IEC 61162-401:2001

INTERNATIONAL IEC
STANDARD
61162-401
First edition
2001-11
Maritime navigation and radiocommunication
equipment and systems –
Digital interfaces –
Part 401:
Multiple talkers and multiple listeners –
Ship systems interconnection –
Application profile
Reference number
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INTERNATIONAL IEC
STANDARD
61162-401
First edition
2001-11
Maritime navigation and radiocommunication
equipment and systems –
Digital interfaces –
Part 401:
Multiple talkers and multiple listeners –
Ship systems interconnection –
Application profile
 IEC 2001  Copyright - all rights reserved
No part of this publication may be reproduced or utilized in any form or by any means, electronic or
mechanical, including photocopying and microfilm, without permission in writing from the publisher.
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Commission Electrotechnique Internationale
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International Electrotechnical Commission
For price, see current catalogue

– 2 – 61162-401  IEC:2001(E)
CONTENTS
FOREWORD.7
INTRODUCTION.9
1 Scope.9
1.1 General .9
1.2 Application profile.9
2 Normative references .9
3 Definitions .10
3.1 Terms.10
3.2 Abbreviations .13
3.3 Conventions .13
3.4 Protocol data types .15
3.5 Non-protocol types .17
3.6 Literals .18
4 Dependence on T-profile .18
4.1 General .18
4.2 LNA-LNA or MAU-LNA communication .18
4.3 Services required .18
4.4 Services required, but not used by the A-profile .19
4.5 Variable quality of service attributes .19
4.5.1 Reliability and safety .19
4.5.2 Real time response.19
4.5.3 Support for stream data .20
4.5.4 Maximum and minimum message lengths .20
4.6 Congestion and flow control .20
5 Functional requirements for MAU .20
5.1 General overview .20
5.2 MAU configuration management.21
5.2.1 Define MAU parameters (MauInitialize) .22
5.2.2 Connection open request (MauOpen) .23
5.2.3 Connection close (MauClose) .23
5.2.4 MAU state change call-back (MauState) .24
5.3 Session management, authentication and congestion control .25
5.3.1 Session control and authentication .25
5.3.2 Congestion control (MauSession).26
5.3.3 Request and connection limiting .26
5.4 Interface and connection point overview.26
5.4.1 Special considerations for anonymous broadcast (ABC) .27
5.4.2 MCP membership in interfaces .27
5.4.3 MCP attributes.27
5.4.4 Modify MCP attributes (McpGet, McpSet) .28
5.4.5 Interface attributes .29
5.4.6 Modify interface attributes (IfGet, IfSet) .29

61162-401  IEC:2001(E) – 3 –
5.5 Interface management.30
5.5.1 Define interface (IfTable) .31
5.5.2 Remove interface (IfRemove).31
5.5.3 Establish interface connection (IfOpen) .32
5.5.4 Close interface (IfClose) .32
5.5.5 Interface state change call-back (InterfaceState) .33
5.6 MCP transactions. .34
5.6.1 Function type transactions.35
5.6.2 Non-acknowledged write transactions.36
5.6.3 Subscribe type transactions.36
5.6.4 Individual subscribe transactions .37
5.6.5 Client side initiation (TransActivate) .38
5.6.6 Transaction cancellation (TransCancel).38
5.6.7 Client side transaction state change (TransClientState) .39
5.6.8 Server side transaction state change (TransServerState).39
5.7 Bulk data transfer .40
6 Functional requirements for LNAs.40
6.1 Context diagram and functional overview .40
6.2 MAU name management (MauAck, MauRequest, SessionClose).41
6.2.1 Duplicate MAU names .43
6.2.2 Local MAU names .43
6.2.3 Remote MAU names.43
6.3 LNA-LNA session management .45
6.3.1 Heard about LNA.45
6.3.2 Known LNA .45
6.3.3 Dead LNA.46
6.3.4 The LNA watchdog function .46
6.4 Local MAU connection management.47
6.4.1 MAU identification .47
6.4.2 Local MAU states .47
6.4.3 Starting MAU management .48
6.4.4 Ending MAU management .48
6.5 MAU control MCP.49
6.5.1 General overview.49
6.5.2 Functionality.49
6.5.3 Watchdog service .49
6.6 Session management .50
6.6.1 General principles .50
6.6.2 MAU session information .50
6.6.3 Session codes used for authentication.50
6.7 Accept type interface management.51
6.7.1 General overview.51
