SIST ES 282 001 V2.0.0:2008

Final draft ETSI ES 282 001 V2.0.0 (2007-11)
ETSI Standard


Telecommunications and Internet converged Services and
Protocols for Advanced Networking (TISPAN);
NGN Functional Architecture

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2 Final draft ETSI ES 282 001 V2.0.0 (2007-11)



Reference
RES/TISPAN-02046-NGN-R2
Keywords
architecture, functional
ETSI
650 Route des Lucioles
F-06921 Sophia Antipolis Cedex - FRANCE

Tel.: +33 4 92 94 42 00  Fax: +33 4 93 65 47 16

Siret N° 348 623 562 00017 - NAF 742 C
Association à but non lucratif enregistrée à la
Sous-Préfecture de Grasse (06) N° 7803/88

Important notice
Individual copies of the present document can be downloaded from:
http://www.etsi.org
The present document may be made available in more than one electronic version or in print. In any case of existing or
perceived difference in contents between such versions, the reference version is the Portable Document Format (PDF).
In case of dispute, the reference shall be the printing on ETSI printers of the PDF version kept on a specific network drive
within ETSI Secretariat.
Users of the present document should be aware that the document may be subject to revision or change of status.
Information on the current status of this and other ETSI documents is available at
http://portal.etsi.org/tb/status/status.asp
If you find errors in the present document, please send your comment to one of the following services:
http://portal.etsi.org/chaircor/ETSI_support.asp
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 2007.
All rights reserved.

TM TM TM
DECT , PLUGTESTS and UMTS are Trade Marks of ETSI registered for the benefit of its Members.
TM
TIPHON and the TIPHON logo are Trade Marks currently being registered by ETSI for the benefit of its Members.
TM
3GPP is a Trade Mark of ETSI registered for the benefit of its Members and of the 3GPP Organizational Partners.
ETSI

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3 Final draft ETSI ES 282 001 V2.0.0 (2007-11)
Contents
Intellectual Property Rights.5
Foreword.5
1 Scope.6
2 References.6
2.1 Normative references.6
3 Definitions and abbreviations.7
3.1 Definitions.7
3.2 Abbreviations.7
4 Overall architecture .9
5 Transport layer.10
5.1 Transport control sublayer.10
5.1.1 Network Attachment Subsystem (NASS).10
5.1.2 Resource and Admission Control Subsystem (RACS) .11
5.2 Transport processing functions.12
5.2.1 Border Gateway Function (BGF).13
5.2.1A Resource Control Enforcement Function (RCEF) .14
5.2.2 Void.14
5.2.3 Access Relay Function (ARF) .14
5.2.4 Media Gateway Function (MGF).14
5.2.5 Media Resource Function Processor (MRFP) .15
5.2.6 Signalling Gateway Function (SGF).15
5.2.7 Access Management Function (AMF).15
5.2.8 Basic Transport Function (BTF).15
5.2.8.1 Elementary Forwarding Function (EFF) .16
5.2.8.2 Elementary Control Function (ECF) .16
6 Service Layer Model .16
6.1 The "Core" IP Multimedia Subsystem (IMS).16
6.2 The PSTN/ISDN Emulation subsystem (PES).17
6.3 The IPTV Subsystem.17
6.4 Void.17
6.5 Common components.17
6.5.1 User Profile Server Function (UPSF) .18
6.5.2 Subscription Locator Function (SLF) .18
6.5.3 Application Server Function (ASF) .18
6.5.4 Void.18
6.5.5 Interworking Function (IWF) .18
6A Charging and Data Collection Functions .19
7 NGN Interconnection .19
7.1 General.19
7.2 Interconnection reference points and functions.19
7.2.1 Interconnection at the transport layer .19
7.2.1.1 Transport processing sublayer.19
7.2.1.2 NASS.20
7.2.1.3 RACS .20
7.2.2 Interconnection at the Service Layer .21
7.3 NGN Interconnection types.22
7.3.1 SoIx in the NGN Architecture .22
7.3.2 CoIx in the NGN Architecture.23
7.3.3 PSTN Interconnection types.24
7.3.4 NGN Direct and Indirect interconnection modes.25
8 User Equipment (UE).28
ETSI

