ISO/IEC TR 8802-1:1997
(Main)Information technology — Telecommunications and information exchange between systems — Local and metropolitan area networks — Specific requirements — Part 1: Overview of Local Area Network Standards
Information technology — Telecommunications and information exchange between systems — Local and metropolitan area networks — Specific requirements — Part 1: Overview of Local Area Network Standards
Technologies de l'information — Télécommunications et échange d'information entre systèmes — Réseaux locaux et métropolitains — Exigences spécifiques — Partie 1: Vue d'ensemble des normes de réseaux locaux
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ISO/IEC
TECHNICAL
TR 8802-I
REPORT
Second edition
1997-03-I 5
Information technology -
Telecommunications and information
exchange between systems - Local and
metropolitan area networks - Specific
requirements -
Part 1:
Overview of Local Area Network Standards
T6I&ommunications et &change
Technologies de /‘information -
R&eaux locaux et m&ropolitains -
d ‘informa tion en tre sys t&mes -
Exigences spkcifiques -
Partie 4: Vue d/ensemble des normes de rkseaux locaux
Reference number
lSO/IEC TR 8802-I :I 997(E)
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lSO/lEC TR 8802-l :1997(E)
Contents
1
1 Scope .
1
2 References .
3
............................................................................................................................................................
3 Abbreviations
3
............................................................................................................................
4 Local Area Network Technologies
3
............................................................................................................................................................
4.ll Introduction
4
..........................................................................................................................................
4.2 The LAN Technologies
4
4.2.1 CSMAICD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .~.
5
Token-passing Bus .
4.2.2
5
............................................................................................................................................
4.2.3 Token-passing Ring
5
...............................................................................................................................
4.2.4 Distributed Queue Dual Bus
5
..................................................................................................................................................
4.2.5 Demand Priority
6
......................................................................................................................
4.2.6 Integrated Services LAN Interface
6
4.2.7 Fibre Distributed Data interface .
6
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.3 Cabling Aspects
6
5 Data Link Layer *.,.,.,.,~.
6
5.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ‘.~.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
5.2 Provision and Support of the Data Link Layer Service
7
Sublayer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6 Medium Access Control
7
6.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .~. 7
6.2 Provision and Support of the MAC Service
7
6.2.1 Connectionless-mode Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .*.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
6.2.2 Acknowledged Connectionless-mode Service
8
6.3 48-Bit MAC Address Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8
6.4 Standard Group MAC Addresses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
0 ISOAEC 1997
All rights reserved. Unless otherwise specified, 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.
ISOAEC Copyright Off ice l Case postale 56 l Cl-l-1 211 Gen&ve 20 l Switzerland
Printed in Switzerland
ii
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................................................................................................................................... 8
7 Logical Link Control Sublayer
........................................................................................................... 0
7.1 Provision and Support of the LLC Services
.................................................................................................... 9
7.1 .l LLC Type 1 Connectionless-mode Operation
9
...........................................................................................................
7.1.2 LLC Type 2 Connection-mode Operation
9
7.1.3 LLC Type 3 Acknowledged Connectionless-mode Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .~. 9
7.2 Logical Link Control Addresses
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .*. 10
8 Internetworking
10
8.1 Transparent Bridging .
10
8.2 Source Routing .
10
8.3 Source Routing Transparent Architecture .
............................................................................................................................................ 10
9 System Load Protocol
................................................................................................................................... 11
10 The Use of PICS Proforma
......................................................................................................................................................... 11
11 Management
................................................................ 12
Annex A The Numbering Scheme for LAN/MAN International Standards
. . .
III
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Foreword
IS0 (the International Organization for Standardization) and IEC (the International
Electrotechnical Committee) form the specialized system for worldwide standardization. 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,
ISOAEC JTC 1.
The main task of technical committees is to prepare International Standards, but in exceptional
circumstances a technical committee may propose the publication of a Technical Report of one
of the following types:
- type 1, when the required support cannot be obtained for the publication of an International
Standard, despite repeated efforts;
- type 2, when the subject is still under technical development or where for any other reason
there is the future but not immediate possibility of an agreement on an International
Standard;
- type 3, when a technical committee has collected data of a different kind from that which is
normally published as an International Standard (“state of the art ”, for example).