6.7.2 Possible errors in interface definitions or connection requests .51
6.7.3 Special handling of anonymous broadcast interfaces.52
6.7.4 Definition and removal of accept interface .53
6.7.5 Establishing and closing connections to accept interfaces .53
6.8 Connect type interface management .55

– 4 – 61162-401  IEC:2001(E)
6.9 General transaction management .57
6.9.1 MCP identity and transaction address.57
6.9.2 Transaction identity .57
6.9.3 Session identity .57
6.9.4 Transaction types .57
6.9.5 Exception handling .58
6.10 Accept side transaction management .59
6.10.1 Read, write and function transaction handling.61
6.10.2 Non-acknowledged write request .61
6.10.3 Initial subscribe .61
6.10.4 Initial individual subscribe.62
6.10.5 Server initiated subscribe acknowledgement .62
6.10.6 Server initiated individual subscribe acknowledgement.62
6.10.7 Anonymous broadcast subscribe .62
6.10.8 Cancellation of a transaction .62
6.11 Connect side transaction management .63
6.12 LNA-MAU .64
6.13 Use of priority levels in LNA .64
6.14 Congestion control .65
6.14.1 Congestion cases .65
6.14.2 LNA requirements.65
6.14.3 MAU requirements.66
7 Protocol defined as sequence diagrams .66
7.1 General conventions.66
7.1.1 Broken connections .66
7.1.2 Exception handling .66
7.2 LNA management.67
7.2.1 Opening LNA-LNA connection .67
7.2.2 LNA watchdog functionality.67
7.2.3 Congestion control.67
7.3 Opening and closing MAU sessions.68
7.3.1 MAU to MAU communication via same LNA.68
7.3.2 Opening a MAU session .68
7.3.3 Closing a MAU session.69
7.3.4 Finding a remote MAU in LNA.70
7.3.5 Server MAU or LNA dies.71
7.4 Opening and closing interfaces.71
7.4.1 Opening accept interface.71
7.4.2 Closing accept IF.72
7.4.3 Opening connect IF .72
7.4.4 Closing connect interface .73
7.5 Data transfer messages.73
7.5.1 Data transfer of read, write or function type .74
7.5.2 Subscribe data transfers.75
7.5.3 Data transfer cancel and transfer timeout .76

61162-401  IEC:2001(E) – 5 –
8 Message definitions.78
8.1 Introduction .78
8.1.1 Common message format .78
8.2 MAU-LNA messages .79
8.2.1 Message format.79
8.2.2 MAU session control.80
8.2.3 Interface definition messages .82
8.2.4 Data transfer messages.86
8.3 LNA-LNA message formats for reliable link.89
8.3.1 General message format .89
8.3.2 Connection management .89
8.3.3 MAU management .90
8.3.4 Interface connection management .92
8.3.5 Data transfer management .94
8.4 LNA-LNA message formats for multicast link .95
8.4.1 General message format .95
8.4.2 Different multi-cast ports .95
8.4.3 Name look-up and watchdog messages .96
8.4.4 Data transfer messages.98
8.4.5 Anonymous broadcast message details .99
9 General identity codes.100
9.1 Protocol and software version codes .100
9.2 Network address, node number and LNA id (address_m, word32_m).100
9.3 MAU identity (mauname_m, mauid_m) .100
9.4 Data object and MCP identity (mcid_m).101
9.5 Interface code (mcid_m).102
9.6 Data object name (mcname_m, mciname_m).102
9.7 Interface name (ifname_m) .102
9.8 Session identity (word16_m) .102
9.9 Transaction identity (word32_m) .102
9.10 Format string.102
9.10.1 Data record format encoding .102
9.10.2 Transaction type coding.104
9.10.3 Complete format string .104
9.11 Password (password_m) .104
10 Data marshalling .104
10.1 Introduction .104
10.2 Network octet order .105
10.2.1 General .105
10.2.2 Basic types.105
10.2.3 Composite types.106
10.2.4 Messages .106
10.3 Pack and unpack routines .106
10.3.1 Introduction .106
10.3.2 Pack routine .106
10.3.3 Unpack routine .107

– 6 – 61162-401  IEC:2001(E)
11 Communication link between MAU and LNA .107
11.1 Introduction .107
11.1.1 General service specification.107
11.1.2 Point to point .108
11.1.3 Connection oriented .108
11.1.4 Symmetrical and full duplex .108
11.1.5 Message based .108
11.1.6 Priority .108
11.1.7 Buffering and flow control .108
11.1.8 Reliable transfer .108
11.1.9 Error reporting .108
12 General principles for module functionality .109
12.1 Flexibility in receiving, conservatism in sending.109
12.2 Garbled messages .109
12.3 Closed communication links .109
