ISO/IEC 9574:1989

Information technology — Telecommunications and information exchange between systems — Provision of the OSI connection-mode network service by packet mode terminal equipment connected to an integrated services digital network (ISDN)

Technologies de l'information — Télécommu- nications et échange d'informations entre systèmes — Fourniture du service de réseau OSI en mode connexion par un terminal en mode paquet raccordé à un réseau numérique avec intégration des services (RNIS)

General Information

• Status: Withdrawn
• Publication Date: 06-Dec-1989
• Withdrawal Date: 06-Dec-1989
• ICS: 35.100.30 - Network layer
• 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: 9599 - Withdrawal of International Standard
• Completion Date: 30-Dec-1992

Relations

• Revised: ISO/IEC 9574:1992 - Information technology — Provision of the OSI connection-mode network service by packet mode terminal equipment to an integrated services digital network (ISDN)
• Effective Date: 15-Apr-2008

Standards Content (Sample)

I NTER NAT1 ON AL
ISOIIEC
STANDARD
First edition
1989- 12-1 5
Information technology - Telecommunications
and information exchange between systems -
Provision of the OS1 connection-mode network
service by packet mode terminal equipment
connected to an integrated services digital
network (ISDN)
Technologies de l'information - Télécommunications et échange d'informations
entre systèmes - Fourniture du service de réseau OS/ en mode connexion par un
terminal en mode paquet raccordé à un réseau numérique avec intégration des
services IRNISI
-a
Reference number
ISO/IEC 9574 : 1989 (E)

---------------------- Page: 1 ----------------------
ISO/IEC 9574 : 1989(E)
Contents Page
Foreword . iii
Section 1 : General . 1
1.1 scope . 1
1.2 Normative references . 1
1.3 Definitions . 2
1.4 Abbreviations . 2
1.5 Overview . 2
Section 2 : Provision of the CONS in systems attached at the S/T reference
point . 4
2.1 Procedures for TE1 s or TE2/TAs to provide CONS . 4
2.2 Additional rocedures for a TE1 or TE2/TA to provide the CONS when
............................................................................... 5
using the ISDlfD channel
2.3 Additional procedures for a TE1 or TE2/TA to provide the CONS when
using the ISDN B channel . 5
Section 3 : Provision of the CONS in systems attached at the R reference
point . 8
3.1 Procedures for TE2s to provide the CONS at the R reference point . 8
3.2 Additional procedures for a TE2 to provide the CONS at the R reference
point . 8
ANNEX
A Bibliography . 11
O ISO/IEC 1989
All rights reserved. No part of this publication may be reproduced or utilized in any form or by any
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writing from the publisher.
ISO/IEC Copyright Office 0 Case postale 56 0 CH-1211 Genève 20 0 Switzerland
Printed in Switzerland
ii

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ISOAEC 9574 : 1989( E)
Foreword
IS0 (the International Organization for Standardization) and IEC (the International
Electrotechnical Commission) together form a system for world wide standardization
as a whole. National bodies that are members of IS0 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. IS0
and IEC technical committees collaborate in fields of mutual interest. Other
international organizations, governmental and non-governmental, in liaison with IS0
and IEC, also take part in the work.
In the field of information technology, IS0 and IEC have established a joint technical
committee, ISO/IEC JTC 1. Draft International Standards adopted by the joint
technical committee are circulated to national bodies for approval before their
acceptance as International Standards. They are approved in accordance with
procedures requiring at least 75% approval by the national bodies voting.
9574 was prepared by Joint Technical Committee
International Standard ISOAEC
ISO/IEC JTC 1, information techno/ogy.
iii

