ISO/IEC 20114:2004

Information technology — Telecommunications and information exchange between systems — Private Integrated Services Network (PISN) — Inter-exchange signalling protocol — Make call request supplementary service

ISO/IEC 20114:2004 specifies the signalling protocol for the support of the Make Call Request supplementary service (SS-MCR) at the Q reference point between Private Integrated services Network eXchanges (PINXs) connected together within a Private Integrated Services Network (PISN). Supplementary service MCR enables a Requesting User to request a Co-operating User to establish a new Requested Call to a Destination User. This new Requested Call between the Co-operating and Destination User can be either a Basic call or a Call Independent Signalling Connection. The Q reference point is defined in ISO/IEC 11579-1. Service specifications are produced in three stages and according to the method specified in ETS 300 387. ISO/IEC 20114:2004 contains the stage 3 specification for the Q reference point and satisfies the requirements identified by the stage 1 and stage 2 specifications in ISO/IEC 20113. The signalling protocol for SS-MCR operates on top of the signalling protocol for basic circuit switched call control, as specified in ISO/IEC 11572, and uses certain aspects of the generic procedures for the control of supplementary services specified in ISO/IEC 11582. ISO/IEC 20114:2004 also specifies additional signalling protocol requirements for the support of interactions at the Q reference point between SS-MCR and other supplementary services and ANFs. ISO/IEC 20114:2004 is applicable to PINXs, which can interconnect to form a PISN.

Technologies de l'information — Télécommunications et échange d'information entre systèmes — Réseau privé à intégration de services — Protocole de signalisation d'échange — Service supplémentaire de demande par appel

General Information

• Status: Published
• Publication Date: 20-May-2004
• ICS: 33.040.35 - Telephone networks
• Technical Committee: ISO/IEC JTC 1/SC 6 - Telecommunications and information exchange between systems
• Drafting Committee: ISO/IEC JTC 1/SC 6 - Telecommunications and information exchange between systems
• Current Stage: 9060 - Close of review
• Start Date: 02-Dec-2025

Standards Content (Sample)

INTERNATIONAL ISO/IEC
STANDARD 20114
First edition
2004-05-15

Information technology —
Telecommunications and information
exchange between systems — Private
Integrated Services Network (PISN) —
Inter-exchange signalling protocol —
Make call request supplementary service
Technologies de l'information — Télécommunications et échange
d'information entre systèmes — Réseau privé à intégration de
services — Protocole de signalisation d'échange — Service
supplémentaire de demande par appel




Reference number
ISO/IEC 20114:2004(E)
©
ISO/IEC 2004

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ISO/IEC 20114:2004(E)
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©  ISO/IEC 2004
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ISO/IEC 20114:2004(E)
Contents Page
Foreword. iv
Introduction . v
1 Scope. 1
2 Conformance. 1
3 Normative references. 1
4 Terms and definitions. 2
4.1 External definitions. 2
4.2 Other definitions. 3
5 Acronyms. 4
6 Signalling Protocol for the support of SS-MCR.4
6.1 SS-MCR description. 4
6.2 SS-MCR operational requirements. 4
6.3 SS-MCR coding requirements . 6
6.4 SS-MCR state definitions . 9
6.5 SS-MCR signalling procedures . 10
6.6 SS-MCR impact of interworking with public ISDNs. 13
6.7 SS-MCR impact of interworking with non-ISDNs . 13
6.8 Protocol interactions between SS-MCR and other supplementary services and ANFs. 13
6.9 SS-MCR parameter values (Timers) . 16
Annex A (normative) Protocol Implementation Conformance Statement (PICS) Proforma . 17
A.1 Introduction. 17
A.2 Instructions for completing the PICS proforma.17
A.3 PICS proforma for ISO/IEC 20114. 18
Annex B (informative) Examples of Message Sequences. 21
B.1 Example message sequences for invocation and operation of SS-MCR. 22
Annex C (informative) Specification and Description Language (SDL) Representation of
Procedures . 26
C.1 SDL representation of SS-MCR at the Requesting PINX . 27
C.2 SDL representation of SS-MCR at the Co-operating PINX. 28
C.3 SDL representation of SS-MCR at the Destination PINX . 29

