8 Elements for layer-to-layer communication

25.3243GPPBroadcast/Multicast Control (BMC)Release 17TS

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

8.1 Service Primitives between RRC and BMC

8.1.1 Primitives

The primitives supported at CBMC-SAP between RRC and BMC are shown in Table 8.1.1-1.

Table 8.1.1-1: Primitives between BMC and RRC

Generic Name	Parameters
CBMC-Measurement-IND	CB-Traffic-Volume
CBMC-Rx-IND	Action, DRX selection
CBMC-Config-REQ	CTCH configuration

8.1.1.1 CBMC-Measurement-IND

The CBMC-Measurement-IND primitive is used by BMC to indicate the CB traffic volume.

Primitive Type: indication.

Parameters:

CB-Traffic-Volume.

8.1.1.2 CBMC-Rx-IND

The CBMC-Rx-IND primitive is used by BMC to indicate to RRC whether CB message reception shall start or stop and indicate when CB messages of interest are arriving in the next CBS schedule period.

Primitive Type: indication.

Parameters:

Action.

DRX selection.

8.1.1.3 CBMC-Config-REQ

The CBMC-Config-REQ primitive is used by RRC to inform the BMC about the setting of the CTCH configuration.

Primitive Type: indication.

Parameters:

CTCH configuration.

8.1.2 Parameters

8.1.2.1 CB-Traffic-Volume

Expected CTCH transmission rate [kbps].

Value set: 0,1,..,32.

8.1.2.2 Action

Start CBS reception.

Stop CBS reception.

8.1.2.3 DRX selection

List of absolute CTCH BS indices which are of interest and which should be received by Layer 1.

8.1.2.4 CTCH configuration

Current CTCH-BS index, 1  i  256.

FACH identification.

Transport Format Set of the allocated FACH (TB size, TBS size, TTI).

Reserved CTCH transmission rate [kbps]: 0,1,..,32.

8.2 Service Primitives between upper layer (U-plane) and BMC

8.2.1 Primitives

The primitives supported at BMC-SAP between BMC and upper layer (U-plane) are shown in Table 8.2.1-1.

Table 8.2.1-1: Primitives between BMC and upper layer

Legend: [ ] optional parameters

Generic Name	Parameters
BMC-Data-REQ	Message-ID, [, Old-Serial-Number], New-Serial-Number, Data-Coding-Scheme, CB-Data , [Category], Repetition-Period, Number-of-Broadcasts-Requested
BMC-Data-IND	Message-ID, Serial-Number, Data-Coding-Scheme, CB-Data
BMC-Data-CNF	Message-ID, Serial-Number
BMC-Congestion-IND
BMC-Normal-IND
BMC-Activation-REQ	Message-ID (n times)
BMC-Deactivation-REQ	Message-ID (n times)
BMC-DRX-REQ	CB-DRX-Schedule-Period, Reserved-CB-Capacity
BMC-Error-IND	Cause

BMC-Data41-REQ	Transport Layer Message, Broadcast Address
BMC-Data41-IND	Transport Layer Message,
BMC-Error41-IND	Error Type

8.2.1.1 Primitives used in relation to UMTS Core Network

8.2.1.1.1 BMC-Data-REQ

The BMC-Data-REQ primitive is used by upper layer to request repeated transmission of CB messages.

Primitive Type: request.

Parameters:

Message-ID;

[Old-Serial-Number];

New-Serial-Number;

Data-Coding-Scheme;

CB-Data;

[Category];

Repetition-Period;

Number-of-Broadcasts-Requested.

8.2.1.1.2 BMC-Data-IND

The BMC-Data-IND primitive is used to indicate received CB messages (i.e. CB Data) to upper layer.

Primitive Type: indication.

Parameters:

Message-ID;

Serial-Number;

Data-Coding-Scheme;

CB-Data.

8.2.1.1.3 BMC-Data-CNF

The BMC-Data-CNF primitive is used to indicate the complete broadcast of CB messages.

Primitive Type: confirmation.

Parameters:

Message-ID.

Serial-Number.

8.2.1.1.4 BMC-Congestion-IND

The BMC-Congestion-IND primitive is used to indicate to upper layer (BM-IWF) that the BMC entity is congested.

Primitive Type: indication.

Parameters: None.