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INTERNATIONAL STANDARD ISOAEC 9574 : 1989 (E)
Informat ion tech nology - Telecommunications and
information exchange between systems - Provision of the
OS1 conn ction-mode network service by packet mode
term i na1 eq u i pmen t connected to n integrated services
digital network (ISDN)
Section 1 : General
IS0 8208 : 1987, Information processing systems - Data
1.1 Scope
communications - X.25 Packet Level Protocol for Data
This International Standard specifies the method of providing
Terminai Equipment.
the OS1 Connection-mode Network Service (CONS) by packet
NOTE - See also CCITT Recommendation X.25
modeterminal equipment connected to an Integrated Services
IS0 8878 : 1987, Information rocessing systems - Data
Digital Network (ISDN) in accordance with the procedures
communications - Use of k)25 to provide the O51
described in CCllT Recommendation X.31. This is done by
connection-mode network service.
specifying the mapping of the CONS primitives and
parameters to and from the elements of the protocols used by
NOTE - See also CCITT Recommendation X.223
two types of packet mode terminal equipment:
CCIU Recommendation 1.231, Circuit-mode bearer service
a) an X.25 DTE (TE2) connected to an R reference point categories.
and accessing an ISDN; and
CCITT Recommendation 1.232, Packet-mode bearer service
b) a packet mode ISDN terminal (TE1) operatin IS0 categories.
8208 packet layer protocol (PLP) and connecte CY to an
CCllT Recommendation 1.430, Basic User-Network Interface
ISDN at either the S or T reference point.
Layer 1 Specification.
NOTE - The definitions of TE1, TE2 and TA equipment, and R,
CCllT Recommendation 1.431, Primary Rate User-Network
S, and T reference points are given in CCITT Recommendation
Interface Layer 1 Specification.
1.41 1. This InternationalStandardappliestoaTEl orTE2iTA,(i.e.,
an OS1 End System) regardless of whether it is a physically
CCllT Recommendation (2.921 (!.441), ISDN User-Network
separate system or embedded in other equipment such as a PBX.
Interface Data Link Layer Specification.
This International Standard addresses the provision of the
CCITT Recommendation Q.931 (!.451), lSDN User-Network
CONS using Virtual Calls as described in CClTT
Interface Layer 3 5pecification.
Recommendation X.25, it does not address the use of X.25
CClU Recommendation V.25 bis, Automatic Answering
Permanent Virtual Circuits.
Equipment and/or Parallel Automatic Calling E uipment on
NOTE - This International Standard uses numbers to identify layers,
the General Switched Telephone Networl Including
rather than their names. This is done to align the terminology of this
Procedures for Disabling of Echo Control Devices for Both
document with the terminology of the related CCITT
Manually and Automatically Established Calls.
Recommendations for ISDN, and does not imply any change in the
functionality of the layers from that defined in the Basic Reference
CCllT Recommendation X.21, lnterface Between Data
Model for Open Systems Interconnection.
Terminal Equipment (D TE) and Daia Circuit-terminating
Equipment (DCE) for Synchronous Operation on Public Data
1.2 Normative references
Networks.
The following standards contain provisions which, through CClTT Recommendation X.21 bis, Use on Public Data
reference in this text, constitute provisions of this International
Networks of Data Terminal Equipment (DTE) which is
to Synchronous V-series Modems.
Standard. At the timeof publication, the editions indicated were Designed for Interfacing
valid. All standards are subject to revision, and parties to
CClTT Recommendation X.31 (1.462, Support of Packet
agreements based on this International Standard are
Mode Terminal Equipment by an ISDN!
encouraged to investigate the possibility of applying the most
CClm Recommendation X.32, lnterface between data
recent editions of the standards listed below. Members of IEC
terminal equi ment (D TE) and data circuit-terminating
and IS0 maintain registers of currently valid International
equipment (DEE) for terminals O erating in the packet mode
Standards.
and accessin a acket switche B public data network through
IS0 7776 : 1986, Information processing systems - Data
apublicswitcfeJelephonenetworkor a circuit switchedpublic
communications - High-level data link control procedures -
data network.
Description of the X.25 LAPB-Compatible DTE data link
NOTE - All references to CCITT Recommendations refer to the text
procedures.
of these Recommendations as approved by the CCITT Plenary
NOTE - See also CCITT Recommendation X.25 Assembly in 1988
1

