ETSI TS 148 049 V13.0.0 (2016-01)

ETSI TS 1148 049 V13.0.0 (201616-01)

TECHNICAL SPECIFICATIONION
Digital cellular telecocommunications system (Phahase 2+);
Base Station Controlleller - Cell Broadcast Centre (B (BSC-CBC)
interterface specification;
Cell Broadccasta Service Protocol (CBSP) P)
(3GPP TS 48.0.049 version 13.0.0 Release 13 13)

R
GLOBAL SYSTTEME FOR
MOBILE COMMUUNNICATIONS
3GPP TS 48.049 version 13.0.0 Release 13 1 ETSI TS 148 049 V13.0.0 (2016-01)

Reference
RTS/TSGG-0248049vd00
Keywords
GSM
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3GPP TS 48.049 version 13.0.0 Release 13 2 ETSI TS 148 049 V13.0.0 (2016-01)
Intellectual Property Rights
IPRs essential or potentially essential to the present document may have been declared to ETSI. The information
pertaining to these essential IPRs, if any, is publicly available for ETSI members and non-members, and can be found
in ETSI SR 000 314: "Intellectual Property Rights (IPRs); Essential, or potentially Essential, IPRs notified to ETSI in
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server) which are, or may be, or may become, essential to the present document.
Foreword
This Technical Specification (TS) has been produced by ETSI 3rd Generation Partnership Project (3GPP).
The present document may refer to technical specifications or reports using their 3GPP identities, UMTS identities or
GSM identities. These should be interpreted as being references to the corresponding ETSI deliverables.
The cross reference between GSM, UMTS, 3GPP and ETSI identities can be found under
http://webapp.etsi.org/key/queryform.asp.
Modal verbs terminology
In the present document "shall", "shall not", "should", "should not", "may", "need not", "will", "will not", "can" and
"cannot" are to be interpreted as described in clause 3.2 of the ETSI Drafting Rules (Verbal forms for the expression of
provisions).
"must" and "must not" are NOT allowed in ETSI deliverables except when used in direct citation.
ETSI
3GPP TS 48.049 version 13.0.0 Release 13 3 ETSI TS 148 049 V13.0.0 (2016-01)
Contents
Intellectual Property Rights . 2
Foreword . 2
Modal verbs terminology . 2
Foreword . 6
1 Scope . 7
2 References . 7
3 Definitions and abbreviations . 7
3.1 Definitions . 7
3.2 Abbreviations . 8
4 General . 9
4.1 Procedure Specification Principles . 9
4.2 Specification Notations . 9
5 Transport and Data Link layer . 9
5.1 General . 9
5.2 TCP /IP . 10
5.3 Data Link layer . 10
6 Functions of CBSP . 10
7 CBSP Procedures . 11
7.1 Elementary Procedures . 11
7.2 Write-Replace . 11
7.2.1 General . 11
7.2.2 Successful Operation . 12
7.2.2.1 General . 12
7.2.2.2 Broadcast request of a CBS message . 12
7.2.2.3 Broadcast request of an emergency message . 13
7.2.2.4 Returning WRITE-REPLACE COMPLETE message to CBC . 14
7.2.3 Unsuccessful Operation . 15
7.3 Kill. 16
7.3.1 General . 16
7.3.2 Successful Operation . 16
7.3.2.1 General . 16
7.3.2.2 Termination of CBS message broadcast . 16
7.3.2.3 Termination of emergency message broadcast. 16
7.3.3 Unsuccessful Operation . 17
7.4 Load Status Enquiry . 17
7.4.1 General . 17
7.4.2 Successful Operation . 18
7.4.3 Unsuccessful Operation . 19
7.5 Message Status Query . 19
7.5.1 General . 19
7.5.2 Successful Operation . 20
7.5.3 Unsuccessful Operation . 21
7.6 Set DRX . 21
7.6.1 General . 21
7.6.2 Successful Operation . 22
7.6.3 Unsuccessful Operation . 23
7.7 Reset . 23
7.7.1 General . 23