Annex A (normative) Message codes .110
Annex B (normative) Error codes and message field values .112
Annex C (normative) Symbolic constants .113
Annex D (informative) Compatibility between MiTS and the IEC 61162-400 series.115

61162-401  IEC:2001(E) – 7 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
___________
MARITIME NAVIGATION AND RADIOCOMMUNICATION
EQUIPMENT AND SYSTEMS –
DIGITAL INTERFACES –
Part 401: Multiple talkers and multiple listeners –
Ship systems interconnection – Application profile
FOREWORD
1) The IEC (International Electrotechnical Commission) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of the IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To this
end and in addition to other activities, the IEC publishes International Standards. Their preparation is entrusted to
technical committees; any IEC National Committee interested in the subject dealt with may participate in this
preparatory work. International, governmental and non-governmental organizations liaising with the IEC also
participate in this preparation. The IEC collaborates closely with the International Organization for Standardization
(ISO) in accordance with conditions determined by agreement between the two organizations.
2) The formal decisions or agreements of the IEC on technical matters express, as nearly as possible, an
international consensus of opinion on the relevant subjects since each technical committee has representation from
all interested National Committees.
3) The documents produced have the form of recommendations for international use and are published in the form
of standards, technical specifications, technical reports or guides and they are accepted by the National
Committees in that sense.
4) In order to promote international unification, IEC National Committees undertake to apply IEC International
Standards transparently to the maximum extent possible in their national and regional standards. Any divergence
between the IEC Standard and the corresponding national or regional standard shall be clearly indicated in the
latter.
5) The IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with one of its standards.
6) Attention is drawn to the possibility that some of the elements of this International Standard may be the subject
of patent rights. The IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 61162-401 has been prepared by IEC technical committee 80:
Maritime navigation and radiocommunication equipment and systems.
The text of this standard is based on the following documents:
FDIS Report on voting
80/310/FDIS 80/325/RVD
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 3.
The special typographical conventions and nomenclature used in this standard are defined in
IEC 61162-400, annex A.
Annexes A, B and C form an integral part of this standard. Annex D is for information only.
The committee has decided that the contents of this publication will remain unchanged until
June 2005. At this date, the publication will be
• reconfirmed;
• withdrawn;
• replaced by a revised edition, or
• amended.
– 8 – 61162-401  IEC:2001(E)
INTRODUCTION
International Standard IEC 61162 is a four-part standard which specifies four digital interfaces
for applications in marine navigation, radiocommunication and system integration.
The four parts are:
IEC 61162-1 Single talker and multiple listeners
IEC 61162-2 Single talker and multiple listeners, high speed transmission
IEC 61162-3 Multiple talkers and multiple listeners – Serial data instrument network
IEC 61162-4 Multiple talkers and multiple listeners – Ship systems interconnection.
Part 4 of the standard is sub-divided into a number of individual standards with part numbers
in the IEC 61162-400 series. A full reference to part 4 can be found in IEC 61162-400,
clause 4.
This part of the standard, IEC 61162-401: A-profile specification, defines the application
functionality and its implementation in an application layer protocol.
Relationship with the other parts of the IEC 61162 series of standards is defined in annex B to
IEC 61162-400.
