Intelligent transport systems — Communication access for land mobiles (CALM) — Non-IP networking — Part 2: Legacy system support

ISO 29281-2:2013 specifies elements of communications for cooperative ITS which are not based on the Internet protocol. The following architectures, procedures and protocols are specified: -Support of communication interfaces (DSRC-CI) using ISO 15628; -Support of ISO 15628 DSRC applications via an ITS ad-hoc access technology.

Systèmes intelligents de transport — Accès aux communications des services mobiles terrestres (CALM) — Réseautique non-IP — Partie 2: Support pour systèmes hérités

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Status
Withdrawn
Publication Date
10-Apr-2013
Withdrawal Date
10-Apr-2013
Current Stage
9599 - Withdrawal of International Standard
Completion Date
30-Jan-2019
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INTERNATIONAL ISO
STANDARD 29281-2
First edition
2013-04-15
Intelligent transport systems —
Communication access for land mobiles
(CALM) — Non-IP networking —
Part 2:
Legacy system support
Systèmes intelligents de transport — Accès aux communications des
services mobiles terrestres (CALM) — Réseautique non-IP —
Partie 2: Support pour systèmes hérités
Reference number
ISO 29281-2:2013(E)
©
ISO 2013

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ISO 29281-2:2013(E)

COPYRIGHT PROTECTED DOCUMENT
© ISO 2013
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form
or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior
written permission. Permission can be requested from either ISO at the address below or ISO’s member body in the country of
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Published in Switzerland
ii © ISO 2013 – All rights reserved

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ISO 29281-2:2013(E)

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Requirements . 2
4 Architecture . 2
4.1 ITS station . 2
4.2 Communication scenarios . 2
4.3 Implementation scenarios . 2
4.4 Legacy CIs . 3
4.5 15628 applications . 5
5 Facilities layer protocols . 5
5.1 General . 5
5.2 Groupcast registration handler . 6
5.3 Repetitive packet transmission handler . 6
5.4 Legacy CI Port Agent . 6
5.5 15628 kernel emulator . 6
5.6 Basic primitive application functions . 8
6 Conformance . 8
7 Test methods . 8
Annex A (normative) ASN.1 . 9
Annex B (normative) 15628 legacy CI .10
Annex C (informative) 15628 legacy service guidelines .15
Bibliography .24
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ISO 29281-2:2013(E)

Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2. www.iso.org/directives
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received. www.iso.org/patents
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
The committee responsible for this document is ISO/TC 204, Intelligent transport systems.
This first edition of ISO 29281-2, together with ISO 29281-1, cancels and replaces ISO 29281:2011.
ISO 29281 consists of the following parts, under the general title Intelligent transport systems —
Communication access for land mobiles (CALM) — Non-IP networking:
— Part 1: Fast networking & transport layer protocol (FNTP)
— Part 2: Legacy system support
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ISO 29281-2:2013(E)

Introduction
This part of ISO 29281 is part of a family of International Standards for communications access for land
mobiles (CALM). An introduction to the whole set of International Standards is provided in ISO 21217.
This part of ISO 29281 is the second part of a multi-part series which determines intelligent transport
systems (ITS) communication functionalities which are different to functionalities from the set of
Internet protocols.
These functionalities are protocols and procedures located in the various layers and entities of the ITS
station.
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INTERNATIONAL STANDARD ISO 29281-2:2013(E)
Intelligent transport systems — Communication access for
land mobiles (CALM) — Non-IP networking —
Part 2:
Legacy system support
1 Scope
This part of ISO 29281 specifies elements of communications for cooperative ITS which are not based
on the Internet protocol.
The following architectures, procedures and protocols are specified:
— Support of communication interfaces (DSRC-CI) using ISO 15628;
— Support of ISO 15628 DSRC applications via an ITS ad-hoc access technology.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated
references, only the edition cited applies. For undated references, the latest edition of the referenced
document (including any amendments) applies.
ISO/IEC 8825-2, Information technology — ASN.1 encoding rules: Specification of Packed Encoding Rules (PER)
ISO 15628, Intelligent transport systems — Dedicated short range communication (DSRC) — DSRC
application layer
ISO 21217, Intelligent transport systems — Communications access for land mobiles (CALM) — Architecture
ISO 21218, Intelligent transport systems — Communications access for land mobiles (CALM) — Access
technology support
ISO 24102-1, Intelligent transport systems — Communications access for land mobiles (CALM) — ITS station
management — Part 1: Local management
ISO 24102-3, Intelligent transport systems — Communications access for land mobiles (CALM) — ITS station
management — Part 3: Service access points
ISO 24102-4, Intelligent transport systems — Communications access for land mobiles (CALM) — ITS station
management — Part 4: Station-internal management communications.
ISO 24102-5, Intelligent transport systems — Communications access for land mobiles (CALM) — ITS station
management — Part 5: Fast service advertisement protocol (FSAP)
ISO 24103, Intelligent transport systems — Communications access for land mobiles (CALM) — Media
adapted interface layer (MAIL)
ISO 29281-1, Intelligent transport systems — Communication access for land mobiles (CALM) — Non-IP
networking — Part 1: Fast networking & transport layer protocol (FNTP)
ETSI TS 102 985-1, Intelligent transport systems (ITS) — Communications Access for Land Mobiles (CALM) —
Test specifications for non-IP networking (ISO 29281) — Part 1: Protocol implementation conformance
“statement (PICS) proforma
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ISO 29281-2:2013(E)

