SIST ETS 300 211 E1:2003

Network Aspects (NA); Metropolitan Area Network (MAN); Principles and architecture

DE/NA-053020

Omrežni vidiki (NA) – Velemestno omrežje (MAN) – Načela in arhitektura

General Information

• Status: Published
• Publication Date: 30-Nov-2003
• ICS: 35.110 - Networking
• Technical Committee: SS EIT - Technical Board for the electrotechnical, information technology and telecommunications fields
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 01-Dec-2003
• Due Date: 01-Dec-2003
• Completion Date: 01-Dec-2003
• Ref Project: ETSI ETS 300 211 ed.1 (1992-12) - Network Aspects (NA); Metropolitan Area Network (MAN); Principles and architecture

Standards Content (Sample)

SLOVENSKI STANDARD
SIST ETS 300 211 E1:2003
01-december-2003
2PUHåQLYLGLNL1$±9HOHPHVWQRRPUHåMH0$1±1DþHODLQDUKLWHNWXUD
Network Aspects (NA); Metropolitan Area Network (MAN); Principles and architecture
Ta slovenski standard je istoveten z: ETS 300 211 Edition 1
ICS:
35.110 Omreževanje Networking
SIST ETS 300 211 E1:2003 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST ETS 300 211 E1:2003

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SIST ETS 300 211 E1:2003
EUROPEAN ETS 300 211
TELECOMMUNICATION December 1992
STANDARD
Source: ETSI TC-NA Reference: DE/NA-053020
ICS: 33.040
Key words: Network, MAN, principles
Network Aspects (NA);
Metropolitan Area Network (MAN)
Principles and architecture
ETSI
European Telecommunications Standards Institute
ETSI Secretariat
Postal address: F-06921 Sophia Antipolis CEDEX - FRANCE
Office address: 650 Route des Lucioles - Sophia Antipolis - Valbonne - FRANCE
X.400: c=fr, a=atlas, p=etsi, s=secretariat - Internet: [e-mail]
Tel.: [phone] - Fax: [phone]
Copyright Notification: No part may be reproduced except as authorized by written permission. The copyright and the
foregoing restriction extend to reproduction in all media.
© European Telecommunications Standards Institute 1992. All rights reserved.

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ETS 300 211: December 1992
Whilst every care has been taken in the preparation and publication of this document, errors in content,
typographical or otherwise, may occur. If you have comments concerning its accuracy, please write to
"ETSI Editing and Committee Support Dept." at the address shown on the title page.

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Contents
Foreword .5
1 Scope .7
2 Normative references.7
3 Definitions and abbreviations .9
3.1 Definitions .9
3.1.1 Interfaces.9
3.1.2 Network elements.9
3.1.3 Functions.10
3.1.4 Services.10
3.2 Alphabetical list of terms.11
3.3 Abbreviations .11
4 Basic principles .14
5 Functional architecture.16
5.1 General architecture .16
5.2 Reference configuration and functions .19
5.2.1 Reference points .19
5.2.2 List of functional groups .19
5.2.3 List of functions .21
5.3 Access Facilities (AFs) .23
5.3.1 Access facility 1 (AF1).23
5.3.2 Access Facility 2 (AF2).24
5.3.2.1 User Specific Interfaces (USIs) .25
5.3.2.1.1 USI based on ISO/IEC 8802-3 (CSMA/CD) .25
5.3.2.1.2 USI based on ISO/IEC 8802-5 (Token Ring).26
6 Protocol reference model for MANs.34
6.1 Generic reference model .34
6.2 Protocol reference model.34
6.3 Extension of the MAN PRM to accommodate encapsulation of MAC-PDUs containing
48 bit addresses.35
6.4 Application of the PRM for Access Facility 1 .36
6.5 Application of the PRM for Access Facility 2 .36
6.5.1 Application of the PRM for Access Facility 2a.36
6.5.2 Application of the PRM for Access Facility 2b.37
7 Addressing principles .43
7.1 Individual addresses .43
7.2 Group addresses .43
8 MAN management .43
8.1 MAN management framework.43
8.2 Generic MAN management functional architecture.44
Annex A (informative): MAN Switching System (MSS) .45
A.1 MSS management functions.45
A.2 Control & switching functions .45
A.3 DQDB access termination.45