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ISO/IEC 20114:2004(E)
Foreword
ISO (the International Organization for Standardization) and IEC (the International Electrotechnical
Commission) form the specialized system for worldwide standardization. National bodies that are members of
ISO or IEC participate in the development of International Standards through technical committees
established by the respective organization to deal with particular fields of technical activity. ISO and IEC
technical committees collaborate in fields of mutual interest. Other international organizations, governmental
and non-governmental, in liaison with ISO and IEC, also take part in the work. In the field of information
technology, ISO and IEC have established a joint technical committee, ISO/IEC JTC 1.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of the joint technical committee is to prepare International Standards. Draft International
Standards adopted by the joint technical committee are circulated to national bodies for voting. Publication as
an International Standard requires approval by at least 75 % of the national bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO and IEC shall not be held responsible for identifying any or all such patent rights.
ISO/IEC 20114 was prepared by ECMA (as ECMA-344) and was adopted, under a special “fast-track
procedure”, by Joint Technical Committee ISO/IEC JTC 1, Information technology, in parallel with its approval
by national bodies of ISO and IEC.

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ISO/IEC 20114:2004(E)
Introduction
This International Standard is one of a series defining services and signalling protocols applicable to Private
Integrated Services Networks (PISNs). The series uses ISDN concepts as developed by ITU-T and conforms
to the framework of International Standards for Open Systems Interconnection as defined by ISO/IEC.
This International Standard specifies the signalling protocol for use at the Q reference point in support of the
Make Call Request supplementary service. The protocol defined in this International Standard forms part of
the PSS1 protocol (informally known as QSIG).
This International Standard is based upon the practical experience of ECMA member companies and the
results of their active and continuous participation in the work of ISO/IEC JTC1, ITU-T, ETSI and other
international and national standardization bodies. It represents a pragmatic and widely based consensus.

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INTERNATIONAL STANDARD ISO/IEC 20114:2004(E)