7.7.2 Successful Operation . 24
7.7.3 Unsuccessful Operation . 24
7.7a Keep Alive. 25
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7.7a.1 General . 25
7.7a.2 Successful Operation . 25
7.7a.3 Unsuccessful Operation . 26
7.8 Restart Indication . 26
7.8.1 General . 26
7.8.2 Successful Operation . 26
7.9 Failure Indication . 27
7.9.1 General . 27
7.9.2 Successful Operation . 27
7.10 Error Indication . 27
7.10.1 General . 27
7.10.2 Successful Operation . 28
8 Elements for CBSP Communication . 28
8.1 Message Functional Definitions and Contents . 28
8.1.1 General . 28
8.1.2 Presence . 29
8.1.3 Message Contents . 29
8.1.3.1 WRITE-REPLACE . 29
8.1.3.2 WRITE-REPLACE COMPLETE . 30
8.1.3.3 WRITE-REPLACE FAILURE . 31
8.1.3.4 KILL . 32
8.1.3.5 KILL COMPLETE. 32
8.1.3.6 KILL FAILURE . 33
8.1.3.7 LOAD QUERY . 33
8.1.3.8 LOAD QUERY COMPLETE . 33
8.1.3.9 LOAD QUERY FAILURE . 34
8.1.3.10 MESSAGE STATUS QUERY . 34
8.1.3.11 MESSAGE STATUS QUERY COMPLETE . 34
8.1.3.12 MESSAGE STATUS QUERY FAILURE . 35
8.1.3.13 SET-DRX . 35
8.1.3.14 SET-DRX COMPLETE . 36
8.1.3.15 SET-DRX FAILURE . 36
8.1.3.16 RESET . 36
8.1.3.17 RESET COMPLETE . 37
8.1.3.18 RESET FAILURE . 37
8.1.3.18a KEEP-ALIVE . 37
8.1.3.18b KEEP-ALIVE COMPLETE . 37
8.1.3.19 RESTART . 38
8.1.3.20 FAILURE . 38
8.1.3.21 ERROR INDICATION . 38
8.2 Information Element Definitions . 39
8.2.1 General . 39
8.2.2 Message Type . 40
8.2.3 Message Content . 41
8.2.4 Old Serial Number . 41
8.2.5 New Serial Number . 41
8.2.6 Cell List . 42
8.2.7 Category . 44
8.2.8 Repetition Period . 44
8.2.9 Number of Broadcasts Requested . 45
8.2.10 Number of Broadcasts Completed List . 45
8.2.11 Failure List . 46
8.2.12 Radio Resource Loading List. 47
8.2.13 Cause . 48
8.2.14 Data Coding Scheme . 49
8.2.15 Recovery Indication . 49
8.2.16 Message Identifier. 49
8.2.17 Emergency Indicator . 50
8.2.18 Warning Type . 50
8.2.19 Warning Security Information . 50
8.2.20 Channel Indicator . 50
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8.2.21 Number of Pages . 51
8.2.22 Schedule Period . 51
8.2.23 Number of Reserved Slots . 52
8.2.24 Broadcast Message Type . 52
8.2.25 Warning Period . 52
8.2.26 Length Indicator . 53
8.2.27 Keep Alive Repetition Period . 53
9 List of system parameters . 54
9.1 Timers in the CBC . 54
Annex A (informative): Change History . 55
History . 56

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Foreword
rd
This Technical Specification (TS) has been produced by the 3 Generation Partnership Project (3GPP).
The contents of the present document are subject to continuing work within the TSG and may change following formal
TSG approval. Should the TSG modify the contents of the present document, it will be re-released by the TSG with an
identifying change of release date and an increase in version number as follows:
Version x.y.z
where:
x the first digit:
1 presented to TSG for information;
2 presented to TSG for approval;
3 or greater indicates TSG approved document under change control.
y the second digit is incremented for all changes of substance, i.e. technical enhancements, corrections,
updates, etc.
z the third digit is incremented when editorial only changes have been incorporated in the document.
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1 Scope
The present document specifies the Cell Broadcast Service Protocol (CBSP) between the Cell Broadcast Centre (CBC)
and the Base Station Controller (BSC).