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A.4 Transit access termination. 45
A.5 DQDB access termination configurations. 46
Annex B (informative): Bibliography . 49
History. 50

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Foreword
This European Telecommunication Standard (ETS) has been prepared by the Network Aspects (NA)
Technical Committee of the European Telecommunications Standards Institute (ETSI).
This ETS describes the basic principles of the European Metropolitan Area Network (MAN) concept and is
elaborated, taking into account the following:
- the emerging demand for multi-megabit communication services, especially for business users;
- the availability of new network technology based on distributed access over a shared broadband
medium;
- the strategic need that the development and introduction of MAN products in Europe be driven by
adequate ETSI standards;
- the requirement that MAN standardisation takes into account ongoing standardisation work on
Broadband Integrated Services Digital Network (B-ISDN) and generate the necessary output so as
to influence B-ISDN development.
MANs will promote B-ISDN by enabling network operators to timely offer a subset of B-ISDN services; in
this way, user demand and provision of MANs should provide a graceful evolution towards B-ISDN by
facilitating the access to this network.
The description of interworking aspects between the MAN and the transit network will be provided in the
relevant ETSI documents.
General aspects of MAN management are defined in this ETS. More detailed information will be provided
in the relevant ETSI documents.

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1 Scope
This European Telecommunication Standard (ETS) describes the basic principles and network
architecture for an European Metropolitan Area Network (MAN).
This ETS defines and describes the MAN reference configuration and the functional blocks between the
Customer Network (CN) and the MAN Switching System (MSS), which is described in Annex A
(informative).
In addition, this ETS defines the protocol reference model for MANs, and is the basis for the development
of companion ETSs related to MAN protocols (ETS 300 212 to ETS 300 216, [19] to [23], inclusive).
General aspects of MAN management are also defined in this ETS.
The MAN definition takes into account the final goal of providing an easy integration with Broadband
Integrated Services Digital Network (B-ISDN).
The protocol chosen as the basis for this ETS is the IEEE Standard 802.6 [1].
The specification of performance figures is outside the scope of this ETS.
2 Normative references
This ETS incorporates, by dated or undated reference, provisions from other publications. These
normative references are cited at the appropriate places in the text and the publications are listed
hereafter. For dated references, subsequent amendments to, or revisions of any of these publications
apply to this ETS only when incorporated in it by amendment or revision. For undated references the latest
edition of the publication referred to applies.
[1] IEEE Standard 802.6 (1990): "Distributed Queue Dual Bus (DQDB) Subnetwork
of a metropolitan area network (MAN)".
[2] CCITT Recommendation I.431 (1988): "Primary rate user-network interface -
Layer 1 specification".
[3] CCITT Recommendation M.30 (1989): "Principles for a telecommunications
management network".
[4] CCITT Recommendation X.200 (1988): "Reference model of open systems
interconnection for CCITT applications".
[5] CCITT Recommendation I.113 (1991): "Vocabulary of terms for broadband
aspects of ISDN".
[6] CCITT Recommendation I.121 (1991): "Broadband aspects of ISDN".
[7] CCITT Recommendation I.150 (1991): "B-ISDN asynchronous transfer mode
functional characteristics".
[8] CCITT Recommendation I.211 (1991): "B-ISDN service aspects".
[9] CCITT Recommendation I.311 (1991): "B-ISDN general network aspects".
[10] CCITT Recommendation I.321 (1991): "B-ISDN protocol reference model and
its application".
[11] CCITT Recommendation I.327 (1991): "B-ISDN functional architecture".
[12] CCITT Recommendation I.361 (1991): "B-ISDN ATM layer specification".
[13] CCITT Recommendation I.362 (1991): "B-ISDN ATM adaptation layer (AAL)
functional description".