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ISOllEC 9574 : 1989(E)
1.4 Abbreviations
1.3 Definitions
This International Standard makes use of the following terms.
1.4.1 Reference Model abbreviations
1.3.1 Reference Model definitions (IS0 7498)
NS Network Service
a) Network connection
OS1 Open Systems Interconnection
b) Network Layer
1.4.2 Network service abbreviations
c) Network Service
CONS Connection-mode Network Service
1.3.2 Service conventions definitions (ISOîïR 8509)
QOS Quality of Service
a) Network Service provider
1.4.3 X.25 abbreviations
b) Network Service user
DCE Data Circuit-terminating Equipment
1.3.3 Network Service definitions (IS0 8348)
DTE Data Terminal Equipment
a) N-CONNECT request
LAP Link Access Procedure
b) N-DISCONNECT indication
PLP Packet Layer Protocol
PSDN Packet Switched Data Network
1.3.4 X.25 definitions (IS0 8208)
RPOA Recognized Private Operating Agency
a) DATA packet
b) Data terminal equipment
1.4.4 ISDN abbreviations
c) INCOMING CALL packet
AU Access Unit
d) Throughput class
ISDN Integrated Services Digital Network
e) User data field
PH Packet Handling function
SAPI Service Access Point Identifier
1.3.5 CClTT Recommendation X.31 Definitions
TA Terminal Adaptor
a) Conditional notification class of service
TE Terminal Equipment
b) ISDN Virtual Circuit Bearer Service
HLC Higher Layer Compatibility
c) No notification class of service
d) Packet handling function
1.5 Overview
e) PSPDN Service
1 S.1 ISDN environment
f) Unconditional class of service
The support of the packet mode terminal equipment within the
g) Semi-permanent access (see Note)
scope of this International Standard by an ISDN is described
h) Demand access
in CCllT Recommendation X.31. Throughout this
International Standard references to CCllT Recommendation
NOTE - Some CCllT Recommendations for ISDN use the
(2.931 procedures indicate their use as described in CCllT
term 'permanent' to describe this feature.
Recommendation X.31. Two cases for ISDN support of packet
mode terminal equipment are defined in CCllT
1.3.6 CClTT Recommendation 1.1 12 Definitions
Recommendation X.31: one, the case where the support is via
a) terminal equipment
the ISDN Virtual Circuit Service (see figure 1 a), and the other
where the support is via access to PSDN services (see figure
b) reference point
1 b), respectively referred to as "case B" and "case A".
1.3.7 CClTT Recornmendation 1.41 1 Definitions
In case A an ISDN transparent circuit connection, either
semi-permanent (i.e., non-switched) or demand (i.e.,
a) R reference point
switched), is used. The corresponding ISDN bearer service
b) S reference point
is a 64 kbit/s service as described in CCllT Recommendation
1.231. The sub-network functions available to the user are
c) T reference point
those of the PSDN described in CCllT Recommendation X.25
d) Terminal adaptor
(semi-permanent access) and CCllT Recommendation X.32
(demand access), as well as in other X-Series CClTT
1.3.8 CClTT Recommendation 1.412 Definitions Recommendations (e.g., X.2, X.121).
a) BChannel In case B the ISDN virtual circuit bearer service is used, as
described in CCllT Recommendation 1.232. The sub-network
b) DChannel
functions available are those described in the 1.2~~-Series
CCllT Recommendations.
1.3.9 CClTT Recommendation X.121 Definitions
In case A only B channels ma be used to access the PSDN,
a) prefix
while in case B both B and D cKannels may be used to access
the ISDN packet handling function.
b) escape
2