2 References
The following documents contain provisions which, through reference in this text, constitute provisions of the present
document.
• References are either specific (identified by date of publication, edition number, version number, etc.) or
non-specific.
• For a specific reference, subsequent revisions do not apply.
• For a non-specific reference, the latest version applies. In the case of a reference to a 3GPP document (including
a GSM document), a non-specific reference implicitly refers to the latest version of that document in the same
Release as the present document.
[1] 3GPP TS 23.041: "Technical realization of Cell Broadcast Service (CBS)".
[2] 3GPP TS 23.003: "Numbering, addressing and identification".
[3] 3GPP TS 44.012: "Short Message Service Cell Broadcast (SMSCB) support on the mobile radio
interface".
[4] 3GPP TS 23.038: "Alphabets and language-specific information".
[5] 3GPP TS 24.008: "Mobile radio interface Layer 3 specification; Core network protocols".
[6] IETF RFC 793 (September 1981): "Transmission Control Protocol".
[7] IETF RFC 2507 (February 1999): "IP header compression".
[8] IETF RFC 1990 (August 1996): "The PPP Multilink Protocol (MP)".
[9] IETF RFC 2686 (September 1996): "The Multi-Class Extension to Multi-Link PPP".
[10] IETF RFC 2509 (February 1999): "IP Header Compression over PPP".
[11] 3GPP TS 45.002: "Multiplexing and multiple access on the radio path".
[12] 3GPP TS 44.018: "Mobile radio interface layer 3 specification; Radio Resource Control Protocol".
[13] 3GPP TS 44.060: "General Packet Radio Service (GPRS); Mobile Station (MS) - Base Station
System (BSS) interface; Radio Link Control / Medium Access Control (RLC/MAC) protocol".
[14] 3GPP TS 23.002: "Network architecture".
3 Definitions and abbreviations
3.1 Definitions
For the purposes of the present document, the following terms and definitions apply:
CBS message: An information message broadcasted on the basic or extended cell broadcast channel (CBCH) in
unacknowledged mode to mobile stations located within the Cell Broadcast area. A CBS message may contain
information such as road traffic or weather information, originating from a Cell Broadcast Entity (CBE) communicating
with the CBC (see 3GPP TS 23.041 [1]).
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CBS message reference: Uniquely identifies a CBS message by the four elements: Message Identifier, Serial Number,
Cell Identifier and Channel Indicator.
Cell Broadcast area: An area comprising of one or more cells in which the CBS message or the emergency message is
broadcasted. A Cell Broadcast area is always contained within a BSC area (see 3GPP TS 23.002 [14]).
CBS message operational state: A cell in CBS message operational state is able to broadcast CBS messages.
Emergency message: A warning message conveying a small amount of data to indicate the imminent occurrence of an
emergency such as earthquake, tsunami etc. The emergency message is broadcasted to mobile stations in idle mode,
packet idle mode and dedicated mode (see 3GPP TS 44.018 [12]) and to mobile stations in packet transfer mode and
dual transfer mode (see 3GPP TS 44.060 [13]) located within the Cell Broadcast area.
Emergency message operational state: A cell in emergency message operational state is able to broadcast emergency
messages.
Emergency message reference: Uniquely identifies an emergency message by the three elements: Message Identifier,
Serial Number and Cell Identifier.
Elementary Procedure: CBSP consists of Elementary Procedures (EPs). An Elementary Procedure is a unit of
interactions between the CBC and the BSC. These EPs are defined separately and are intended to be used to build up
complete sequences in a flexible manner. If the independence between some EPs is restricted, it is described under the
relevant EP description. Unless otherwise stated by the restrictions, the EPs may be invoked independently of each
other as stand alone procedures, which can be active in parallel. Support of parallel procedures in the BSC is optional.
An EP consists of an initiating message and possibly a response message. Two kinds of EPs are used:
- Class 1: Elementary Procedures with response (success or failure).
- Class 2: Elementary Procedures without response.
For Class 1 EPs, the types of responses can be as follows:
Successful
- A signalling message explicitly indicates that the EP is successfully completed.