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[14] CCITT Recommendation I.363 (1991): "B-ISDN ATM adaptation layer (AAL)
specification".
[15] CCITT Recommendation I.413 (1991): "B-ISDN user network interface".
[16] CCITT Recommendation I.432 (1991): "B-ISDN user network interface Physical
layer specification".
[17] CCITT Recommendation I.610 (1991): "OAM principles of the B-ISDN access".
[18] ISO/IEC 10038: "Information technology - Telecommunications and information
exchange between systems - Local area network - Media access control (MAC)
bridges".
[19] ETS 300 212 (1992): "Network Aspects (NA); Metropolitan Area Network (MAN)
Media access control layer and physical layer specification".
[20] ETS 300 213 (1992): "Network Aspects (NA); Metropolitan Area Network (MAN)
Physical layer convergence procedure for 2,048 Mbit/s".
[21] ETS 300 214 (1992): "Network Aspects (NA); Metropolitan Area Network (MAN)
Physical layer convergence procedure for 34,368 Mbit/s".
[22] ETS 300 215 (1992): "Network Aspects (NA); Metropolitan Area Network (MAN)
Physical layer convergence procedure for 139,264 Mbit/s".
[23] ETS 300 216 (1992): "Network Aspects (NA); Metropolitan Area Network (MAN)
Physical layer convergence procedure for 155,520 Mbit/s".
[24] ETS 300 217, Parts 1 to 4 (1992): "Network Aspects (NA); Connectionless
Broadband Data Service (CBDS)".
[25] ISO/IEC 8802-3 (1990): "Information processing systems - Local area networks
- Part 3: Carrier sense multiple access with collision detection (CSMA/CD)
access method and physical layer specifications".
[26] ISO/IEC 8802-5 (1992): "Information processing systems - Local and
metropolitan area networks - Part 5: Token ring access method and physical
layer specifications".
[27] IEEE Standard 802.3b (1988): "Broadband Medium Attachment Unit and
Broadband Medium Specifications, Type 10 BROAD36".
[28] IEEE Standard 802.3i (1990) (supplement to 802.3, (1990) edition): "System
Considerations for Multi-Segment 10MB/S Baseband Networks (Section 13) and
Medium Attachment Unit and Baseband Medium specification, Type 10 Base-T
(Section 14)".
[29] IEEE Standard 802.1 (1990): "Local Area Network and Metropolitan Area
Network - Overview and architecture".
[30] CCITT Recommendation E.164 (1991): "Numbering plan for the ISDN era".
[31] CCITT X.700 Recommendation Series (1988) on System management.
[32] CCITT Recommendation I.411 (1988): "ISDN user-network interfaces -
Reference configurations".
[33] CCITT Recommendation I.320 (1988): "ISDN protocol reference model".
[34] ISO 9314 (1989): "Information processing systems - Fiber Distributed Data
Interface (FDDI)".