8.2.1.1.5 BMC-Normal-IND

The BMC-Normal-IND primitive is used to indicate to upper layer (BM-IWF) that the BMC has recovered from a congestion situation and is operating normal.

Primitive Type: indication.

Parameters: None.

8.2.1.1.6 BMC-Activation-REQ

The BMC-Activation-REQ primitive is used to request CB message reception and to notify which CB messages are of interest and shall be delivered to the upper layer.

Primitive Type: request.

Parameters:

Message-ID (n times).

8.2.1.1.7 BMC-Deactivation-REQ

The BMC-Deactivation-REQ primitive is used to request stop of reception of listed CB messages. If no more CB messages are to be received, CB message reception shall stop.

Primitive Type: request.

Parameters:

Message-ID (n times).

8.2.1.1.8 BMC-DRX-REQ

The BMC-DRX-REQ primitive is used to command CBS discontinuous reception (CB DRX).

NOTE: In UMTS, a Set DRX procedure is not requested for the CBC in TS 23.041. It is left to an O&M system to provide such a function or not.

Primitive Type: request.

Parameters:

CB-DRX-Schedule-Period.

Reserved-CB-Capacity.

8.2.1.1.9 BMC-Error-IND

The BMC-Error-IND primitive is used to indicate unsuccessful operations of the BMC entity requested.

Primitive Type: indication.

Parameters:

Cause.

8.2.1.2 Primitives used for ANSI-41 Core Network

8.2.1.2.1 BMC-Data41-REQ

The BMC-Data41-REQ primitive is used by upper layer (Transport Layer) to request repeated transmission of CBS messages if the source is ANSI-41 core network.

Primitive Type: request.

Parameters:

Transport Layer Message.

Broadcast Address.

8.2.1.2.2 BMC-Data41-IND

The BMC-Data-IND primitive is used to indicate received CB messages to upper layer (Transport Layer) if the source is ANSI-41 core network.

Primitive Type: indication.

Parameters:

Transport Layer Message.

Broadcast Address.

8.2.1.2.3 BMC-Error41-IND

The BMC-Error-IND primitive is used to report BMC Layer Error to the upper layer (Transport Layer) if the source is ANSI-41 core network.

Primitive Type: indication.

Parameters:

Error Type.

8.2.2 Parameters

8.2.2.1 Message-ID

Part of the CB message identification describing the source and type of a CB message.
This parameter is described in [3].

8.2.2.2 Serial Number

Part of the CB message identification describing variants of a CB message.
This parameter is described in [3].

8.2.2.3 Data-Coding-Scheme

Data coding scheme applied to the CB information.
This parameter is described in [4] and [3].

8.2.2.4 CB-Data

CB information to be broadcast.

NOTE: The relation to GSM CBS pages can be found in [6] or [3].

8.2.2.5 Category

Indicates the category (priority) of the CB message.
Values:
HIGH (CB message is to be broadcast at the earliest opportunity in the reserved CB capacity of the current CB DRX schedule period).
NORMAL (default, CB messages to be broadcast according to the associated repetition period).
BACKGROUND (CB message to be broadcast in the CB capacity not occupied by HIGH or NORMAL CB messages within a CB DRX schedule period).

This parameter is described in [3].

8.2.2.6 Repetition-Period

Indicates the period of time after which broadcast of the CB message should be repeated.
This parameter is described in [3].

NOTE: For GSM, the repetition period is a multiple of 1.883 seconds (cf. [3]).

8.2.2.7 Number-of-Broadcasts-Requested

Number of times a CB message is to be broadcast.
Values:
0 indefinitely.
n, 1  n  65535 finite number of times to be broadcast.

This parameter is described in [3].

8.2.2.8 CB-DRX-Schedule-Period

Indication of the CB DRX schedule period length.

8.2.2.9 Reserved-CB-Capacity

Indicates the capacity reserved for CB messages with Category = HIGH or new CB messages.

8.2.2.10 Cause

CB message already stored.

Old CB message not stored.

8.2.2.11 Transport Layer Message

This parameter is described in [8].

8.2.2.12 Broadcast Address

This parameter is described in [8].

8.2.2.13 Error Type

The error codes shall be SMS_CauseCode values as defined in the SMS_CauseCode Table in [7].