implies no optional features are available over the NSE.

10.4.14 STATUS

This PDU indicates that an exception condition occurred.

PDU type: STATUS

Direction: SGSN to BSS, BSS to SGSN

Table 10.28: STATUS PDU content

a) This is the whole PDU (starting with the [PDU type]) within which an error was detected. This PDU may be truncated if it exceeds the information carrying capacity of the underlying network service.

10.4.14.1 Static conditions for BVCI

The "BVCI" IE shall be included when the "Cause" IE is set to one of the following values:

a) "BVCI blocked";

b) "BVCI unknown";

and shall not be included otherwise.

10.4.15 SGSN-INVOKE-TRACE

This PDU indicates that the BSS shall begin the production of a trace record for an MS.

PDU type: SGSN-INVOKE-TRACE

Direction: SGSN to BSS

Table 10.29: SGSN-INVOKE-TRACE PDU content

10.4.16 DOWNLOAD-BSS-PFC

This PDU requests a SGSN to initiate a CREATE-BSS-PFC procedure.

PDU type: DOWNLOAD-BSS-PFC

Direction: BSS to SGSN

Table 10.30: DOWNLOAD-BSS-PFC PDU content

10.4.17 CREATE-BSS-PFC

This PDU allows the SGSN to request that a BSS create or modify a BSS Packet Flow Context.

PDU type: CREATE-BSS-PFC

Direction: SGSN to BSS

Table 10.31: CREATE-BSS-PFC PDU content

10.4.18 CREATE-BSS-PFC-ACK

This PDU allows the BSS to acknowledge a request from the SGSN for the creation or modification of a BSS Packet Flow Context.

PDU type: CREATE-BSS-PFC-ACK

Direction: BSS to SGSN

Table 10.32: CREATE-BSS-PFC-ACK PDU content

10.4.19 CREATE-BSS-PFC-NACK

This PDU allows the BSS to Nack a request from the SGSN for the creation of a BSS Packet Flow Context.

PDU type: CREATE-BSS-PFC-NACK

Direction: BSS to SGSN

Table 10.33: CREATE-BSS-PFC-NACK PDU content

10.4.20 MODIFY-BSS-PFC

This PDU allows the BSS to request a modification of a BSS Packet Flow Context.

PDU type: MODIFY-BSS-PFC

Direction: BSS to SGSN

Table 10.34: MODIFY-BSS-PFC PDU content

10.4.21 MODIFY-BSS-PFC-ACK

This PDU allows the SGSN to acknowledge a modification to a BSS Packet Flow Context.

PDU type: MODIFY-BSS-PFC-ACK

Direction: SGSN to BSS

Table 10.35: MODIFY-BSS-PFC-ACK PDU content

10.4.22 DELETE-BSS-PFC

This PDU allows the SGSN to request that a BSS delete a BSS Packet Flow Context.

PDU type: DELETE-BSS-PFC

Direction: SGSN to BSS

Table 10.37: DELETE-BSS-PFC PDU content

10.4.23 DELETE-BSS-PFC-ACK

This PDU allows the BSS to acknowledge a request for the deletion of a BSS Packet Flow Context.

PDU type: DELETE-BSS-PFC-ACK

Direction: BSS to SGSN

Table 10.38: DELETE-BSS-PFC-ACK PDU content