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[35] prETS 300 273: "Network Aspects (NA); Metropolitan Area Network (MAN)
Medium Access Control (MAC) layer management".
[36] prETS 300 275: "Network Aspects (NA); Metropolitan Area Network (MAN)
Interconnection of MANs".
[37] prETS 300 276: "Network Aspects (NA); Metropolitan Area Network (MAN)
Physical layer convergence procedure for 622,080 Mbit/s CCITT
Recommendations G.707, G.708 and G.709 SHD based systems".
[38] prETS 300 268: "Network Aspects (NA); Metropolitan Area Network (MAN)
Protocol Implementation Conformance Statement (PICS)".
[39] ISO/IEC TR 9575 (1990): "Information technology - Telecommunications and
information exchange between systems - OSI Routing Framework".
[40] CCITT Recommendation G.773 (1990): "Protocol suites for Q-interfaces for
management of transmission systems".
3 Definitions and abbreviations
This Clause consists primarily of those terms and definitions that are considered essential to the
understanding and application of the principles of MANs.
3.1 Definitions
For the purposes of this ETS, the following definitions apply.
3.1.1 Interfaces
101 Inter MAN Systems Interface (IMSI) : IMSI is a generic term that correspond to a family of
interfaces. These interfaces apply between two MSSs or between the MSS and the Transit
Network. As far as the direct interconnection between MSSs is concern, corresponding
interfaces are described in ETS 300 275 [36], the specification of the interconnection via
Asynchronous Transfer Mode (ATM) links will be provided in another ETSI document.
102 User MAN Interface (UMI): interface between the CN and the Access Facility 1 (AF1).
103 User Specific Interface (USI): interface based on a user specific protocol.
3.1.2 Network elements
201 Shared medium: transmission facility whose capacity is shared among several users.
202 Access Node (AN): the network element located in the Customer EQuipment (CEQ) which
performs the interfacing of various customer related protocols with the Distributed Queue
Dual Bus (DQDB) protocol.
203 Terminal Equipment (TE): user terminals. The term "terminal" is used in a broad sense with
different levels of complexity and functionality.
204 Customer Network (CN): the CN is defined between the T and S reference points.
M M
205 Customer EQuipment (CEQ): the concatenation of equipment on the user side of the T
M
reference point. In the case of multiple access, the CEQ includes all the equipment on the
user side of all those accesses comprising the multiple access.
206 Access Facility (AF): the network segment that connects the CN to the MAN Switching
System (MSS). The functionality of the AF may vary.
207 Access Facility 1 (AF1): an AF which only consists of a DQDB link between the CEQ and
the MSS.

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208 Access Facility 2 (AF2): an AF which consists of a gathering network.
209 Gathering network: a network which consists of several interconnected public MAN nodes.
210 Metropolitan Area Network (MAN): digital network based on a shared access broadband
medium. A MAN covers an urban or metropolitan area (typically in the range of 50 km in
diameter). A MAN is composed of one MSS and one or more AFs connected to the MSS.
Remote MANs can be interconnected in order to cover a larger area by means of public
Transit Network (TN) facilities. A MAN is a means to provide the support of narrowband and
broadband services integrated in the same network.
211 MAN Switching System (MSS): a collection of functions that provides high-speed switching
in the public network. It can be implemented through distributed or centralised switching.
212 MAN Node (MN): a network element, located in the public domain, performing the interfacing
between the CEQ and the IEEE Standard 802.6 [1] DQDB protocol.
213 Transit Network (TN) : a network which provides transmission, switching and management
functions to allow MSS interconnection. It can be implemented through point-to-point links,
digital cross-connect, B-ISDN transit node, etc.
3.1.3 Functions
301 DQDB Access Functions (DAF): protocol functions required to receive and transmit
information over the shared medium between different nodes. Functions for the management
of the DQDB subnetwork are also contained in DAF.
302 DQDB Access Termination (DAT): functions within the MSS which consist of the DAF and
Service Specific Function (SSF) functional blocks.
303 Service Specific Functions (SSF): those functions required for the provision of the
connectionless, connection-oriented isochronous and connection-oriented non-isochronous
services.
304 User Access Functions (UAF): the functionality to access a user specific network or a
directly attached terminal.
3.1.4 Services
401 Connectionless service: a service, supporting the transfer of variable length data units that
can tolerate variable delay but require error detection functions and without the establishment
of an end to end connection. This service is described in ETS 300 217 [24] and is
comparable to the "packet-oriented" Medium Access Control (MAC) service of ISO/IEC 8802
[25], Local Area Networks (LANs).
402 Connection-oriented isochronous service: a service which is oriented to the transport of
isochronous data (e.g. conventional digitised voice); "isochronous" means that the time
characteristic of an event or signal is recurring at known, periodic time intervals (as defined in
IEEE Standard 802.6 [1]). The precise definition of this service is outside the scope of this
ETS and is for further study.
403 Connection-oriented non-isochronous service: a service supporting the transfer, over a
virtual channel, of information flows segmented into fixed-length cells having no specified
inter-arrival time. The precise definition of this service is outside the scope of this document
and is for further study.