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4 Final draft ETSI ES 282 001 V2.0.0 (2007-11)
8.1 Overview .28
8.2 Authentication.28
8.3 Reference points.29
8.3.1 Reference points to the core IMS.29
8.3.2 Reference points to the PSTN/ISDN Emulation subsystem .29
8.3.3 Reference points with applications .30
8.3.4 Reference points with the NASS .30
8.3.5 Reference points with the RACS .30
8.3.6 Reference points with transport processing functions.30
8.3.7 Reference points with access media gateway functions.30
Annex A (informative): Example of physical configuration for xDSL access.31
Annex B (informative): Transport architecture for multicast .32
B.1 Introduction.32
B.2 Multicast Functions in Transport Plane.32
History .34

ETSI

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5 Final draft ETSI ES 282 001 V2.0.0 (2007-11)
Intellectual Property Rights
IPRs essential or potentially essential to the present document may have been declared to ETSI. The information
pertaining to these essential IPRs, if any, is publicly available for ETSI members and non-members, and can be found
in ETSI SR 000 314: "Intellectual Property Rights (IPRs); Essential, or potentially Essential, IPRs notified to ETSI in
respect of ETSI standards", which is available from the ETSI Secretariat. Latest updates are available on the ETSI Web
server (http://webapp.etsi.org/IPR/home.asp).
Pursuant to the ETSI IPR Policy, no investigation, including IPR searches, has been carried out by ETSI. No guarantee
can be given as to the existence of other IPRs not referenced in ETSI SR 000 314 (or the updates on the ETSI Web
server) which are, or may be, or may become, essential to the present document.
Foreword
This ETSI Standard (ES) has been produced by ETSI Technical Committee Telecommunications and Internet
converged Services and Protocols for Advanced Networking (TISPAN), and is now submitted for the ETSI standards
Membership Approval Procedure.
ETSI

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6 Final draft ETSI ES 282 001 V2.0.0 (2007-11)
1 Scope
The present document describes the overall TISPAN NGN functional architecture, its subsystems and the relationships
between them.
2 References
References are either specific (identified by date of publication and/or edition number or version number) or
non-specific.
• For a specific reference, subsequent revisions do not apply.
• Non-specific reference may be made only to a complete document or a part thereof and only in the following
cases:
- if it is accepted that it will be possible to use all future changes of the referenced document for the
purposes of the referring document;
- for informative references.
Referenced documents which are not found to be publicly available in the expected location might be found at
http://docbox.etsi.org/Reference.
For online referenced documents, information sufficient to identify and locate the source shall be provided. Preferably,
the primary source of the referenced document should be cited, in order to ensure traceability. Furthermore, the
reference should, as far as possible, remain valid for the expected life of the document. The reference shall include the
method of access to the referenced document and the full network address, with the same punctuation and use of upper
case and lower case letters.
NOTE: While any hyperlinks included in this clause were valid at the time of publication ETSI cannot guarantee
their long term validity.
2.1 Normative references
The following referenced documents are indispensable for the application of the present document. For dated
references, only the edition cited applies. For non-specific references, the latest edition of the referenced document
(including any amendments) applies.
[1] ETSI TS 102 144: "Services and Protocols for Advanced Networks (SPAN); MTP/SCCP/SSCOP
and SIGTRAN (Transport of SS7 over IP); Stream Control Transmission Protocol (SCTP)
[Endorsement of RFC 2960 and RFC 3309, modified]".
[2] ITU-T Recommendation Y.2011: "General principles and general reference model for next
generation networks".
[3] ETSI TS 123 002: "Digital cellular telecommunications system (Phase 2+); Universal Mobile
Telecommunications System (UMTS); Network architecture (3GPP TS 23.002 version 7.3.1)".
[4] ETSI TS 123 228: "Digital cellular telecommunications system (Phase 2+); Universal Mobile
Telecommunications System (UMTS); IP Multimedia Subsystem (IMS); Stage 2
(3GPP TS 23.228)".
[5] ETSI ES 282 004: "Telecommunications and Internet converged Services and Protocols for
Advanced Networking (TISPAN); NGN Functional Architecture; Network Attachment
Sub-System (NASS)".
[6] ETSI ES 282 003: "Telecommunications and Internet converged Services and Protocols for
Advanced Networking (TISPAN); Functional Architecture; Resource and Admission Control
Sub-system (RACS)".
ETSI