ETSI TS 102 985-2, Intelligent transport systems (ITS) — Communications Access for Land Mobiles
(CALM) — Test specifications for non-IP networking (ISO 29281) — Part 2: Test suite structure & test
purposes (TSS&TP)
ETSI TS 102 985-3, Intelligent transport systems (ITS) — Communications Access for Land Mobiles
(CALM) — Test specifications for non-IP networking (ISO 29281) — Part 3: Abstract test suite and partial
PIXIT (ATS) specification
3 Requirements
Communication functionality, which is different to the functionality out of the set of Internet protocols
(IP), is referred to as non-IP functionality in this multi-part series.
The functionality to support legacy systems, especially those related to ISO 15628 “DSRC application
layer” shall be as specified in this part of ISO 29281.
Detailed requirements are specified in the following clauses of this part of ISO 29281:
— Clause 4 specifies architectural elements;
— Clause 5 specifies facility layer protocols;
— Clause 6 specifies conformance declaration;
— Clause 7 specifies test methods;
— Annexes A and B provide further mandatory requirements;
— The informative Annex C provides 15628 legacy service guidelines.
4 Architecture
4.1 ITS station
The specifications given in this part of ISO 29281 shall comply with the ITS station architecture and with
the concept of an ITS station communication unit (ITS-SCU) as specified in ISO 21217 and ISO 24102-4.
4.2 Communication scenarios
Communication scenarios are specified in ISO 24102-1 and in ISO 21217.
4.3 Implementation scenarios
The protocols specified in this part of ISO 29281 may support the implementation architectures
introduced in ISO 21217 and illustrated in Figures 1 and 2 with an ITS station and a peer DSRC station.
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ISO 29281-2:2013(E)

Combined ITS-S router / host
Applications
Facilities layer
Networking & transport
layer (FNTP)
Access layer
(wireless CIs)
Link to peer station
Figure 1 — Combined ITS-S host/router
ITS-S host
Applications
ITS-S router
Facilities layer
Networking & transport Networking & transport
layer layer
Access layer (LAN CI) LAN CI Wireless CIs
ITS station-internal network
Link to peer station
Figure 2 — ITS-S host and ITS-S router separated in different ITS-SCUs
4.4 Legacy CIs
An existing ITS-S access layer technology may be implemented in an ITS station as a “Legacy CI”, as
presented in Figure 3, such that it can communicate with peer stations that are not necessarily aware
of any ITS-S context, and where none of the networking protocols specified for ITS-S are used in the
wireless link.
Types of CIs are specified in ISO 21218 in I-parameter 22 “Medium”. The only legacy CI medium identified
so far in ISO 21218 is “DSRC” with an application layer specified in ISO 15628. Further types may be added.
© ISO 2013 – All rights reserved 3
Management
Management
Security
Management
Security

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ISO 29281-2:2013(E)

ITS-S applications
Legacy Service Entity
FA
ITS-S facilities layer
Legacy CI Port Agent
NF
ITS-S networking & transport layer
FNTP
IN
ITS-S access layer
Extended CAL
Legacy CI
Figure 3 — Legacy CI
Inside the ITS station, the Fast networking & transport layer protocol (FNTP) specified in ISO 29281-1
shall be used for the forwarding of packets between the ITS-S access layer and the ITS-S facilities layer.
This requires:
— implementing a CALM adaptation layer (CAL) as specified in ISO 21218, extended with the additional
functionality for FNTP support as specified in this part of ISO 29281, which optionally may also
include parts of the service processing functionality;
— making use of the “Legacy CI Port Agent” as specified in this part of ISO 29281 and in ISO 24102-1.
Legacy CIs shall specify the medium specific parameters presented in Table 1 (see ISO 21218 for the I-
parameter 254 “MediumParameter”).
Table 1 — Legacy CI parameters
MediumParam.mediumPar.no MediumParam.detail Description
0 LegacyOption Optional classification of different options of the
same legacy CI.
1 PortPA Port number of the “Legacy CI Port Agent” con-
necting to the applicable “Legacy Service Entity”.
The “Legacy Service Entity” shall register at the “Legacy CI Port Agent” indicating the CI class and legacy
option of the required legacy CI.
Further details depend on the existing communication interface technology. Normative examples for
legacy systems compliant with ISO 15628 are provided in Annex B.
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ISO 29281-2:2013(E)