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3.2 Alphabetical list of terms
206 Access Facility (AF)
207 Access Facility 1 (AF1)
208 Access Facility 2 (AF2)
202 Access Node (AN)
402 Connection-oriented isochronous service
403 Connection-oriented non-isochronous service
401 Connectionless service
205 Customer EQuipment (CEQ)
204 Customer Network (CN)
301 DQDB Access Functions (DAF)
302 DQDB Access Termination (DAT)
209 Gathering network
101 Inter MAN systems Interface (IMSI)
210 Metropolitan Area Network (MAN)
212 MAN Node (MN)
211 MAN Switching System (MSS)
303 Service Specific Functions (SSF)
201 Shared medium
304 User Access Functions (UAF)
102 User MAN Interface (UMI)
103 User Specific Interface (USI)
203 Terminal Equipment (TE)
213 Transit Network (TN)
3.3 Abbreviations
For the purposes of this ETS, the following abbreviations apply:
ACF Access Control Field
AF Access Facility
AN Access Node
ATM Asynchronous Transfer Mode
AUI Attachment Unit Interface

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B-ISDN Broadband Integrated Services Digital Network
BT BiT sublayer
C&S Control & Switching functions
CEQ Customer EQuipment
CN Customer Network
CNMS Customer Network Management Services
CSMA/CD Carrier Sense Multiple Access with Collision Detection
DAF DQDB Access Functions
DAT DQDB Access Termination
DDI Direct Dialling In
DLSAP Data Link Service Access Point
DM Derived MAC sublayer
DM-PDU Derived MAC Protocol Data Unit
DQDB Distributed Queue Dual Bus
DTE Data Terminal Equipment
DXC Digital Cross-Connect
E-LAN Extended LAN
EOB End Of Bus
FDDI Fibre Distributed Data Interface
HL Higher Layers
HOB Head Of Bus
IM Initial MAC sublayer
IM-PDU Initial MAC-Protocol Data Unit
IMSI Inter MAN Systems Interface
ISPBX Integrated Services Private Branch eXchange
LAN Local Area Network
LCRF Local Connection Related Function
LLC Logical Link Control
LT Line Termination
M-LT MAN-Line Termination
M-NT MAN-Network Termination

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MAC Media Access Control
MAN Metropolitan Area Network
MAU Medium Attachment Unit
MDI Medium Dependent Interface
MIC Medium Interface Connector
MID Message IDentifier
MMF MSS Management Function
MN MAN Node
MS Management Services
MSAP MAC Service Access Point
MSS MAN Switching System
NMF Node Management Function
NT Network Termination
OSI Open Systems Intercommunication
OUI Organisationally Unique Identifier
PA Pre-Arbitrated
PID Protocol IDentifier
PHY PHYsical layer
PLS PhysicaL Signalling
PMA Physical Medium Attachment
PRM Protocol Reference Model
QA Queued Arbitrated
QOS Quality Of Service
SLT SLoT sublayer
SLT-PDU SLot Protocol Data Unit
SM SegMent sublayer
SM-PDU SegMent Protocol Data Unit
SNAP Sub-Network Access Protocol
SSF Service Specific Functions
SV SerVice sublayer
TAT Transit Access Termination