Unsuccessful
- A signalling message explicitly indicates that the EP failed.
- On time supervision expiry (i.e. absence of expected response).
Class 2 EPs are always considered as successful.
3.2 Abbreviations
For the purposes of the present document, the following abbreviations apply:
BSC Base Station Controller
CBC Cell Broadcast Centre
CBCH Cell Broadcast Channel
CBE Cell Broadcast Entity
CBS Cell Broadcast Service
CBSP Cell Broadcast Service Protocol
EP Elementary Procedure
ETWS Earthquake and Tsunami Warning System
MS Mobile Station
SMSCB Short Message Service Cell Broadcast
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4 General
4.1 Procedure Specification Principles
The principle for specifying the procedure logic is to specify the functional behaviour of the BSC exactly and
completely. The CBC functional behaviour is left unspecified.
The following specification principles have been applied for the procedure text in clause 7:
- The procedure text discriminates between:
1) Functionality which "shall" be executed:
- The procedure text indicates that the receiving node "shall" perform a certain function Y under a certain
condition. If the receiving node supports procedure X but cannot perform functionality Y requested in the
REQUEST message of a Class 1 EP, the receiving node shall respond with the message used to report
unsuccessful outcome for this procedure, containing an appropriate cause value.
2) Functionality which "shall, if supported" be executed:
- The procedure text indicates that the receiving node "shall, if supported," perform a certain function Y
under a certain condition. If the receiving node supports procedure X, but does not support functionality
Y, the receiving node shall proceed with the execution of the EP, possibly informing the requesting node
about the not supported functionality.
4.2 Specification Notations
For the purposes of the present document, the following notations apply:
Procedure When referring to an Elementary Procedure in the specification the procedure name is written with
the first letters in each word in upper case characters followed by the word "procedure", e.g.
Write-Replace procedure.
Message When referring to a message in the specification the MESSAGE NAME is written with all letters
in upper case characters followed by the word "message", e.g. WRITE-REPLACE message.
IE When referring to an information element (IE) in the specification the Information Element Name
is written with the first letters in each word in upper case characters and all letters in Italic font
followed by the abbreviation "IE", e.g. Old Serial Number IE.
Value of an IE When referring to the value of an information element (IE) in the specification the "Value" is
written as it is specified in subclause 8.2 enclosed by quotation marks, e.g. "Abstract Syntax Error
(Reject)" or "Background ".
5 Transport and Data Link layer
5.1 General
TCP over IP shall be supported as the transport for data streams on the BSC-CBC interface. The data link layer is as
specified in subclause 5.3.
During normal operation the CBC initiates all message transfer and query operations. The BSC responds to the message
transfer and query operations initiated by the CBC.
The BSC only initiates the message transfer in case an error (Failure Indication procedure) or recovery (Restart
Indication procedure) is to be reported.
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The node initiating the message transfer is also responsible for the establishment of the TCP connection, in case no TCP
connection already exist. An already established TCP connection may be used for message transfer.
The initiator of a connection is responsible for the termination of the TCP connection.
5.2 TCP /IP
The transport protocol used shall be TCP, which is specified in RFC 793 [6].
The transport bearer is identified by the TCP port number and the IP address (source TCP port number, destination TCP
port number, source IP address, destination IP address).
The TCP Destination Port number for CBSP messages is 48049/tcp. It is the registered port number for  3GPP Cell
Broadcast Service Protocol CBSP (3gpp-cbsp).
The 3gpp-cbsp destination port number 48049/tcp shall be used by both entities (BSC or CBC) whenever it sets up a
new TCP connection. When it sends CBSP messages on an existing TCP connection, the sending entity (BSC or CBC)
shall use as TCP destination port number either 48049/tcp if it was the initiator of this TCP connection, or the TCP
source port number that was received from the peer entity that had initiated this existing TCP connection.
An IP BSC/CBC-node shall support IPv4. The support of IPv6 is optional.
IP dual stack support is recommended for the potential transition period from IPv4 to IPv6 in the transport network.
5.3 Data Link layer
It is recommended that a BSC/CBC using IP transport implement the data link layer using Ethernet.