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7 Final draft ETSI ES 282 001 V2.0.0 (2007-11)
[7] ETSI ES 282 007: "Telecommunications and Internet converged Services and Protocols for
Advanced Networking (TISPAN); Core IMS architecture".
[8] ETSI ES 282 002: "Telecommunications and Internet converged Services and Protocols for
Advanced Networking (TISPAN); Functional architecture for PSTN/ISDN Emulation".
[9] ETSI TS 182 012: "Telecommunications and Internet converged Services and Protocols for
Advanced Networking (TISPAN); IMS-based PSTN/ISDN Emulation subsystem: Functional
architecture".
[10] ETSI TS 182 027: "Telecommunications and Internet converged Services and Protocols for
Advanced Networking (TISPAN); IPTV Architecture; IPTV functions supported by the IMS
subsystem".
[11] ETSI TS 182 028: "Telecommunications and Internet converged Services and Protocols for
Advanced Networking (TISPAN); IPTV Architecture; Dedicated subsystem for IPTV functions".
[12] ETSI TS 185 003: "Telecommunications and Internet converged Services and Protocols for
Advanced Networking (TISPAN); Customer Network Gateway architecture and interfaces ".
[13] ETSI TS 185 006: "Telecommunications and Internet converged Services and Protocols for
Advanced Networking (TISPAN); TISPAN Customer Devices architecture and interfaces".
[14] ETSI TS 181 006: "Telecommunications and Internet converged Services and Protocols for
Advanced Networking (TISPAN); Direct Communication Service in NGN; Service Description
[Endorsement of OMA-ERELD-PoC-V1]".
[15] ITU-T Recommendation G.8010: "MPLS layer network architecture".
3 Definitions and abbreviations
3.1 Definitions
For the purposes of the present document, the following terms and definitions apply:
access network: collection of network entities and interfaces that provide the underlying IP transport connectivity
between end user devices and NGN entities
core network: portion of the delivery system composed of networks, systems equipment and infrastructures,
connecting the service providers to the access network
functional entity: entity that comprises a specific set of functions at a given location
NOTE: Functional entities are logical concepts, grouping of functional entities are used to describe practical
physical realizations.
user equipment: one or more devices allowing a user to access services delivered by TISPAN NGN networks
NOTE: This includes devices when under user control commonly referred to as IAD, ATA, RGW, TE, etc., UE
does not include network controlled entities such as network terminations and access gateways.
3.2 Abbreviations
For the purposes of the present document, the following abbreviations apply:
3GPP Third Generation Project Partnership
A-MGF Access Media Gateway Function
AN Access Node
ARF Access Relay Function
AS Application Server
ASF Application Server Function
ETSI