Information technology — Telecommunications and information
exchange between systems — Private Integrated Services
Network (PISN) — Inter-exchange signalling protocol — Make
call request supplementary service
1 Scope
This International Standard specifies the signalling protocol for the support of the Make Call Request
supplementary service (SS-MCR) at the Q reference point between Private Integrated services Network
eXchanges (PINXs) connected together within a Private Integrated Services Network (PISN).
Supplementary service MCR enables a Requesting User to request a Co-operating User to establish a new
Requested Call to a Destination User. This new Requested Call between the Co-operating and Destination
User can be either a Basic call or a Call Independent Signalling Connection.
The Q reference point is defined in ISO/IEC 11579-1.
Service specifications are produced in three stages and according to the method specified in ETS 300 387.
This International Standard contains the stage 3 specification for the Q reference point and satisfies the
requirements identified by the stage 1 and stage 2 specifications in ISO/IEC 20113.
The signalling protocol for SS-MCR operates on top of the signalling protocol for basic circuit switched call
control, as specified in ISO/IEC 11572, and uses certain aspects of the generic procedures for the control of
supplementary services specified in ISO/IEC 11582.
This International Standard also specifies additional signalling protocol requirements for the support of
interactions at the Q reference point between SS-MCR and other supplementary services and ANFs.
This International Standard is applicable to PINXs, which can interconnect to form a PISN.
2 Conformance
In order to conform to this International Standard, a PINX shall satisfy the requirements identified in the
Protocol Implementation Conformance Statement (PICS) proforma in Annex A.
Conformance to this International Standard includes conforming to those clauses that specify protocol
interactions between SS-MCR and other supplementary services and ANFs for which signalling protocols at
the Q reference point are supported in accordance with the stage 3 standards concerned.
3 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.
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ISO/IEC 20114:2004(E)
ISO/IEC 11572:2000, Information technology — Telecommunications and information exchange between
systems — Private Integrated Services Network — Circuit mode bearer services — Inter-exchange signalling
procedures and protocol
ISO/IEC 11579-1:1994, Information technology — Telecommunications and information exchange between
systems — Private integrated services network — Part 1: Reference configuration for PISN Exchanges (PINX)
ISO/IEC 11582:2002, Information technology — Telecommunications and information exchange between
systems — Private Integrated Services Network — Generic functional protocol for the support of
supplementary services — Inter-exchange signalling procedures and protocol
ISO/IEC 20113:2004, Information technology — Telecommunications and information exchange between
systems — Private Integrated Services Network — Specification, functional model and information flows —
Make call request supplementary service
ISO/IEC 20115:2004, Information technology — Telecommunications and information exchange between
systems — Private Integrated Services Network — Use of QSIG for Message Centre Access (MCA) profile
standard
ETS 300 387:1994, Private Telecommunication Network (PTN); Method for the specification of basic and
supplementary services
ITU-T Rec. I.112:1993, Vocabulary of terms for ISDNs
ITU-T Rec. I.210:1993, Principles of telecommunication services supported by an ISDN and the means to
describe them
ITU-T Rec. Q.950:2000, Digital Subscriber Signalling System No. 1 (DSS 1) — Supplementary services
protocols, structure and general principles
ITU-T Rec. Z.100:1999, Specification and Description Language
4 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
4.1 External definitions
This International Standard uses the following terms defined in other documents:
 Application Protocol Data Unit (APDU) (ISO/IEC 11582)
 Call, Basic call (ISO/IEC 11582)
 Call Independent Signalling Connection (ISO/IEC 11582)
 Call-Independent (ISO/IEC 11582)
 Gateway PINX (ISO/IEC 11582)
 Originating PINX (ISO/IEC 11582)
 Private Integrated Services Network (PISN) (ISO/IEC 11579-1)
 Private Integrated services Network eXchange (PINX) (ISO/IEC 11579-1)
 Signalling (ITU-T Rec. I.112)
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ISO/IEC 20114:2004(E)
 Supplementary Service (ITU-T Rec. I.210)
 Supplementary Service Control Entity (ISO/IEC 11582)
 Terminating PINX (ISO/IEC 11582)
 Transit PINX (ISO/IEC 11582)
4.2 Other definitions
4.2.1
Co-operating PINX
The PINX where the Co-operating User is located.
4.2.2
Co-operating User
The user who receives a Make Call Request and who shall set up a new Requested Call to the Destination
User.
4.2.3
Destination PINX
The PINX where the Destination User is located.
4.2.4
Destination User
The called user of the Requested Call i.e. the user to whom the Co-operating User shall establish a
Requested Call.
4.2.5
Make Call Request
A request from the Requesting User for a new call (i.e. Requested Call) between a Co-operating User and a
Destination User.
4.2.6
Original Call
The call between the Requesting User and the Co-operating User. The Original Call can be either a Basic call
or a Call Independent Signalling Connection and is correlated with the Requested Call.
4.2.7
Requested Call
The call between the Co-operating User and the Destination User that is established by the Co-operating User
due to a Make Call Request from the Requesting User. The Requested Call can either be a Basic call (with a
specific Basic Service) or a Call Independent Signalling Connection and is correlated with the Original Call.
4.2.8
Requesting PINX
The PINX where the Requesting User is located.
4.2.9
Requesting User
The User who sends a Make Call Request to the Co-operating User with the request to establish a specific
Requested Call to the Destination User.
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ISO/IEC 20114:2004(E)
5 Acronyms
ANF Additional Network Feature
APDU Application Protocol Data Unit
ASN.1 Abstract Syntax Notation One
CISC Call Independent Signalling Connection
ISDN Integrated Services Digital Network
NFE Network Facility Extension
PICS Protocol Implementation Conformance Statement
PINX Private Integrated services Network eXchange
PISN Private Integrated Services Network
SDL Specification and Description Language
SS Supplementary Service
SS-MCR Supplementary Service Make Call Request
6 Signalling Protocol for the support of SS-MCR
6.1 SS-MCR description
The supplementary service MCR enables a Requesting User to request a Co-operating User to establish a
new Requested Call to a Destination User. This new Requested Call between the Co-operating User and the
Destination User can either be a Basic call or a Call Independent Signalling Connection. The new Requested
Call is correlated to the Original Call between the Requesting and Co-operating User.
6.2 SS-MCR operational requirements
6.2.1 Requirements on a Requesting PINX
Call establishment procedures for the incoming and outgoing side of an inter-PINX link and call release
procedures, as specified in ISO/IEC 11572, shall apply.
Generic procedures for call-related control of supplementary services, as specified in ISO/IEC 11582 for an
End PINX, shall apply.
Generic procedures for the call-independent control (connection-oriented) of supplementary services, as
specified in ISO/IEC 11582 for an Originating PINX and for a Terminating PINX, shall apply.
6.2.2 Requirements on a Co-operating PINX
Call establishment procedures for the incoming and outgoing side of an inter-PINX link and call release
procedures, as specified in ISO/IEC 11572, shall apply.
Generic procedures for call-related control of supplementary services, as specified in ISO/IEC 11582 for an
End PINX, shall apply.
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ISO/IEC 20114:2004(E)
Generic procedures for the call-independent control (connection-oriented) of supplementary services, as
specified in ISO/IEC 11582 for a Terminating PINX and for an Originating PINX, shall apply.
6.2.3 Requirements on a Destination PINX
Call establishment procedures for the incoming and outgoing side of an inter-PINX link and call release
procedures, as specified in ISO/IEC 11572, shall apply.
Generic procedures for call-related control of supplementary services, as specified in ISO/IEC 11582 for an
End PINX, shall apply.
Generic procedures for the call-independent control (connection-oriented) of supplementary services, as
specified in ISO/IEC 11582 for a Terminating PINX and for an Originating PINX, shall apply.
6.2.4 Requirements on a Transit PINX
Basic call procedures specified in ISO/IEC 11572 for a Transit PINX shall apply.
Generic procedures for call-related control of supplementary services, as specified in ISO/IEC 11582 for a
Transit PINX, shall apply.
Generic procedures for the call-independent control (connection-oriented) of supplementary services, as
specified in ISO/IEC 11582 for a Transit PINX, shall apply.
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ISO/IEC 20114:2004(E)
6.3 SS-MCR coding requirements
6.3.1 Operations
The operations defined in Abstract Syntax Notation number 1 (ASN.1) in Table 1 shall apply.
Table 1 — Operations in support of SS-MCR
SS-MCR-Operations-asn97
{iso (1) identified-organization (3) icd-ecma (12) standard (0)
qsig-make-call-request (344) make-call-request-operations (0)}