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ISO/IEC 9574 : 1989(E)
I 1.5.2 CONS in this ISDN environment The requirements for providin CONS in X.25 DTEs
presenting an X.21, X.21 bis, or %.25bis interface at the R
1
ISo 8878 Wecifies the method for roviding the Os!
reference point and connected to an ISDN through a TA are
Connection-mode N&'dork Service (CO86 through the use
specified in section three of this International Standard.
of the X.25 packet layer protocol. When operating in an ISDN
,
This international Standard uses the X.25 PLP to convey all
environment, afew requirements additional to those contained
elements, of all three phases, of the OSi Connection-mode
in IS0 8878 are necessary.
I
Network Service.
The requirements for providing CONS by terminal equipment
I
connected to an ISDN at the S or T reference points are
specified in section two of this International Standard.
I LEGEND:
SORT
TE = TERMINAL
TE1
EQUIPMENT
TA = TERMINAL
ADAPTOR
PH = PACKET
HANDLING
FUNCTION
AU = ACCESS
UNIT
Figure la) - Configurations for case B access
ISDN
SORT SEMI-PERMANENT
I
TE1
ACCESS
R SORT
I TA I
TE 2
U
DEMAND ACCESS
Figure lb) - Configurations for case A access

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ISO/IEC 9574 : 1989(E)
Section 2 : Provision of the CONS in systems attached at the S/T reference
point
The mapping of the elements of the CONS to the protocol and
2.1 Procedures for TEls or TEwTAs to provide
procedures of IS0 8208 shall be as required by IS0 8878 for
CONS
aconformin im lementation that does not use the X.25(1980)
Sub-networ! 8 ependent Convergence Protocol. The
This section of this International Standard covers the three
remaining clauses in this section specify the provisions
cases that exist taking into account the various types of
underlying connections that can be available to the packet required in addition to these mappings, by systems attached
to an interface at the S/T reference point.
mode TE1 or TE2/TA (see table 1). The protocol la ers
applicable to these cases are given in figures 2 and as
referenced in table 1.
Table 1 - Cases covered by section two
Underlying connection perceived by the terminal equipment Figure Subclause
2 2.2
D channel
3 2.3.1
B channel : Semi-permanent
B channel : Demand 3 2.3.2
OS1 LAYER
OS1 LAYER
4
4
THIS INTERNATIONAL STANDARD
THIS INTERNATIONAL STANDARD
J
(2.931 (1.451 ) IS0 8208
(2.931 (1.451) IS0 8208
(see Note) (X.25 PLP)
(see Note) (X.25 PLP)
Q.921 (1.441 ) IS0 7776
2
Q. 921 (I. 441)
(LAPD) (X.25 LAPB)
(LAPD) (see Note)
" "
\
v
D CHANNEL B CHANNEL 1
D CHANNEL
I. 430 OR I. 431
1.430 OR 1.431 -
SIGNALLING FOR PACKET SWITCHED
ADDITIONAL PACKET SWITCHED
CIRCUIT SWITCH ED SIGNALLING AND
SIGNALLING SIGNALLING AND
ACCESS
INFORMATION
FOR INCOMING INFORMATION
TRANSFER
PACKET CALLS TRANSFER
ADDITIONAL
SIGNALLING FOR
INCOMING PACKET
CALLS
NOTE - This protocol may not be present in all systems.
NOTE - These two protocols may not be present in all systems.
Figure 2 - Protocol layers at S and T reference points
Figure 3 - Protocol layers at S and T reference points
when D channel is used in iSDN when B channel is used in iSDN
4