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8 Final draft ETSI ES 282 001 V2.0.0 (2007-11)
ATA Analogue Terminal Adaptor
AUC AUthentication Centre
BGF Border Gateway Function
BGW Border GateWay
BNG Broadband Network Gateway
BRAS Broadband Remote Access Server
BTF Basic Transport Function
C-BGF Core Border Gateway Function
CND Customer Network Device
CNG Customer Network Gateway
CPN Customer Premises Network
CSCF Call Session Control Function
DHCP Dynamic Host Configuration Protocol
DSLAM Digital Subscriber Line Access Multiplexer
ENUM tElephone NUmber Mapping
ECF Elementary Control Function
EFF Elementary Forwarding Function
HLR Home Location Register
HSS Home Subscriber Server
IAD Integrated Access Device
IBCF Interconnection Border Control Function
I-BGF Interconnection-Border Gateway Function
I-CSCF Interrogating-Call Session Control Function
IGMP Internet Group Management Protocol
IMS IP Multimedia Subsystem
IMS-MGW IMS-Media Gateway
IP Internet Protocol
ISDN Integrated Services Digital Network
IVR Interactive Voice Response
IWF InterWorking Function
MGCF Media Gateway Control Function
MGF Media Gateway Function
MLD Multicast Listener Discovery
MRFP Multimedia Resource Function Processor
MTP Message Transfer Part
NAPT Network Address and Port Translation
NAPT-PT NAPT and Protocol Translation
NASS Network Attachment SubSystem
NGN Next Generation Network
OSA Open Service Access
PES PSTN/ISDN Emulation Subsystem
PIM Protocol Independent Multicast
PPP Point-to-Point Protocol
PSTN Public Switched Telephony Network
RACS Resource and Admission Control Subsystem
RADIUS Remote Access Dial In User Service
RCEF Resource Control Enforcement Function
RGW Residential GateWay
R-MGF Residential Media Gateway Function
SCCP Signalling Connection Control Part
SCTP Stream Control Transmission Protocol
SGCF Signalling Gateway Control Function
SGF Signalling Gateway Function
SGW Signalling GateWay
SLF Subscription Locator Function
TDM Time Division Multiplexing
TE Terminal Equipment
TGCF Trunking GateWay Function
TGW Trunking GateWay
T-MGF Trunking-Media Gateway Function
UE User Equipment
UPSF User Profile Server Function
ETSI

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Other networks
User Equipment
 9 Final draft ETSI ES 282 001 V2.0.0 (2007-11)
4 Overall architecture
The NGN functional architecture described in the present document complies with the ITU-T general reference model
for next generation networks [2] and is structured according to a service layer and an IP-based transport layer.
The service layer comprises the following components:
• the core IP Multimedia Subsystem (IMS);
• the PSTN/ISDN Emulation Subsystem (PES);
• other multimedia subsystems (e.g. IPTV Dedicated Subsystem) and applications;
• common components (i.e. used by several subsystems) such as those required for accessing applications,
charging functions, user profile management, security management, routing data bases (e.g. ENUM), etc.
This subsystem-oriented architecture enables the addition of new subsystems over the time to cover new demands and
service classes. It also provides the ability to import (and adapt) subsystems defined by other standardization bodies.
IP-connectivity is provided to NGN user equipment by the transport layer, under the control of the network attachment
subsystem (NASS) and the resource and admission control subsystem (RACS). These subsystems hide the transport
technology used in access and core networks below the IP layer.
The architecture described in the present document and related subsystems specifications is a functional architecture.
Each subsystem is specified as a set of functional entities and related interfaces. As a result implementers may choose to
combine functional entities where this makes sense in the context of the business models, services and capabilities
being supported. Where functional entities are combined the interface between them is internal, is hidden and
un-testable.
Figure 1 provides an overview of the NGN architecture. An example of realization of this functional architecture, with
an xDSL-based access network is provided in annex A.
Applications
Service Layer
Other
Subsyst ems
User
profiles
Core IMS
PSTN/ISDN
Emulat ion
Subsyst em
Transport Layer
Network
Attachment
Resource and
Subsyst em
Admission Control
Subsyst em
Transport processing functions

Figure 1: TISPAN NGN overall architecture
The functional entities that make up a subsystem may be distributed over network/service provider domains (see
figure 2). The network attachment subsystem may be distributed between a visited and a home network. Service-layer
subsystems that support nomadism may also be distributed between a visited and a home network.
ETSI