DEFINITIONS EXPLICIT TAGS ::=

BEGIN

IMPORTS

OPERATION,
ERROR
FROM Remote-Operations-Information-Objects
{ joint-iso-itu-t (2) remote-operations (4) informationObjects (5) version1 (0) }

EXTENSION,
Extension {}
FROM Manufacturer-specific-service-extension-class-asn1-97
{ iso (1) standard (0) pss1-generic-procedures (11582) msi-class-asn1-97 (11) }

Name
FROM Name-Operations-asn1-97
{ iso (1) standard (0) pss1-name (13868) name-operations-asn1-97 (1) }

BasicService
FROM Call-Diversion-Operations-asn1-97
{ iso (1) standard (0) pss1-call-diversion (13873)
 call-diversion-operations-asn1-97 (1) }

basicServiceNotProvided,
supplementaryServiceInteractionNotAllowed,
userNotSubscribed
FROM General-Error-List
{itu-t (0) recommendation (0) q (17) 950 (950) general-error-list (1)}

PresentedAddressUnscreened
FROM Addressing-Data-Elements-asn1-97
{ iso (1) standard (0) pss1-generic-procedures (11582)
 addressing-data-elements-asn1-97 (20) }

CallIdentity, establishmentFailure
FROM Path-Replacement-Operations-asn1-97
{iso (1) standard (0) pss1-path-replacement (13874) pr-operations-asn1-97(1)}
;