Technical Reports of types 1 and 2 are subject to review within three years of publication, to
decide whether they can be transformed into International Standards. Technical Reports of
type 3 do not necessarily have to be reviewed until data they provide are considered to be no
longer valid or useful.
ISOAEC TR 8802-1, which is a Technical Report of type 3, was prepared by Joint Technical
Committee ISOAEC JTC 1, information technology, Subcommittee SC 6, Telecommunications
and information exchange between systems.
1
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Introduction
This Technical Report introduces the set of International Standards produced to facilitate the
interconnection of information processing systems connected to a Local Area Network (LAN).
The LAN is a peer-to-peer communications network provided by a single broadcast domain that
enables all end stations to exchange information. As a consequence it does not inherently
provide privacy. A LAN is in general owned, used, and operated by a single organisation and
falls within a single administrative domain.
This Technical Report provides a source of reference to all International Standards that relate to
local area networks; specifically the ISOAEC 8802 technologies and FDDI.
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TECHNICAL REPORT o ISO/IEC lSO/IEC TR 8802-l :1997(E)
Telecommunications and information
Information technology -
- Local and metropolitan area
exchange between systems
- Specific requirements - Part 1: Overview of Local
networks
Area Network Standards
1 Scope
This Technical Report provides an introduction to the set of International Standards which describe local area
networks, specifically those which make use of the 48-bit address format.
The technologies described in this Technical Report have in common the ability to provide sufficient capability to
support the MAC Service which is defined in ISO/IEC 15802-l.
The scope of this Technical Report is therefore limited to those International Standards which describe processes
and procedures resident in the Data Link and Physical Layers of the OSI Basic Reference Model and can be said to
relate to local area networks
This Technical Report does not itself describe new Service or Protocol definitions. Its intent is to set the context for
local area networks which include both the International Standards describing FDDI and the technologies described
by the set of ISO/IEC 8802 International Standards.
2 References
It was agreed in October 1993 to revise the existing numbering scheme of LAN/MAN International Standards within
NOTE
ISO/IEC JTC 1 to provide alignment with the numbering scheme used by IEEE for their LAN/MAN Standards. The process of
introducing the new scheme for new International Standards and the renumbering of existing International Standards is
on-going. Annex A describes the new numbering scheme in detail and indicates how its implementation will proceed.
ISO/IEC 7498-l : 1994, Information technology - Open Systems Interconnection - Basic Reference Model: The
Basic Model.
IS0 7498-3: 1989, Information processing systems - Open Systems Interconnection - Par? 3: Naming and
addressing.
ISO/IEC 8802-2: 1994, Information technology - Telecommunications and information exchange between systems
- Local and metropolitan area networks - Specific requirements - Par? 2: Logical link control.
ISO/IEC 8802-3: 1996, information technology - Telecommunications and information exchange between systems
- Local and metropolitan area networks - Specific requirements - Part 3: Carrier sense multiple access with
collision detection (CSMAKD) access method and physical layer specifications.
ISO/IEC 8802-4: 1990, Information processing systems - Local area networks - Part 4: Token-passing bus access
method and physical layer specifications.
ISO/IEC 8802-5: 1995, information technology - Local and metropolitan area networks - Specific requirements -
Part 5: Token ring access method and physical layer specifications.
ISO/IEC 8802-6: 1994, information technology - Local and metropolitan area networks - Specific requirements -
Part 6 Distributed Queue Dual Bus (DQDB) access method and physical layer specifications.
ISO/IEC 8802-g: 1996, information technology - Local and metropolitan area networks - Specific requirements -
Part 9: Integrated Services (IS) LAN Interface at the Medium Access Control (MAC) and Physical (PHY) Layers.
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lSO/lEC TR 8802-l :1997(E)
ISOAEC 8802-I 2:- 1 ) , information technology - Local and metropolitan area networks - Specific requirements -
Part 12: Demand priority access method, physical layer and repeater specifications.
ISOAEC 8886: 1996 I ITU-T Recommendation X.212 (1995), information technology - Open Systems
Interconnection - Data link service definition.
IS0 9314-l : 1989, information processing systems - Fibre Distributed Data Interface (FDDI) - Part I: Token Ring
Physical Layer Protocol (PHY).