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10 Final draft ETSI ES 282 001 V2.0.0 (2007-11)
Visited Network Home Network
Distributed Subsystem
Core Network Core Network
(control) (control)
UE
Access Core Core
Network Networks Networks
(transfer) (transfer) (transfer)

Figure 2: Distributed subsystems
This architecture supports the service capabilities and requirements identified in TS 181 006 [14].
An access network comprises an access segment and an aggregation segment (figure 2a). The access segment (also
known as "last mile segment" stretches from the customer premises to the first network node (also known as the "access
node"). The aggregation segment comprises the transport network elements enabling one or more access nodes to be
connected to a core network through an IP Edge Router, at the Di reference point.
NOTE: In configurations where the access segment uses the DSL technology, the aggregation segment generally
uses ATM or Giga Ethernet. The IP Edge is known as a Broadband Remote Access Server (BRAS) or
Broadband Network Gateway (BNG).
Access
IP-Edge
Transport Network Elements
Node
Di
Access Segment Aggregation Segment

Figure 2a: Access and aggregation segments
5 Transport layer
The transport layer comprises a transport control sublayer on top of transport processing functions in the access and
core networks. Equivalent functionality in the User Equipment is defined in clause 8.
The transport control sublayer is further divided in two subsystems:
• the Network Attachment Subsystem (NASS);
• the Resource and Admission Control Subsystem (RACS).
5.1 Transport control sublayer
5.1.1 Network Attachment Subsystem (NASS)
The Network Attachment Subsystem provides the following functionalities:
• dynamic provision of IP addresses and other terminal configuration parameters;
• authentication taking place at the IP layer, prior or during the address allocation procedure;
ETSI
User
Equipment
Core Network

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User Equipment
 11 Final draft ETSI ES 282 001 V2.0.0 (2007-11)
• authorization of network access based on user profiles;
• access network configuration based on user profiles;
• location management taking place at the IP layer.
The NGN architecture does not mandate a single NASS instance to support multiple access networks. This does not
prevent operators from deploying NASS functions that are common to multiple access networks (e.g. one user profile
database common to different access networks).
NOTE: The user profiles mentioned above are related to the access subscription only.
The NASS interfaces with the following entities (see figure 2b):
• the user equipment at the e3 reference point for configuration purposes;
• transport processing entities acting as relays to/from the user equipment for address allocation, authentication
and authorization purposes (a1 and a3 reference points);
• the Resource and Admission Control Subsystem at the e4 reference point for exporting subscriber access
profile information;
• service-control subsystems and applications in the service layer at the e2 reference point for exporting
information on access sessions and supporting notification services.
Applications
Service Layer
….
User
profiles
…
Service
Cont rol
Subsyst ems
e2
Transport Layer
Network
e3
e4
Attachment
Resource and
Subsyst em
Admission Control
Subsyst em
a1,a3
Transport processing functions

Figure 2b: NASS external reference points
Further details about the functionalities and architecture of the NASS can be found in ES 282 004 [5].
5.1.2 Resource and Admission Control Subsystem (RACS)
RACS is the TISPAN NGN subsystem responsible for the implementation of procedures and mechanisms handling
policy-based resource reservation and admission control for both unicast and multicast traffic in access networks and
core networks.
Besides acting as a resource control framework, RACS also includes support for controlling Network Address
Translation (NAT) at the edge of networks and assisting in remote NAT traversal. Furthermore, RACS also covers
aspects related to the setting and modification of traffic policies, end to end quality of service and transport-level
charging.
ETSI