Make-Call-Request-Operations OPERATION::= {
mCRequest | mCAlerting | mCInform }


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ISO/IEC 20114:2004(E)
Table 1 — Operations in support of SS-MCR (continued)
mCRequest  OPERATION ::= {
      ARGUMENT    MCRequestArg
      RESULT     MCRequestResult
      ERRORS     {userNotSubscribed|
              basicServiceNotProvided|
              supplementaryServiceInteractionNotAllowed|
              invalidDestinationNumber|
              invalidCooperationNumber|
              mCRequestNotAllowed|
              mCExecutionNotAllowed|
              mCDestUserBusy|
              mCCoopUserBusy|
              mCCoopUserRejected|
              establishmentFailure|
              unspecified}
      CODE      local: 112
             }

mCInform  OPERATION ::= {
      ARGUMENT    MCInformArg
      RETURN RESULT  FALSE
      ALWAYS RESPONDS FALSE
      ERRORS     {userNotSubscribed|
              basicServiceNotProvided|
              supplementaryServiceInteractionNotAllowed|
              invalidDestinationNumber|
              mCExecutionNotAllowed|
              mCDestUserBusy|
              unspecified}
      CODE      local: 113
              }

mCAlerting OPERATION ::= {
      ARGUMENT    MCAlertingArg
      RETURN RESULT  FALSE
      ALWAYS RESPONDS FALSE
      CODE      local: 114
             }

MCRequestArg  ::=   SEQUENCE
      {
      callType       CallType,
      retainOrigCall    BOOLEAN DEFAULT TRUE,
      destinationAddress  PresentedAddressUnscreened,
      requestingAddress   [0] PresentedAddressUnscreened OPTIONAL,
      cooperatingAddress  [1] PresentedAddressUnscreened OPTIONAL,
      correlation      Correlation,
      extensions      MCRExtensions   OPTIONAL,
      .
      }

MCRequestResult ::=  SEQUENCE
      {
      extensions      MCRExtensions   OPTIONAL,
      .
      }

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ISO/IEC 20114:2004(E)
Table 1 — Operations in support of SS-MCR (concluded)
MCInformArg    ::=  SEQUENCE
      {
      requestingAddress    [0] PresentedAddressUnscreened OPTIONAL,
      cooperatingAddress    [1] PresentedAddressUnscreened OPTIONAL,
      correlation       Correlation,
      extensions        MCRExtensions   OPTIONAL,
      .
      }

MCAlertingArg    ::=  SEQUENCE
      {
      correlation       Correlation,
      extensions        MCRExtensions   OPTIONAL,
      .
      }
CallType    ::=  CHOICE
      {
      basicService       BasicService,
      cisc           NULL
      }

Correlation  ::=  SEQUENCE
      {
      correlationData     CallIdentity,
      correlationReason    CorrelationReason  OPTIONAL
      }
CorrelationReason  ::=  INTEGER
      {
      unknown       (0),
      mCACommunication  (1),
      cTIApplication   (2)
      } (0.255)

MCRExtensions  ::= CHOICE
      {
      none    NULL,
      single   [0] IMPLICIT Extension
              { { MakeCallRequestExtension } } ,
      multiple  [1] IMPLICIT SEQUENCE OF Extension
              { { MakeCallRequestExtension } }
      }

MakeCallRequestExtension EXTENSION::= {.}

invalidDestinationNumber  ERROR ::= {CODE local : 1030}
invalidCooperationNumber  ERROR ::= {CODE local : 1031}
mCRequestNotAllowed    ERROR ::= {CODE local : 1032}
mCExecutionNotAllowed   ERROR ::= {CODE local : 1033}
mCDestUserBusy       ERROR ::= {CODE local : 1034}
mCCoopUserBusy       ERROR ::= {CODE local : 1035}
mCCoopUserRejected     ERROR ::= {CODE local : 1036}
unspecified        ERROR ::= {PARAMETER Extension
                { { MakeCallRequestExtension } }
              CODE local : 1008
                   }