IS0 9314-2: 1989, information processing systems - Fibre Distributed Data Interface (FDDI) - Part 2: Token Ring
Media Access Control (MAC).
ISOAEC 9314-3: 1990, information processing systems - Fibre Distributed Data Interface (FDDI) - Part 3: Physical
Layer Medium Dependent (PMD).
ISOAEC 931406:- I) , Information technology - Fibre Distributed Data Interface (FDDI) - Part 6: Station
Management (SMT).
ISOAEC TR 9577: 1996, Information technology - Protocol identification in the network layer.
ISOAEC 10038: 1993, Information technology - Telecommunications and information exchange between systems -
Local area networks - Media access control (MAC) bridges. (In the future to be published as ISOAEC 15802-3.)
ISOAEC 10165-4: 1992, information technology - Open Systems Interconnection - Structure of management
information - Part 4: Guidelines for the definition of management objects.
ISOAEC 10742: 1994, information technology - Telecommunications and information exchange between systems -
Elements of management information related to OS/ Data Link Layer standards.
ISOAEC 11575: 1995, information technology - Telecommunications and information exchange between systems -
Provision and mappings for the OS/ Data Link service.
ISOAEC 11801: 1995, information technology - Generic cabling for customer premises.
Telecommunications and information exchange between
ISOAEC TR 11802-I : 1997, information technology -
- Technical reports and guidelines - Part I: The structure and
systems - Local and metropolitan area networks
coding of Logical Link Control addresses in Local Area Networks. (Formerly published as ISOAEC TR 10178.)
ISOAEC TR 11802-2: 1996, information technology - Telecommunications and information exchange between
systems - Local and metropolitan area networks - Technical reports and guidelines - Part 2: Standard Group MAC
Addresses. (Formerly published as ISOAEC TR 10735.)
ISOAEC 15802-l : 1995, Information technology - Telecommunications and information exchange between systems
- Local and metropolitan area networks - Common specifications - Part 1: Medium Access Control (MAC) service
definition. (Formerly published as ISOAEC 10039.)
ISO/I EC 15802-4: 1994, Information technology - Telecommunications and information exchange between systems
- Local and metropolitan area networks - Common specifications - Part 4: System load protocol.
15802-5:
ISOA EC -I 1, Information technology - Te/ecommunica tions and information exchange between systems -
Local and metropolitan area networks - Common specifications - Part 5: Remote MAC bridging.
1) To be published.
2
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3 Abbreviations
The following abbreviations are used in this Technical Report.
Carrier Sense Multiple Access with Collision Detection
CSMAKD
Data Link Service
DLS
Distributed Queue Dual Bus
DQDB
Destination Service Access Point
DSAP
FDDI Fibre Distributed Data Interface
LAN Local Area Network
Logical Link Control
LLC
Media Access Control
MAC
Metropolitan Area Network
MAN
MCS Management Conformance Summary
MICS Management Information Conformance Statement
MOCS Managed Object Conformance Statement
Managed Relationship Conformance Statement
MRCS
PHY Physical Layer
PIGS Protocol Implementation Conformance Statement
PMD Physical Layer Medium Dependent
Station Management
SMT
SNAP Sub-network Access Protocol
SSAP Source Service Access Point
4 ILocaD Area Network Technologies
4.1 Introduction
The local area network technologies considered in this Technical Report are shown in Table 1.
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Table 1 - Local area network technologies and their related International Standards
LAN Technology Data Transmission Rate International Standard
I
1 OMbWs / 1 OOMbit/s ISO/I EC 8802-3
CSMAICD
I
5Mbit/s / 1 OMbit/s ISO/I EC 8802-4
Token-passing Bus
I
Token-passing Ring 4Mbit/s / 1 GMbit/s ISO/IEC 8802-5
I
1 no upper limit defined 1 ISO/IEC 8802-6
r-P Demand Priority 1 iOOMbit/s ( ISO/IEC 8802-12
up to 20.48Mbit/s ISO/I EC 8802-9
Integrated Services
I
1 OOMbit/s ISO/IEC 9314 -1 -2 -3 (-6)
FDDI
I
These International Standards are organised along the architectural lines of the OSI Basic Reference model, and in
the case of the 8802 LANs into the medium-dependent aspects of the Physical Layer (PHY) and the formats and
protocols used by the particular media access control sublayer (MAC).