61162-401  IEC:2001(E) – 9 –
MARITIME NAVIGATION AND RADIOCOMMUNICATION
EQUIPMENT AND SYSTEMS –
DIGITAL INTERFACES –
Part 401: Multiple talkers and multiple listeners –
Ship systems interconnection – Application profile
1 Scope
1.1 General
IEC 61162-4 series specifies a communication system for use in integrated ship control
systems.
IEC 61162-400 defines the overall functional scope for the communication system.
1.2 Application profile
This part of IEC 61162 describes the application profile (A-profile – corresponding to ISO-OSI
layers 5 to 7 [ISO 7498]) of the communication protocol which is the basis for the
communication system. It relies on the realization of layers 1 to 4 (the T-profile) as described
in part 410.
The description of the A-profile is in terms of services offered to the application using the
protocol and of message contents and sequences used to realize these services.
2 Normative references
The following normative documents contain provisions which, through reference in this text,
constitute provisions of this part of IEC 61162. For dated references, subsequent amend-
ments to, or revisions of, any of these publications do not apply. However, parties to
agreements based on this part of IEC 61162 are encouraged to investigate the possibility of
applying the most recent editions of the normative documents indicated below. For undated
references, the latest edition of the normative document referred to applies. Members of IEC
and ISO maintain registers of currently valid International Standards.
IEC 61162-400, Maritime navigation and radiocommunication equipment and systems –
Digital interfaces – Part 400: Multiple talkers and multiple listeners – Ship systems
interconnection – Introduction and general principles
IEC 61162-410, Maritime navigation and radiocommunication equipment and systems –
Digital interfaces – Part 410: Multiple talkers and multiple listeners – Ship systems
interconnection – Transport profile requirements and basic transport profile
IEC 61162-420, Maritime navigation and radiocommunication equipment and systems –
Digital interfaces – Part 420: Multiple talkers and multiple listeners – Ship systems
interconnection – Companion standard requirements and basic companion standards
IEEE 754: IEEE Standard for Binary Floating-Point Arithmetic
ISO/IEC 8859-1, Information technology – 8-bit single-byte coded graphic character sets –
Part 1: Latin alphabet No. 1
– 10 – 61162-401  IEC:2001(E)
ISO/IEC 10646-1, Information Technology – Universal Multiple-Octet Coded Character Set
(UCS) – Part 1: Architecture and Basic Multilingual Plane
RFC 2500:1999, Internet Official Protocol Standards – Internet Activities Board standard
NOTE RFC (request for comments) is a document issued by the Internet engineering task force (IETF), the
International standardization body for the Internet, that describes a part of the Internet protocol. Some RFCs are
accepted as official Internet standards and listed in the “Internet Official Protocol Standards” itself an RFC.
3 Definitions
This clause is divided into definition of terms (terms), definition of abbreviations
(abbreviations), definitions of nomenclature (conventions), definition of data types (data
types) and definition of literal formats. Other definitions valid for this part of IEC 61162 are
contained in part 400 of this standard.
3.1 Terms
For the purpose of this part of IEC 61162, the following terms apply:
3.1.1
anonymous broadcast (ABC)
a broadcast service where the sender does not know to which MAU it is sending data.
Similarly the listener may not know which sender it should listen for
3.1.2
array
a linear indexed sequence of identical data types. The index runs from zero and upwards.
Arrays can have variable lengths (with a fixed upper limit) or fixed lengths. The difference
between these two types is normally only visible during transmission between modules where
the real length of a variable length array is transmitted as an attribute
3.1.3
bit order
this standard numbers bits in an octet from zero to seven. Bit seven is the most significant bit;
bit zero the least significant
3.1.4
character
this standard provides two mechanisms for the transmission of characters:
a) an 8-bit character based on ISO/IEC 8859-1 (also called ISO Latin-1). This set covers
most national alphabets based on the Latin letters;
b) a 16-bit character based on ISO/IEC 10646-1. This standard specifies the use of the 16-
bit form Universal Character Set 2 (UCS-2) which covers most of the commonly used
character sets in the world
NOTE 1 Later revisions of the standard may also support 32-bit characters.
NOTE 2 Any reference to character in this standard implies the 8-bit character if not otherwise stated.
3.1.5
companion standard
these are the mechanisms to define and describe how the A-profile services are used to
implement some application functions and interfaces (see IEC 61162-420)
3.1.6
connection
an association between two interfaces or two MCPs, one each on a server and a client MAU.