END    -- of SS-MCR-Operations

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ISO/IEC 20114:2004(E)
6.3.2 Information elements
6.3.2.1 Facility information element
The operations defined in 6.3.1 shall be coded in the Facility information element in accordance with
ISO/IEC 11582.
When conveying the invoke APDUs of the operations defined in 6.3.1, the destination Entity data element of
the NFE shall contain the value endPINX.
When conveying the invoke APDU of operation mCRequest defined in 6.3.1, the interpretation APDU shall be
set to value rejectAnyUnrecognisedInvokePdu or shall be omitted.
When conveying the invoke APDU of operation mCInform or mCAlerting defined in 6.3.1, the interpretation
APDU shall be set to value discardAnyUnrecognisedInvokePdu.
6.3.2.2 Other information elements
Any other information element shall be coded in accordance with ISO/IEC 11572.
6.3.3 Messages
The Facility information element shall be conveyed in messages as specified in Clause 10 of ISO/IEC 11582.
6.4 SS-MCR state definitions
6.4.1 States at the Requesting PINX
The procedures for the Requesting PINX are written in terms of the following conceptual states existing within
the SS-MCR Control entity in that PINX in association with a particular SS-MCR request from the Requesting
User.
6.4.1.1 State MCR-Idle
SS-MCR is not operating.
6.4.1.2 State MCR-Active
SS-MCR is operating. A mCRequest invoke APDU was sent to the Co-operating PINX. The Requesting PINX
awaits the result of this operation.
6.4.2 States at the Co-operating PINX
The procedures for the Co-operating PINX are written in terms of the following conceptual states existing
within the SS-MCR Control entity in that PINX.
6.4.2.1 State MCR-Idle
SS-MCR is not operating.
6.4.2.2 State MCR-Active
SS-MCR is operating. Call establishment of the requested call is initiated by the Co-operating PINX and a
mCInform invoke APDU was sent towards the Destination PINX. The Co-operating PINX awaits the result of
the call establishment.
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ISO/IEC 20114:2004(E)
6.4.3 States at the Destination PINX
No SS-MCR specific states required.
6.5 SS-MCR signalling procedures
Examples of message sequences are shown in Annex B.
6.5.1 Actions at the Requesting PINX
The SDL representation of procedures at the Requesting PINX is shown in Clause C.1 of Annex C.
6.5.1.1 Normal procedures
6.5.1.1.1 Activation / deactivation / interrogation
Not applicable.
6.5.1.1.2 Invocation and operation
In state MCR-Idle, due to a request from the Requesting User, the Requesting PINX shall send a mCRequest
invoke APDU to the Co-operating PINX, start Timer T1 and enter state MCR-Active.
For the transport of this mCRequest invoke APDU the Requesting PINX shall either use the Call Reference of
an already existing Basic Call or an already existing Call Independent Signalling Connection or set up a new
Call Independent Signalling Connection in accordance with the procedures specified in 7.3 of ISO/IEC 11582.
In the case of set up of a new Call Independent Signalling Connection, the Requesting PINX is responsible for
the clearing of this connection.
The elements callType, retainOrigCall, destinationAddress, requestingAddress, cooperatingAddress and
correlation of the mCRequest invoke APDU shall be set according to the request of the Requesting User.
NOTE Provision of element cooperatingAddress is required when a new CISC is to be established. If mCRequest.inv
is sent on the call reference of an already existing connection, the Co-operating User is the User served on this call
reference at the Co-operating PINX.
In state MCR-Active, on receipt of a mCAlerting invoke APDU from the Co-operating PINX, the Requesting
PINX may indicate the result to the Requesting User, if the capability exists, and remain in state MCR-Active.
In state MCR-Active, on receipt of a mCRequest return result APDU from the Co-operating PINX, the
Requesting PINX shall stop Timer T1, may indicate the result to the Requesting User if the capability exists,
and shall enter state MCR-Idle.
6.5.1.2 Exceptional procedures
6.5.1.2.1 Activation / deactivation / interrogation
Not applicable.
6.5.1
...