Figure 1 shows the relationship and dependencies of the various technologies within this overall architecture. This
family of International Standards deals with the physical and data link layers as defined by the Open Systems
Interconnection Reference Model. It comprises a set of medium access technologies and associated physical
media, each appropriate for particular applications or system objectives.
DATA
lSO/IEC 8802-2
LINK
LAYER
ISOnEc
ISOnEc IsonEc ISOnEc IsonEc
IsonEc
8802-I 2
8802-6 8802-9 9314
88023 8802-5
PHYSICAL
LAYER
t
i r
- Relationship of family of International Standards for Local Area Networks
Figure 1
4.2 The LAN Technologies
LANs cover a wide variety of Physical Layer International Standards, physical media, and methods of media access
control. The following is a brief synopsis for each of the LAN technologies identified in Table 1, however the reader
is referred to the International Standard documents (see Clause 2) for the precise detail for each of the LAN
technologies.
4.2.1 CSMAKD
This form of LAN technology, Carrier Sense Multiple Access with Collision Detection, controls access to the medium
by means by which two or more stations share a common transmission medium. To transmit, a station waits
4
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(defers) for a quiet period on the medium (that is, no other station is transmitting) and then sends the intended
message in bit-serial form. If, after initiating a transmission, the message collides with that of another station, then
each transmitting station intentionally sends a few additional bytes to ensure propagation of the collision throughout
the system. The station then remains silent for a random amount of time (backoff) before attempting to transmit
again. The CSMA/CD LAN technology is defined for use on 50 ohm coaxial cable (lOBASE and lOBASE2), on
unshielded twisted pair (1 OBASE-T), and on fibre optic cable (FOIRL and 1 OBASE-F). lOOBASE-T couples the
ISO/IEC 8802-3 CSMA/CD MAC with a family of 100 Mbit/s physical layers. While the MAC is readily scaled to the
new performance levels, new physical layer standards are required for 100 Mbit/s operation and these include
1 OOBASE-T4,l OOBASE-TX and 1 OOBASE-FX.
4.2.2 Token-passing Bus
This form of LAN technology controls access to the medium through the use of a bus transmitted token which
allows the holder to transmit information onto the bus. The token bus LAN technology is defined for use on
broadband coaxial cable, on baseband coaxial cable, and on fibre optic cable.
4.2.3 Token-passing Ring
In a token-passing ring, stations are serially connected to form a logical ring over which data and control information
is transmitted and received.
referred
Access to this ring is controlled by a signalling sequence to as the “to ken” which circulates around the ring
from station to station.
A station desiring to transmit waits until it receives a token. The station changes the token to a start-of-message,
transmits its message and, upon completion of the message, releases a new token for use by other stations on the
ring.
Token ring is defined for operation on shielded and unshielded twisted pair medium at data rates of 4 and 16 Mbit/s.
In addition, token ring may operate using fibre optic cable.
4.2.4 Distributed Queue Dual Bus
DQDB is defined to have the capability to work over the local area and to interoperate with the other local area
network technologies. In particular DQDB has the capability to use the 48-bit MAC address format and for that
reason it is included in this Overview.
However, DQDB is more often encountered in the Metropolitan Area and it introduces the concept of the
Metropolitan Area Network (MAN) where the development of a high speed technology to support connectionless
data services is required. Because of the differing environments in which the DQDB MAN will be utilised, a variety of
Physical Layer protocols are required. Physical Layer protocols which make use of existing underlying transmission
standards have been defined. However it is intended that all Physical Layer specifications (PHY) will be based upon
a common framework.
4.2.5 Demand Priority
A Demand Priority LAN comprises three principal components; the end nodes, the repeaters, and the network links.
End nodes are typically personal or larger computers but may be special devices, for example bridges. Repeaters
are the network controllers which manage the Demand Priority Access Method. The link segments provide the
interconnection between a repeater and its connected end nodes or other repeaters.