4.5 15628 applications
Applications built on top of the DSRC application layer as specified in ISO 15628 may be operated over
an ITS CI of CI class CIC-wl1 specified in ISO 21218. The services shall interface with the FNTP via the
“15628 Kernel Emulator”, see Figure 4.
NOTE In the given context, 15628 applications are also referred to as 15628 legacy applications.
CALM 15628 FAST ITS service user entity
ITS-S applications
15628 legacy application
FA
ITS-S facilities layer
15628 Kernel Emulator
NF
ITS-S networking & transport layer
FAST
IN
ITS-S access layer
CALM CI
of CI class CIC-wl1
Figure 4 — 15628 legacy service
The 15628 initialization phase shall be implemented with the groupcast functionality specified in
ISO 24102-1 and in ISO 24102-5.
The “15628 Kernel Emulator” shall perform the following tasks:
— Register at server groupcast manager for periodic transmission of BST, if applicable;
— Register at client groupcast manager for transmission of VST, if applicable;
— Emulate the 15628 T-Kernel interface for usage by applications;
— Map the 15628 “FlowControl” on BC-VCI and UC-VCI.
The purpose of 15628 LID shall be served by Link-ID specified in ISO 21218.
Detailed procedures are specified in Clause 5.
5 Facilities layer protocols
5.1 General
The ITS-S facilities layer comprises the OSI layers five, six and seven as specified in ISO 21217.
The ITS-S facilities layer shall use the service primitives provided by the ITS management entity in the
MF-SAP for management purposes as specified in ISO 24102-3.
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ISO 29281-2:2013(E)

The ITS-S facilities layer shall be connected to services via an API. Details of the API are outside the
scope of this part of ISO 29281.
The ITS-S facilities layer shall use the services provided in the NF-SAP by the ITS-S networking &
transport layer.
5.2 Groupcast registration handler
The groupcast registration handler shall be as specified in ISO 24102-5.
5.3 Repetitive packet transmission handler
The ITS-S facilities layer shall be responsible for repetitive transmission of data packets, as requested
by the service.
5.4 Legacy CI Port Agent
Upon registration of a legacy CI at the ITS station management entity as specified in ISO 24102-1, the
ITS station management entity notifies the “Legacy CI Port Agent” about the presence of this legacy CI,
indicating the Link-ID and the type of legacy CI as specified in ISO 21218.
The “Legacy CI Port Agent” shall:
— use the NF-SAP service NF-FNTP-PORT of the FNTP to get a host port number from the port number
manager assigned as specified in ISO 29281-1;
— notify the port number to the ITS station management entity, indicating also the Link-ID of the
related legacy CI.
The “Legacy CI Port Agent” shall maintain a separate host port number for each legacy CI registered in
the ITS station.
Details on ISO 15628 legacy CIs are provided in B.1.
5.5 15628 kernel emulator
5.5.1 15628 legacy applications
15628 legacy applications “option 3” shall be treated in the same way as ITS-S applications designed
for the FNTP.
NOTE The functionality of ACn commands specified in EN 12795:2003 is not supported.
5.5.2 CI classes
The 15628 kernel emulator enables ITS applications built on ISO 15628 to be operated over a CALM
wireless CI of CI class CIC-wl1 specified in ISO 21218, based on the FNTP. Usage of CIs of CI class CIC-wl5
specified in ISO 21218 shall be prohibited.
5.5.3 Registration of 15628 applications
In a server station the 15628 kernel emulator shall register available 15628 applications at the
groupcast manager using MF-REQUEST 1 “GCregServer” specified in ISO 24102-5 with parameters as
specified in Table 2.
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ISO 29281-2:2013(E)