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ISOAEC 9574 : 1989( E)
2.2.2.2 With call offering procedures
2.2 Additional procedures for a TE1 or TE2/TA
These additional procedures are used if the conditions in
to provide the CONS when using the ISDN D
1).
2.2.2.1 do not apply (see note
channel
IS0 8208 protocol procedures shall be used over the ISDN
layer 2 procedures using SAPLI 6. In addition the ISDN call
This clause is only applicable in case B access. TEls and
offering procedures are also operated over the ISDN layer 2
TE2/TAs supporting packet operation on the ISDN D channel
procedures, using either SAPLO or SAPL1 6. Systems
present a stack of protocols at the S or T reference point in
conformin to this International Standard, that operate these
accordance with the CClTT Recommendations indicated in
ISDN caf offerin rocedures, shall implement these
procedures using 8AbI=O and may also implement these
figure 2. At the physical layer, 1.430 shall be used if the ISDN
procedures using SAPLI 6 (see notes 2 and 3). The ISDN call
access is a basic interface and 1.431 shall be used if the ISDN
offering procedures (see notes 4 and 5) determine which TE1
access is a primary rate interface. At the data link layer, Q.921
or TE2/TA is to receive the call and are not visible to the NS
shall be used to provide the LAPD procedures. At the network
user. The IS0 8208 procedures are then operated after the
layer, IS0 8208 shall be used to provide the packet layer ISDN call offering procedures have been completed.
protocol and Q.931 may be used to provide the "call-offering
NOTES
procedure" which, when present, takes place before the
1 This includes when the interface to which the TE1 or TE2iTA is
connected has subscribed to the "Unconditional Notification class of
conveyance of X.25 INCOMING CALL packets. The Q.931
service",
procedures enable terminal identification (basic access) and
2 CClTTRecommendation X.31 states (note 4 to Section6.2.2.3.1).
a determination of which channel (D or B) a specific
"Networks providing packet mode call offerin shall provide Q.931
INCOMING CALL packet is to be conveyed on. The following
signalling procedures for packet mode calls on $PI=O. For an interim
limitations shall apply : period, some networks, b subscription agreement, may offer
SAPI=16 broadcast call ofiéring procedures for providing Q 931
signalling. This option will use all Q.931 procedures for packet mode
a) The maximum User Data field length of IS0 8208
calls with the following restriction: All calls will be offered as "D channel
DATA packets shall not exceed 256 octets.
exclusive" and will not rovide channel negotiation procedures.
Terminals implementing k!API=I6,, procedures shall also implement
b) The IS0 8208Throughput Class used shall not exceed
SAPI=O procedures for portability.
16 kbitdsec on a basic interface.
3 In order to maximise terminal portability during the interim period
identified in note 2, s stems should implement the call offering
The subscription and negotiated facilities in the X.25 Call §Ah=O and SAPI=16.
procedures on both
Establishment packets shall be used, as necessary, to indicate
4 These procedures may use Q.931 addressing, sub-addressing,
and com atibility checking information elements, to determine which
values consistent with these restrictions.
TE1 or ?&TA is to receive the call. In order to avoid unnecessary
connection failures, it is SU gested that incornin calls are not rejected
2.2.1 Outgoing calls on the basis of compatifility information udess this information
identifies as required, a functionality that the terminal is not capable
of (eg. a call should not be rejected because the HLC information
IS0 8208 procedures shall be operated over the ISDN layer
element is not present).
2 protocol using SAPL16 as defined in CClTT
5 These procedures may require D channel selection, or may offer
Recommendation X.31. No additional procedures are
the terminal a choice of D or B channels. No distinction is made here
required.
between these wa s of selecting the D channel. Subclause 2.3 covers
the case where a b channel is selected.
NOTE - The address fields of the IS0 8208 packets contain
sub-networkaddresses that arevalid forthe ISDN (e.g. E.164forpublic 2.3 Additional procedures for a TE1 or TE2/TA
ISDNs, where a valid E.164 address could be Escape Code + X. 121
to provide the CONS when using the ISDN B
number. A network dependent prefix may also be required).
channel
TEls and TE2/TAs supporting packet operation on the ISDN
0 2.2.2 incoming caits
B channel present stacks of protocols at the S or T reference
point in accordance with the CCllT Recommendations
The procedures applying to incoming calls vary according to
indicated in figure 3. One stack, which may be null, is used to
whether the ISDN call offering procedures are used.
sup ort signallin on SAPLO for circuit switched access to the
pacRet handling function and the 'call offering procedure', and
NOTE - The address fields of the IS0 8208 packets contain
the other is used to support packet switched si nalling and
sub-network addresses that are valid for the ISDN.
information transfer. At the physical layer, 1.430 s a all be used
if the ISDN access is
...