Demand priority access is a priority-based, round-robin arbitration method where the central network controller (the
repeater) regularly polls its connected ports to determine which have transmission requests pending, and whether
the transmission request is normal priority (e.g. for data files) or high priority (e.g. for real time voice, video or data).
The medium access protocol provides a means by which stations (end nodes) can communicate with each other
over a centrally controlled LAN that offers a choice of several different link media including 100 Ohm balanced cable
(4.UTP and 2=TP), 150 Ohm shielded balanced cable (STP), and optical fibre.
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4.2.6 Integrated Services LAN interface
The ISLAN interface is an integrated voice, data and video interface that provides packet service and isochronous
digital channels on a full duplex interface to the desktop over unshielded telephone twisted pairs (UTP). The
integrated service is provided to the terminal equipment across an interface called an access unit (AU). The AU
accommodates two fundamentally different application topologies; firstly the interface may be to a stand-alone LAN
where the AU provides the complete pathway; and secondly the ISLAN serves as an access interface that feeds
into a backbone comprising an lSO/IEC 8802-x LAN, an FDDI, or an integrated services digital network.
The connection between the AU and the terminal equipment is a set of point-to-point links in a star topology. Carried
wideband data and other services such as
over these links is a multiplexed bit stream of packet data, voice,
facsimile, image or video delivered over isochronous channels.
This specification is capable of supporting information transfer rates that are multiples of 4.096 Mbit/s in
isochronous frames delivered at 8 kHz with specifications provided for the use of 4.096 Mbit/s and 20.48 Mbit/s time
division multiplexed bearers with 64 and 320 slots each comprising one octet.
4.2.7 Fibre Distributed Data Interface
The Physical Medium Dependent (PMD) provides the digital baseband channel for point to point communication
between nodes on the FDDI network, It provides all services necessary to transport a suitably coded digital bit
stream. The specific definition and characterisation may be found in ISO/IEC 9314-3.
The Physical Layer Protocol (PHY) provides the connection between the PMD and the Data Link Layer (the MAC).
It provides clock synchronisation with the upstream data stream and provides the encoding and decoding of
symbols, and the delineation of symbol boundaries as required for the transmission of information to or from higher
layers. The specific definitions and characterisations may be found in IS0 9314-1.
4.3 Cabling Aspects
For the implementation of the LAN applications mentioned in Table 1, an application independent solution has been
developed in ISO/IEC 11801. The document provides for the generic cabling of customer premises, supporting all
major applications. The specific definitions and characterisations may be found in this document.
5 Data Link Layer
5.1 Introduction
For the specification of ISO/IEC 8802 Local Area Networks, the separation of the Data Link Layer of the OSI Basic
Reference Model into two sublayers is of benefit. The Data Link Layer is therefore refined to show a Logical Link
Control Sublayer and a Medium Access Control Sublayer.
5.2 Provision and Support of the Data Link Layer Service
ISO/IEC 8886 I IT&T Recommendation X.212 contains the generic Data Link Service (DLS) definition for OSI and,
as such, the elements of service definition within LLC can be regarded as a subset of this generic service definition.
The OSI DLS definition describes the properties of individual instances of Data Link communication between pairs
of DLS users. It is expressed abstractly in terms of primitives and parameters exchanged, at the Data Link service
access points, between each DLS user and a single DLS provider. In this respect the service definition contained in
LLC is no different.
ISO/IEC 11575 seeks to unify the generic DLS definition with the specific instances of Data Link layer service, e.g.
LLC, and includes mapping the OSI DLS for LLC Types 1 and 2. The fundamental objective is to achieve such a
mapping without requiring any change to the protocols themselves; further it is specifically not the intent to restrict
the development of new protocols. It accepts that the service definitions contained in ISO/IEC 8802-2 for LLC Types
1 and 2 while performing a similar function to the OSI DLS differ in some points of detail. It attempts to identify
places where there is a possible impact of mapping the DLS to the text of ISO/IEC 8802-2 and to indicate how the
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text would need to change if the DLS mapping were to be incorporated into ISO/IEC 8802-2 as a replacement for
the existing LLC service definition.
6 Medium Access Control Sublayer
6.1 Introduction
The development of the concepts associated with the MAC sublayer have been intimately related to the
development of the different LAN technologies. Indeed each LAN Standard describes the MAC S
...
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