NOTE: This does not preclude the single implementation and use of any other data link layer protocol fulfilling
the GERAN requirements toward the upper layers.
A BSC/CBC using IP transport having interfaces connected via low bandwidth PPP links like E1/T1 shall also support
IP Header Compression [7] and the PPP extensions ML/MC-PPP [8], [9]. In this case the negotiation of header
compression [7] over PPP shall be performed according to [10].
6 Functions of CBSP
The CBSP has the following functions:
- Message Handling: This function is responsible for enabling the broadcast of new CBS and emergency
messages, replacing CBS and emergency messages currently being broadcasted and for terminating the
broadcast of specific CBS and emergency messages. This function may also be used to obtain the message status
of a specific CBS message.
- DRX Handling: This function is responsible for the configuration of the SMSCB DRX parameters.
- Load Handling: This function determines the load status of the broadcast channels at any particular point in time.
- Reset: This function terminates the broadcasting of all CBS and emergency messages in one or more cells.
- Error Handling: This function allows reporting of general error situations, for which function specific error
messages have not been defined.
- Supervision Handling: This function handles the supervision of the CBSP availability between the CBC and the
BSC.
These functions are implemented by one or several CBSP elementary procedures described in clause 7.
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7 CBSP Procedures
7.1 Elementary Procedures
In the following tables, all EPs are divided into Class 1 and Class 2 Procedures.
Table 7.1.1: Class 1 Procedures
Elementary Initiating Message Successful Outcome Unsuccessful Outcome
Procedure
Response message Response message
Write-Replace WRITE-REPLACE WRITE-REPLACE WRITE-REPLACE FAILURE
COMPLETE
Kill KILL KILL COMPLETE KILL FAILURE
Load Status Enquiry LOAD QUERY LOAD QUERY COMPLETE LOAD QUERY FAILURE
Message Status MESSAGE STATUS QUERY MESSAGE STATUS QUERY MESSAGE STATUS QUERY
Query COMPLETE FAILURE
Set DRX SET-DRX SET-DRX COMPLETE SET-DRX FAILURE
Reset RESET RESET COMPLETE RESET FAILURE
Keep Alive KEEP-ALIVE KEEP-ALIVE COMPLETE -

Table 7.1.2: Class 2 Procedures
Elementary Procedure Message
Restart Indication RESTART
Failure Indication FAILURE
Error Indication ERROR INDICATION

7.2 Write-Replace
7.2.1 General
The purpose of the Write-Replace procedure is to broadcast a new CBS message or emergency message or to replace an
ongoing CBS message or emergency message broadcast with a new CBS message or emergency message.
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7.2.2 Successful Operation
7.2.2.1 General
CBC
BSC
WRITE-REPLACE
WRITE-REPLACE
COMPLETE
Figure 7.2.2.1.1: Write-Replace Procedure: Successful Operation
The Write-Replace procedure is initiated by the CBC sending the WRITE-REPLACE message to the BSC (see
figure 7.2.2.1.1).
The WRITE-REPLACE message may be sent as a request to broadcast a new CBS message or emergency message
without replacing an ongoing CBS message or emergency message broadcast, or as a request to replace an ongoing
CBS message or emergency message broadcast with a new CBS message or emergency message. A WRITE-REPLACE
message shall not contain a simultaneous broadcast request of a CBS message and an emergency message.
Broadcast request of a CBS message is defined in subclause 7.2.2.2 while broadcast request of an emergency message is
defined in subclause 7.2.2.3.
7.2.2.2 Broadcast request of a CBS message
A CBS message is uniquely identified by the four elements Message Identifier IE, Cell Identifier field in the Cell List
IE, Serial Number field in the New Serial Number IE or in the Old Serial Number IE and the Channel Indicator IE.
If only the New Serial Number IE, and not the Old Serial Number IE, is included in the WRITE-REPLACE message,
then the BSC shall interpret the message as a write request, i.e. a broadcast request of a new CBS message without
replacing an ongoing CBS message broadcast. The new CBS message is identified by the four elements Message
Identifier IE, the twelve most significant bits of the New Serial Number IE, Cell Identifier field in the Cell List IE and
the Channel Indicator IE.