Table 2 — Registration of 15628 server application at groupcast manager
Parameter Name Value
GCregServer.applicationID As specified in ISO 24102-1
GCregServer.gCschedule As specified in ISO 24102-5
GCregServer.priority As specified in ISO 24102-5
GCregServer.serviceDataReg As specified in ISO 24102-5
ServiceDataReg.nonipData.serviceID “aid” as contained in “ApplicationList” specified in ISO 15628
ServiceDataReg.nonipData.timeout defined by implementation
ServiceDataReg.nonipData.Data not present
ServiceDataReg.nonipData.Port Port number as specified in ISO 29281-1
The purpose of “BeaconID” specified in ISO 15628 shall be given by the “serverID” contained in “SAM”
specified in ISO 24102-5.
In a client station the 15628 kernel emulator shall register available 15628 applications at the groupcast
manager using MF-REQUEST 4 “GCregClient” with parameters as specified in Table 3.
Table 3 — Registration of 15628 server application at groupcast manager
Parameter Name Value
GCregClient.applicationID As specified in ISO 24102-1
GCregClient.priority As specified in ISO 24102-5
GCregClient.serviceID “aid” as contained in “ApplicationList” specified in ISO 15628
GCregClient.contextData “eid” and “parameter” as contained in “ApplicationList” and
“obeConfiguration” as contained in “VST”; “eid”, “parameter”
and “VST” as specified in ISO 15628.
5.5.4 Service operation phase
In the service operation phase the PDUs of the 15628 services GET, SET, ACTION and EVENT-REPORT as
specified in ISO 15628 shall be exchanged.
For the purpose of this part of ISO 29281, the ITS-FPDU contained in an FNTP NPDU as specified in
ISO 29281-1 shall contain the T-APDU as specified in ISO 15628.
The “15628 Kernel Emulator” shall support concatenation and chaining as specified in ISO 15628.
The “FMT-ID” element shall be as specified in Table 4.
Table 4 — Selection of “messageType”
15628 service primitive 15628 parameter FMT-ID
“mode”
SET.request, ACTION.request, EVENT-REPORT.request 0 5
GET.request - 6
SET.request, ACTION.request, EVENT-REPORT.request 1 6
GET.response, SET.response, ACTION.response, EVENT-REPORT. - 7
response
The 15628 parameters “FlowControl” and “LID” are not supported explicitly. “FlowControl” and “LID”
shall be considered in the operation phase as specified in Table 5.
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ISO 29281-2:2013(E)

Table 5 — 15628 “FlowControl” and “LID”
15628 CALM
FlowControl LID Mode Purpose FMT-ID VCI
1 broadcast 0 Broadcast transmission 5 TX via BC-VCI
1, 4 private 0 Data transmission 5 TX via UC-VCI
7 private 1 Data exchange - Request 6 TX via UC-VCI
10 private - Data exchange - Response 7 TX via UC-VCI
2, 3, 5, 6, 8, 9, - - - - -
11
The purpose of 15628 “LID” shall be served by Link-ID.
5.6 Basic primitive application functions
Basic primitive application functions are an essential element of legacy CIs according to option 2
specified in Annex B. They are related to on-board unit’s resources such as human-machine interface,
IC card interface and so on. Each basic primitive application function is uniquely addressed by a port
number. A roadside station selects and combines basic primitive application functions, see Figure B.2, in
order to realize a specific service.
Examples of the basic primitive application functions are shown in Annex C.
NOTE Basic primitive application functions are executed on LPP.
6 Conformance
The “Protocol Implementation Conformance Statements” (PICS) proforma is specified in ETSI TS 102 985-1.
7 Test methods
The “Test Suite Structure & Test Purposes” (TSS&TP) for conformance testing are specified in
ETSI TS 102 985-2.
The “Abstract Test Suite” (ATS) for conformance testing is specified in ETSI TS 102 985-3.
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ISO 29281-2:2013(E)

Annex A
(normative)

ASN.1
A.1 Use of modules
The following ASN.1 module is specified in this Annex:
— CALMlegacySupport { iso (1) standard (0) calm-nonip(29281) legacy (2) version1 (1)}
A.2 Module CALMnonip
This module specifies ASN.1 type definitions together with useful ASN.1 value definitions.
It imports ASN.1 definitions from a module specified in ISO 29281-1.
Unaligned packed encoding rules (PER) as specified in ISO/IEC 8825-2 shall be applied for this ASN.1 module.
In order to achieve octet alignment enabling cheap implementations, “fill” bits were defined. All fill bits
shall be set to the value ‘0’b.
CALMlegacySupport { iso (1) standard (0) calm-nonip(29281) legacy (2) version1 (1)}

DEFINITIONS AUTOMATIC TAGS::=BEGIN

IMPORTS

PortNumber FROM CALMfntp { iso (1) standard (0) calm-nonip(29281) fntp(1) version1 (1)}

;

-- End of IMPORTS

-- General types --

Param15628::=SEQUENCE{
     fill     BIT STRING (SIZE(7)),
   params   CHOICE{
         legacyOption   INTEGER(0.255),
     portPA     PortNumber -- Port number of 15628 Port
Manager
     }
}

FNTPlpp::=OCTET STRING (SIZE(0.65535))

-- Values

-- Dummy values not defined here which cannot be imported. To be replaced by proper type.

