Content for  TS 23.041  Word version:  18.4.0

The requirements are described by primitives. The term primitive is used to indicate "an abstract, implementation independent interaction between a service user and a service provider" (see ITU-T Recommendation X.210 [12]). For the CBC-BSC/RNC/MME or CBCF-AMF interface, the service provider would be the protocol interconnecting the CBC and BSC/RNC/MME or the CBCF and AMF. A Primitive may therefore be viewed as an abstract, implementation independent request/indication or response/confirm interaction between the service user (CBC/CBCF or BSC/RNC/MME/AMF) and the service provider (protocol). A set of primitives for use between the CBC and BSC/RNC/MME and CBCF and AMF are specified appropriate to the functionality assigned to the CBC/CBCF and BSC/RNC/MME/AMF in clause 5 and clause 6. In order to allow future extensions to the primitives, where possible a primitive shall not be rejected because a parameter is not recognized; the recipient shall ignore the parameter in question and process the remainder of the primitive's parameters as usual. The following table gives an overview over the existing primitives:

  In GSM the CBC is integrated into the Core Network. The protocol between the CBC and BSC is defined in TS 48.049. In UMTS the CBC is integrated into the Core Network. The protocol between the CBC and RNC is defined in TS 25.419. In E-UTRAN the CBC is integrated into the Core Network. The protocol between the CBC and MME is defined in TS 29.168. In NG-RAN the CBCF/PWS-IWF is integrated into the Core Network. The protocol between the CBCF/PWS-IWF and AMF is defined in TS 29.518.

In GSM within a CBC-BSC interface, a CBS message is uniquely identified by the quartet (Message Identifier, Serial Number, Cell Identifier, Channel Indicator). In UMTS within the CBC-RNC interface, in E-UTRAN within the CBC-MME interface, and in NG-RAN within the CBCF-AMF interface and CBC - PWS-IWF interface, a CBS message is uniquely identified by the triplet (Message Identifier, Serial Number, Cell Identifier). This means that even when two CBS messages have the same semantic contents (for example the same weather forecast) but in different languages or coding schemes, they are considered as different and must therefore be identified by a different quartet. The Serial Number (Old-Serial-Number or New-Serial-Number) is managed cyclically and therefore this does not prevent the re-use of the same quartet for a different CBS message when the serial number have been incremented a sufficient number of times. How to manage the ambiguity is described subsequently. This unique identification of a CBS message across the CBC-BSC interface is used in all the primitives defined hereafter. This means that the quartet/triplet will be implicitly or explicitly present in every interface primitive which applies to a given CBS message. This unique quartet/triplet will be referred in the rest of the document as the "message reference".

This primitive is sent by the CBC to the BSC/RNC. As this primitive can be used either to broadcast a new CBS message or replace a CBS message already broadcast, the CBC will use the presence and content of the Old-Serial-Number and New-Serial-Number fields in this primitive to instruct the BSC/RNC as follows: All cells which should perform the broadcasting are mentioned in the Cell-List parameter. The broadcast of the referenced CBS message in the cells which are not mentioned in the Cell-List remains unaffected. If no category is present, the default category is interpreted by the BSC/RNC, see the parameter clause. This primitive is responded by a REPORT or REJECT primitive.

  This primitive is sent by the CBC to the BSC/RNC. The CBC will use this primitive to kill the message indicated by the combination of message identifier, serial number, GSM only [Channel Indicator] and the cells indicated in the Cell-List of this KILL request, i.e. the primitive will halt broadcast of the message in the indicated cells and remove any knowledge of the message from the BSC/RNC for these cells. The broadcast of the referenced message in the cells which are not mentioned in the Cell-List remains unaffected. This primitive is responded with a REPORT or REJECT primitive.

  This primitive will be sent by the BSC/RNC to the CBC in response to WRITE-REPLACE and KILL primitives. The Serial-Number field will contain the old serial number if this primitive is sent in response to a KILL primitive, and the new serial number if the primitive is sent in response to a WRITE-REPLACE primitive. The No-of-Broadcasts-Completed-List, if present, may contain for each cell the number of broadcasts of the (replaced or killed) CB message with the old message reference sent to this particular cell for broadcast. The serial number information element in the case of a WRITE-REPLACE does not refer to the message for which the number of broadcasts completed information is supplied. The Failure-List, if present, may contain those cells which were present in the related WRITE-REPLACE or KILL primitive and failed the requested operation.

  This primitive is sent by the CBC to the BSC/RNC in order to obtain the current loading of the CBCH/UTRAN Radio Resource of particular cells referenced in the Cell-List parameter. This primitive is responded by a STATUS-LOAD-QUERY Response/Confirm or a REJECT primitive.

  This primitive will be sent by the BSC/RNC in response to the STATUS-LOAD-QUERY Request/Indication primitive. The Radio-Resource-Loading-List, if present, may contain each cell which successfully performed the requested operation and for each of these cells the CBCH loading/ UTRAN Radio Resource loading of this particular cell. The Radio-ResourceLoading-List will not be present if all cells indicated in the related STATUS-LOAD-QUERY Request/Indication failed the requested operation. The Failure-List, if present, may contain all cells for which the requested operation failed (e.g. because the cells CBCH is not available in a BTS). The STATUS-LOAD-QUERY Response/Confirm will not contain the Failure-List parameter if none of the cells in the Cell-List of the related STATUS-LOAD-QUERY Request failed the requested operation.

  This primitive is sent by the CBC to the BSC/RNC in order to obtain the current status of a CB-message for the cells referenced in the Cell-List parameter. This primitive is responded by the STATUS-MESSAGE-QUERY Response/Confirm or by a REJECT Response/Confirm.

  This primitive will be sent by the BSC/RNC to the CBC in response to a STATUS-MESSAGE-QUERY Request/Indication primitive. The No-of-Broadcasts-Completed-List, if present, may contain each cell which successfully performed the requested operation and for each of these cells the number of times this CB message has been sent to this particular cell for broadcast (parameter Number-of-Broadcasts-Completed; this parameter is not included for the cell if the old message reference is not known to the BSC/RNC, and an entry is made in the failure list). The No-of-Broadcasts-Completed-List will not be present if all cells indicated in the related STATUS-MESSAGE-QUERY Request failed the requested operation. The Failure-List may contain all cells for which the requested operation failed (e.g. because the broadcast of the requested message was never requested before or because the cells CBCH is not available). The STATUS-MESSAGE-QUERY Response/Confirm will not contain the Failure-List parameter if none of the cells in the Cell-List of the related STATUS-MESSAGE-QUERY Request failed the requested operation.

  This primitive is sent by the BSC/RNC to the CBC in response to any primitive which is not understood (e.g. invalid parameter or parameter value).