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TC Transmission Convergence sublayer
TCRF Transit Connection Related Function
TCU Trunk Coupling Unit
TE Terminal Equipment
TL Transit Link
TM TransMission sublayer
TMN Telecommunication Management Network
TN Transit Network
UAF User Access Functions
UMI User MAN Interface
USI User Specific Interface
4 Basic principles
A MAN is defined as a digital network that:
- is oriented to public domain network applications;
- is based on a shared access broadband medium;
- covers an urban or metropolitan area (typically in the range of 50 km in diameter);
- can be interconnected with other remote MANs in order to cover a larger area by means of public
transit network facilities, whose specification is outside the scope of this ETS;
and is a means to provide integrated support of narrowband and broadband services (data, voice, video)
as supported by bearer services e.g.:
- connectionless service;
a service, supporting the transfer of variable length data units that can tolerate variable delay but
require error detection functions and without the establishment of an end-to-end connection. This
service is described in ETS 300 217 [24] and is comparable to the "packet oriented" MAC service of
ISO/IEC 8802 [25], Local Area Networks (LANs);
- connection-oriented isochronous service;
a service which is oriented to the transport of isochronous data; "isochronous" means that the time
characteristic of an event or signal is recurring at known, periodic time intervals (as defined in IEEE
Standard 802.6 [1]). The precise definition and description of this service and the way to support it
are outside the scope of this ETS and are for further study;
- connection-oriented non-isochronous service;
a service, supporting the transfer, over a virtual channel, of information flows segmented into fixed-
length cells that have no specified inter-arrival time. The precise definition and description of this
service and the way to support it in a MAN are outside the scope of this ETS and are for further
study.

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A MAN is oriented to public domain network applications, and is devoted to a multi-user environment. The
same basic technologies and architectures can be used in a private environment, as CNs that are
identified with the term "Extended LANs" (E-LANs), but the differences in operational and management
attributes are substantial.
The field of application of MANs is primarily directed towards large business users.
MAN solutions are intended, in a first phase, mainly for carrying data services, in particular for the
interconnection of LANs with resulting service characteristics comparable with those available within a
single LAN, mainly in terms of throughput and delay.
As far as the isochronous services are concerned, the provision of primary rate access (CCITT
Recommendation I.431 [2]), suitable e.g. for the interconnection of Integrated Services Private Branch
eXchanges (ISPBXs), is considered to be of primary interest.
MANs are digital networks based on a shared access broadband medium: a broadband transmission
medium (e.g. optical fibre) is shared by network nodes under the control of a distributed multiple access
protocol.
MANs play the role of public access/gathering networks to provide multi-megabit communication services
to heterogeneous users, in particular to business customers.
With reference to the B-ISDN, the MAN concept is based on "distributed Local Connection Related
Functions (LCRF)": customers have access to the network using a shared medium.
The specificity of MANs may require, in some cases, the adoption of concepts and terminology other than
those up to now defined by B-ISDN. Additional concepts, terminology, reference configurations, functional
groups and reference points are required for MANs.
The IEEE Standard 802.6 [1] DQDB is the distributed multiple access protocol identified as the basis for
ETSI MANs, at least for connectionless services. This multiple access protocol is specified in ETS
300 212 [19].
However, where only two DQDB nodes are connected to a dual bus (simple point-to-point configuration) a
subset of the full IEEE Standard 802.6 [1] protocol may be implemented.
Simplifications applying in the special case are indicated in ETS 300 268 [38].
Enhancements to the IEEE Standard 802.6 [1] DQDB access method for the support of services with
guaranteed constant bit rate and specified transfer delay is defined in ETS 300 276 [37].
The MAN concept includes not only the transmission infrastructure and the access protocol but also the
necessary additional functions such as principles for network management and other operational issues,
as required in a multi-user environment.
MAN architecture is described in functional terms, and it is recognised that MANs may be implemented in
a variety of configurations according to specific situations.

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5 Functional architecture
5.1 General architecture
A MAN is composed of one MSS and one or more AFs connected to the MSS. The general architecture
for MANs is depicted in figure 1. The CNs are connected to AFs that terminate on MSSs. Several MSSs
are interconnected, through the TN, through Inter MAN Systems Interfaces (IMSIs).
At least two options are envisaged for the AFs, as shown in figure 2:
- the first, (AF1), is based on a distributed multiple access protocol with shared medium; the CEQ is
connected to this link through the UMI;
- the second one, (AF2), is based on a set of MNs, forming a gathering network; they communicate
through a distributed multi
...