[2] WCDMA Protocol Layer2 BMC

WCDMA Protocol: Layer2- BMC protocol specification(3GPP TSG 25.324)

Samsung Electronics

WCDMA Development Team

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Model of BMCuser-plane

RRC

BMC-SAP L2/BMC sublayer CBMCSAP BMC

UM

One BMC protocol entity per cell. Each BMC entity requires a single CTCH, Unacknowledged Mode

L2/RLC sublayer RLC

CTCH-SAP

WCDMA Development Team

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Functions Storage of Cell Broadcast Messages. Traffic volume monitoring and radio resource request for CBS. Scheduling of BMC messages. Transmission of BMC messages to UE. Delivery of Cell Broadcast messages to upper layer (NAS)

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Elements for layer to layer communication Service Primitives between RRC and BMCGeneric Name CBMC-Measurement-IND CBMC-Rx-IND CBMC-Config-REQ Parameters CB-Traffic-Volume Action, DRX selection CTCH configuration

CB-Traffic-Volume Expected CTCH transmission rate [kbps]. Value set: 0,1,..,32. Action Start CBS reception. Stop CBS reception. DRX selection List of absolute CTCH BS indices which are of interest and which should be received by Layer 1. CTCH configuration Current CTCH-BS index, 1 e i e 256. FACH identification. Transport Format Set of the allocated FACH (TB size, TBS size, TTI). Reserved CTCH transmission rate [kbps]: 0,1,..,32. 4

WCDMA Development Team

Elements for layer to layer communication Service Primitives between upper layer (U-plane) and BMCGeneric Name BMC-Data-REQ Parameters Message-ID, [Old-Serial-Number], New-Serial-Number Data-Coding-Scheme, CB-Data, [Category] Repetition-Period, Number-of-Broadcasts-Requested Message-ID, Serial-Number, Data-Coding-Scheme, CB-Data Message-ID, Serial-Number

BMC-Data-IND BMC-DataBMC-Data-CNF BMC-Congestion-IND BMC-Normal-IND BMC-Activation-REQ BMC-Deactivation-REQ BMC-DRX-REQ BMC-Error-IND BMC-Data41-REQ BMC-Data41-IND BMC-Error41-IND WCDMA Development Team

Message-ID (n times) Message-ID (n times) CB-DRX-Schedule-Period, Reserved-CB-Capacity Cause Transport Layer Message, Broadcast Address Transport Layer Message Error Type

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ProceduresUE UTRAN

BMC message

BMC Message Broadcast This procedure is used for broadcasting BMC messages from the network to UEs in a cell. A UE supporting Cell Broadcast Service (CBS) shall be capable to receive BMC messages in the Idle mode and in CELL_PCH and URA_PCH RRC-states of Connected mode.Service

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Generation of Schedule message Input parameters of the scheduling procedure The CBC input parameters are: CB messages (i.e. BMC SDUs), Message Identifier per CB message, Serial Number per CB message, CB repetition period per CB message, Number of Broadcast Requested per CB message.

The RRC input parameters are: Sizes of CTCH Block Sets, Timing of CTCH Block Set sequence.

The O&M (BMC) input parameters are: DRX Schedule Period (cell related parameter) requested optionally, Reserved CB Capacity (cell related parameter) requested optionally.

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BMC Messages A BMC message is equivalent with a BMC PDU. Three types of BMC messages defined: CBS messages, CBS41 messages, Schedule messages

BMC messages specified by tabular format consist of an ordered sequence IE1,..,IEn Let (A1,IE,..,AN,IE) be the bit string of an information element IE. A1,IE : leftmost bit of the information element field AN,IE rightmost bit of the information element field.

The bit string of a BMC message is defined as the concatenation (A1,IE1,..,AN,IE1), , (A1,IEn,..,AN,IEn) of the bit strings of the IEs maintaining the sequence order.WCDMA Development Team

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BMC Messages BMC CBS Message

Information Element Message Type Message ID Serial Number Data Coding Scheme CB Data

Need MP MP MP MP MP

Multi

Type and reference

Semantics description

Enumerated (0 .. 255) Bitstring(16) Bitstring(16) Bitstring(8) Bitstring(N*8) Nu1

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BMC Messages BMC Schedule MessageInformation Element Message Type Offset to Begin CTCH BS index Need MP MP Multi Type and reference Semantics description Schedule Message Enumerated (0 .. 255) Integer (1..255)

Pointer to the first CTCH BS of the next CBS Schedule Period relative to the CTCH BS index of the current BMC Schedule Message

Length of CBS Scheduling Period New Message Bitmap Message Description

MP MP MP 1 to

Integer(1..256) Bitmap(N*8) Sec. 11.9 Message Description IE is included for each new message (1 in the New message bitmap) as well as for each old message (0 in the New message bitmap). The i-th Message Description IE refers to the i-th bit in the New Message Bitmap IE

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BMC Messages Coding of New Message Bitmap IECTCH BS index B CTCH BS index B+1 CTCH BS index B+2 ... 1

2

...

...

CTCH BS index E-1

CTCH BS index E

0

0

0

0

n

Legend: E

B First CTCH BS index of the CBS schedule period, 1 e B e 256 Last CTCH BS index of the CBS schedule period, E = B + Length of CBS Schedule Period 1

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BMC Messages CTCH BS Index i: Bit i of the New CBS Message Bitmap refers to the content of CTCH BS index i. Its meaning is as follows:1 The CTCH BS index i contains a BMC Message partly or completely which was either not sent during the previous schedule period, or sent unscheduled during the preceding schedule period; or, the CTCH BS is indicated as of free usage, reading advised; or it contains the Schedule Message partly or complete of the following CBS schedule period, or it contains a CBS41 Message partly or complete. The value is 1 both for the first transmission of a given BMC message in the CBS schedule period or a repetition of it within the CBS schedule period. 0 The CTCH BS is such that value 1 is not suitable.

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BMC Messages CTCH BS Index i:Information Element Message Description Type Message ID Need MP CV MDT1 (Type 1 or 5) Multi Type and reference Enumerated (0 .. 255) Enumerated (0 .. 2^16-1) Semantics description

Offset to CTCH BS index of first transmission

CV MDT2 (Type 0 or 4)

Integer(0..255)

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BMC Messages Encoding of Message Description TypeValue 0 1 2 3 4 5 6 7 8 9.. 255 Explanation Repetition of new BMC message within schedule period New message Reading advised Reading optional Repetition of old BMC message within schedule period Old message (repetition of a message sent in a previous schedule period) Schedule message CBS41 message no message Reserved for future use (IEs received with this value will be replaced by value 3)

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BMC Messages BMC CBS41 Message

Information Element Message Type Broadcast Address CB Data41

Need MP MP MP

Multi

Type and reference Sec. 11.1 Sec. 11.10 Sec. 11.11

Semantics description

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