/*
    The ASN.1 specification has been checked for conformance to the ASN.1
    standards by OSS ASN.1 Syntax Checker, and by OSS ASN-1STEP
*/

END
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ISO 29281-2:2013(E)

Annex B
(normative)

15628 legacy CI
B.1 15628 legacy CIs
This Annex presents normative details for legacy CIs being compliant with ISO 15628.
Two options of handling 15628 legacy CIs are specified. Distinction is made by the way in which the
15628 services are implemented.
Option 1: Restricted to CI class CIC-wl5 specified in ISO 21218. Adaptation to CALM performed
by means of a “15628 Agent Application” below the IN-SAP being responsible for the quick parts of the
service, a “15628 Principal Application” above the NF-SAP being responsible for the slow parts of the
service and for global control of the service, and the “15628 Port Manager”, see Figures 3 and B.1.
Option 2: Restricted to CI class CIC-wl5 specified in ISO 21218. Adaptation to CALM performed
by means of the LPCP below the IN-SAP, the FNTP extension LPP, and the “15628 Port Manager”, see
Figures 3 and B.2.
The “Agent Application” and the LPCP shall provide the functionality of the CALM adaptation layer (CAL)
specified in ISO 21218.
The purpose of LID specified in ISO 15628 shall be achieved by means of the CI-ID of a UC-VCI.
B.2 Option 1
Figure B.1 shows the architecture for option 1. Two communication entities are distinguished in
Figure B.1:
a) 15628 FAST ITS service provider entity (communication master) typically implemented as 15628
DSRC roadside unit (RSU), and not being aware of CALM;
b) CALM 15628 FAST ITS service user entity (communication slave) with a functionality normally
available in a 15628 DSRC on-board unit (OBU), implemented in a CALM mobile unit.
NOTE 1 The communication master may also be implemented as presented for the communication slave.
NOTE 2 The term “DSRC” used above does not refer to IEEE DSRC, but to ISO 15623.
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ISO 29281-2:2013(E)

CALM 15628 FAST ITS service user entity
ITS-S applications
15628 Principal
Application
FA
ITS-S facilities layer
Legacy CI Port Agent
NF
ITS-S networking & transport layer
FAST
15628 FAST ITS service provider entity
IN
ITS-S access layer
CAL - Agent Application 15628 Application
Application Interface
Application Interface
APDU
CM – ISO 15628 ISO 15628
CM – OSI layer 2 OSI layer 2
CM – OSI layer 1 OSI layer 1
PSDU
Figure B.1 — CALM 15628 architecture with “Agent Application”
The complete 15628 legacy ITS service is arranged in an “Agent Application” and a “15628 Principal
Application”. The “Agent Application” shall autonomously handle time-critical packets received via the
“Application Interface”, i.e. packets received from the FAST ITS service provider application in the RSU.
Other packets may be forwarded to the “15628 Principal Application” without execution by the “Agent
Application”, e.g. packets addressed to the HMI interface or to an OBU component.
The 15628 FAST ITS service user entity contains a CALM 15628 communication module (CM), the
“Application Interface”, the CALM adaptation layer (CAL) contained in the “Agent Application”, the
“Legacy CI Port Agent” interfacing to the MF-SAP, the NF-SAP and to the API, and the “CALM 15628
Principal Application”.
The “Agent Application” shall interface the communication stack of the CM compliant with ISO 15628 via
the “Application Interface”. Examples of an “Application Interface” are given in [1, 2].
The “Agent Application” shall interface the ITS-S networking & transport layer via the IN-SAP, providing
the functionality of the CALM adaptation layer (CAL) specified in ISO 21218. The networking protocol
used to connect the “Agent Application” to the “15628 Port Manager” shall be FAST. The value of
“PortNumber” selecting the “Legacy CI Port Agent” shall be assigned by the ITS station management
entity upon activation of the “CALM 15628 CI”.
In case service data units (SDUs) are simultaneously received via the “Application Interface” and via the
IN-SAP, priority shall be given to the SDUs received via the “Application Interface”.
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ISO 29281-2:2013(E)

The CALM 15628 CI shall provide an MI-SAP compliant with ISO 24102-3 and ISO 21218 with restrictions
and amendments as specified in this part of ISO 29281. The CALM 15628 CI shall be of CI class “CIC-wl5”
and of CI access class “CIAC-1” according to
...

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