If both the New Serial Number IE and the Old Serial Number IE are present in the WRITE-REPLACE message, then
the BSC shall interpret the message as a replace request, i.e. a request to replace an ongoing CBS message broadcast
with a new CBS message. In this case the BSC shall start the Write-Replace procedure by terminating the ongoing CBS
message broadcast, as defined in subclause 7.3.2.2, before broadcasting the new CBS message. The replaced CBS
message is identified by the four elements Message Identifier IE, the twelve most significant bits of the Old Serial
Number IE, Cell Identifier field in the Cell List IE and the Channel Indicator IE.
If termination of the replaced CBS message fails in a cell, then the BSC shall not proceed with the broadcast of the new
CBS message for this particular cell. After completing the Write-Replace procedure in the remaining cells, the BSC
shall return the WRITE-REPLACE FAILURE message to the CBC, see subclause 7.2.3.
A CBS message may be broadcasted on one of two different cell broadcast channels, a basic channel or an extended
channel (see 3GPP TS 45.002 [11]), as indicated by the Channel Indicator IE.
The BSC initiates broadcasting of the CBS message within the Cell Broadcast area, i.e. in the cell(s) as indicated by the
Cell Identifier field in the Cell List IE.
The BSC shall broadcast the CBS message according to the value of the Number of Broadcasts Requested IE and the
Repetition Period IE. If the value of Number of Broadcasts Requested IE is set to "0", the BSC shall broadcast the CBS
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message until the CBC requests otherwise. If the value is different from "0", the BSC shall broadcast the CBS message
as many times as indicated in the Number of Broadcasts Requested IE.
The Repetition Period IE indicates the periodicity of which the CBS message is to be broadcasted.
In the event of a conflict where the BSC has more than one CBS message to send at the same time, the BSC shall decide
the order of such CBS messages as an implementation matter.
The BSC shall accept the broadcast request of a CBS message according to the value of the Category IE as follows:
- If the value of Category IE is indicated as 'High Priority', then the BSC shall accept the broadcast request if
message slots according to the Repetition Period IE are available on the broadcast channel following the
scheduling of already accepted high and/or normal priority CBS messages.
The first broadcast of a high priority CBS message is performed at the earliest opportunity and the subsequent
broadcasts according to the Repetition Period IE.
- If the value of Category IE is indicated as 'Normal', then the BSC shall accept the broadcast request if message
slots according to the Repetition Period IE are available on the broadcast channel following the scheduling of
already accepted high and/or normal priority CBS messages.
The broadcast of a normal priority CBS message is always performed according to the Repetition Period IE.
- If the value of Category IE is indicated as 'Background', then the BSC shall accept the broadcast request if
message slots according to the Repetition Period IE are available on the broadcast channel following the
scheduling of high and/or normal priority CBS messages and/or already accepted background CBS messages.
The broadcast of a background CBS message is performed according to the Repetition Period IE.
NOTE: The repetition frequency of an ongoing CBS message broadcast of type "Background" may be reduced if
a CBS message broadcast request of type "Normal" or "High Priority" is received in the BSC for the same
cell. If message slots on the particular broadcast channel become available again, the requested repetition
period of the background CBS message shall be resumed.
Number of Pages IE indicates the total number of pages included in the CBS message, i.e. the number of Message
Content IE"s included in the WRITE-REPLACE message. The BSC shall pass the Data Coding Scheme IE and
Message Content IE transparently to the radio interface protocol.
If the Write-Replace procedure is successful in all cells as indicated in the Cell List IE, the BSC shall return the
WRITE-REPLACE COMPLETE message to the CBC as described in subclause 7.2.2.4.
If the Write-Replace procedure fails in at least one cell, the BSC shall respond to the CBC by sending the WRITE-
REPLACE FAILURE message, see subclause 7.2.3.
After completion of the broadcast according to the associated Number of Broadcasts Requested IE and the Repetition
Period IE, the BSC shall remove any referenc
...