A connection must be established before transactions can be activated

61162-401  IEC:2001(E) – 11 –
There is also a connection between each pair of LNAs and between each MAU and its LNA.
Although similar in concept, they are not directly associated with the activation of
transactions.
3.1.7
data type
this standard defines a set of data types that have a machine and T-profile independent
interpretation. The types cover, for example characters, signed and unsigned integers and
floating point containers as well as some other derived types. The data types are defined
in 3.4
3.1.8
format string
a text string that defines the structure of certain data records that are transmitted via the
T-profile. It also contains information about the function supported by data objects. See
clause 8.4.3.5 for more information
3.1.9
interface
a collection of MCPs (references to data objects) implemented on a server or client MAU
which behaves similarly to MCPs in that operations on interfaces effect all MCPs in the
interface
3.1.10
IP – internet protocol
references in this standard refer to the protocol defined in RFC 2500. Part 410 of IEC 61162
specifies a T-profile using version 4 of the internet protocol (IPV4), but additional parts may in
the future define T-profiles using newer versions of the protocol
3.1.11
IPV4 – internet protocol version 4
is currently the most used version of the internet protocol (IP). See IEC 61162-410 for more
details
3.1.12
magic number
The first field of all messages which will be common to a group of messages. It can be used
by the protocol software to identify and verify messages and message boundaries. See
annex A
3.1.13
maximum message size
this protocol is based on the exchange of messages between various modules. The T-profile
may impose limits on the maximum size of these messages. See clause 4 for more information
3.1.14
message
one of the basic components of this standard. They are collections of information items with a
defined format that are exchanged between various modules to achieve some service or part
service. The message formats are defined in clause 8. The exchange patterns are defined as
sequence diagrams in clause 7
3.1.15
module
entities (programs or host computers) between messages that are sent which are either an
LNA (application independent network communication manager) or a MAU (the application
program module)
– 12 – 61162-401  IEC:2001(E)
3.1.16
network bit order
the A-profile definition is resolved to the octet level. The ordering of bits within each octet is
defined by the T-profile in use. See clause 4 for more information
3.1.17
network octet order
all multi-octet entities (messages or fragments of messages) are defined to be transferred in a
T-profile and host computer independent format. This format is defined in 8.4.3.5
3.1.18
null MCP
an MCP associated with the MAU itself. It will have a reference code of zero. It can be
manipulated similarly to a normal MCP through the MAU control data object (see 6.5) and it
can also be used to transfer information to MAU call back routines (see 5.2.4). The null MCP
cannot be connected to from remote MAUs and it is not associated with any interface
3.1.19
octet
the smallest information entity that the A-profile protocol considers which consists of 8 bits
transmitted by the T-profile in some specific sequence. This standard requires that a group of
octets can be transmitted as a message and that the received message has the same
sequence of octets as the sent message and that each received octet has the same bit
pattern as the sent octet. The protocol does not specify any particular ordering of bits within
octets as long as it is consistent over the network
NOTE One entity of the Boolean type can be represented as a bit within an octet, but any number of Boolean
entities will be transmitted as an integral number of octets.
3.1.20
record
a sequence of different or identical data types given a fixed definition and an associated type
name
3.1.21
sequence diagram
a representation of how messages are transferred between the modules of the protocol
system. The format is defined in 3.3.3
3.1.22
session
the term is used to identify a connection from a client MAU to a server MAU. It represents one
unbroken connection where the LNAs guarantee that no other client MAU has replaced the
originally connecting MAU. The death of a client MAU will be reported to the server MAU as a
closed session
3.1.23
T-profile network
a collection of network nodes (host computers) that can communicate with each other
following this standard. The concept is defined in IEC 61162-410.
This standard does not specify how nodes on two different T-profile networks shall communicate
NOTE The standard does, however, specify that one node shall be able to be connected to more than one
T-profile network at one time and this can be used to develop gateway nodes.
3.1.24
TCP/IP – transmission control protocol / internet protocol
for version 4 of the internet protocol (IPV4) is defined in RFC793. See IEC 61162-410 for
more details
61162-401  IEC:2001(E) – 13 –
3.1.25
transaction
the term is used to identify an exchange of data between two MAUs that is related to one
initial request from the client. It can consist of from zero (non-acknowledged write) to an
unlimited number (subscriptions) of messages from the server
3.1.26
version number
in this standard, it is 4.0 (major number is 4, minor is 0). Earlier version codes have been
used by MiTS (see IEC 61162-400)
3.2 Abbreviations
Table 1 lists important abbreviations used in this standard. The third column gives a reference
to the clause where a definition of the term can be found.
Table 1 – Abbreviations
Term Description Reference
ABC Anonymous broadcast 3.1.1
Ack Acknowledge Figures & text
IPC Inter-process communication 11.1
IP Internet protocol 3.1.10
IPV4 Internet protocol version 4 3.1.11
LNA Local network administrator Part 400
MAU MiTS application unit (application program module) Part 400
MCP MAU connection point 5.3
MTU Maximum transmission unit 4.1
Obj Object Figures & text
Req Request Figures & text
RLNA Remote LNA (in sequence diagram) 3.3.3
RMAU Remote MAU (in sequence diagram) 3.3.3
TCP/IP Transmission control protocol/internet protocol 3.1.24
UCS Universal character set 3.1.4
3.3 Conventions
3.3.1
use of type face
each description element has its own conventions for use of type face. In this standard, the
following conventions apply:
a) use of courier type face indicates either some defined protocol data type (see next item)
or another protocol identifier (e.g. a message code, see 3.3.2);
b) use of the extension _m in a word type set in courier means that it references one of the
defined protocol data types. The types are defined in 3.4;
c) italics are normally used when a word or term references a label or identifier in an
associated table or figure.
3.3.2
message definition template
this standard describes a message based protocol. Each message will be described as an
ordered list of fields. An example is shown in table 2.

– 14 – 61162-401  IEC:2001(E)
Table 2 – Example of message definition
Octet # Data type Field description
word16_m MV4_MAGIC
0 – 1
word16_m
2 – 3 type, message type
word16_m
4 – 5 Priority
word16_m
6 – 7 length, message length (= x+1 or y+1)
8 – x message body necessary
– y message body sometimes required
The message definition has three columns.
a) The first column gives the octet numbers used by a field, numbered from the first to the
last octet inclusive of the field. The numbering starts with 0 at the first octet of the
message. The letters x, y, etc. are used to indicate the last byte number in a variable
length field. Arithmetic expressions may also be indicated in this column. Arithmetic
expressions are enclosed in parenthesis.
b) The second column gives the data type of the field (see 3.1.7 and 3.4.2).
c) The third column describes the contents of the field. Identifiers in courier show constant
values. The value of these can be found in the annexes. Expressions typeset in italics are
described in the text following the message definition.
The physical message consists of the entities defined in the table transmitted as a sequence
of (multi-octet) quantities. A message may consist of one part that is always transmitted and
one part that is sometimes transmitted. The limit between these two parts is shown by a thick
row divider line in the table
3.3.3
sequence diagrams
message sequences are described in diagrams. An example is shown in figure 1
MAU LNA RLNA RMAU
MAPI_AREQ
CC_REQMAU
CC_REQMAU
EXAMPLE
CC_DEFMAUEXAMPLE
LL_MAUREQ(N)
LL_MAUACK
Repeat until answered, RETRY_INTERVAL
Avoided if already in LNAs database
Triggered by connection of MAU
IEC  2361/01
Figure 1 – Sequence diagram example
The following graphical elements are used:
– each communicating module is represented by a vertical dashed line. The upper list of
names identify the modules. The same module list will be used in all diagrams (the
modularization is defined in IEC 61162-400):
1) MAU is the local application unit communicating with its LNA;
2) LNA is the local communication manager communicating with MAU and RLNA;

61162-401  IEC:2001(E) – 15 –
3) RLNA is the remote communication manager communicating with LNA and RMAU;
4) RMAU is the remote application unit communicating with its RLNA;
NOTE When two MAUs which are connected to the same LNA are communicating, the LNA – RLNA
communication sequence may depend on the implementation. However, it is recommended that the implementation
uses th
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