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User Equipment
 12 Final draft ETSI ES 282 001 V2.0.0 (2007-11)
The RACS interfaces with transport processing functions at the Re and Ia reference points and with the following
subsystems (see figure 2c):
• The Network Attachment Subsystem at the e4 reference point for obtaining subscriber access profil
information.
• Service-control subsystems and applications in the service layer at the Gq' reference point for exposing the
services it provides.
Applications
Service Layer
….
User
profiles
…
Service
Cont rol
Subsyst ems
Gq'
Transport Layer
Gq'
Network
e4
Attachment
Resource and
Subsyst em
Admission Control
Subsyst em
Re Ia
Transport processing functions
Transport Processing Functions

Figure 2c: RACS external reference points
Further details about the functionalities and architecture of the RACS are defined in ES 282 003 [6].
5.2 Transport processing functions
Transport processing functions in the access and core networks include basic elementary functions supporting packet
forwarding and routing, and more specific group of functions defined as functional entities.
These are:
• Media Gateway Function (MGF).
• Border Gateway Function (BGF).
• Resource Control Enforcement Function (RCEF)
...

SLOVENSKI STANDARD
SIST ES 282 001 V2.0.0:2008
01-julij-2008
Zlite telekomunikacijske in internetne storitve ter protokoli za napredno omreženje
(TISPAN) - Funkcijska arhitektura omrežja NGN
Telecommunications and Internet converged Services and Protocols for Advanced
Networking (TISPAN) - NGN Functional Architecture
Ta slovenski standard je istoveten z: ES 282 001 Version 2.0.0
ICS:
33.040.01 Telekomunikacijski sistemi Telecommunication systems
na splošno in general
33.080 Digitalno omrežje z Integrated Services Digital
integriranimi storitvami Network (ISDN)
(ISDN)
SIST ES 282 001 V2.0.0:2008 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST ES 282 001 V2.0.0:2008

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SIST ES 282 001 V2.0.0:2008

ETSI ES 282 001 V2.0.0 (2008-03)
ETSI Standard


Telecommunications and Internet converged Services and
Protocols for Advanced Networking (TISPAN);
NGN Functional Architecture

---------------------- Page: 3 ----------------------

SIST ES 282 001 V2.0.0:2008
 2 ETSI ES 282 001 V2.0.0 (2008-03)



Reference
RES/TISPAN-02046-NGN-R2
Keywords
architecture, functional
ETSI
650 Route des Lucioles
F-06921 Sophia Antipolis Cedex - FRANCE

Tel.: +33 4 92 94 42 00  Fax: +33 4 93 65 47 16

Siret N° 348 623 562 00017 - NAF 742 C
Association à but non lucratif enregistrée à la
Sous-Préfecture de Grasse (06) N° 7803/88

Important notice
Individual copies of the present document can be downloaded from:
http://www.etsi.org
The present document may be made available in more than one electronic version or in print. In any case of existing or
perceived difference in contents between such versions, the reference version is the Portable Document Format (PDF).
In case of dispute, the reference shall be the printing on ETSI printers of the PDF version kept on a specific network drive
within ETSI Secretariat.
Users of the present document should be aware that the document may be subject to revision or change of status.
Information on the current status of this and other ETSI documents is available at
http://portal.etsi.org/tb/status/status.asp
If you find errors in the present document, please send your comment to one of the following services:
http://portal.etsi.org/chaircor/ETSI_support.asp
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 2008.
All rights reserved.

TM TM TM TM
DECT , PLUGTESTS , UMTS , TIPHON , the TIPHON logo and the ETSI logo are Trade Marks of ETSI registered
for the benefit of its Members.
TM
3GPP is a Trade Mark of ETSI registered for the benefit of its Members and of the 3GPP Organizational Partners.
ETSI

---------------------- Page: 4 ----------------------

SIST ES 282 001 V2.0.0:2008
 3 ETSI ES 282 001 V2.0.0 (2008-03)
Contents
Intellectual Property Rights.5
Foreword.5
1 Scope.6
2 References.6
2.1 Normative references.6
3 Definitions and abbreviations.7
3.1 Definitions.7
3.2 Abbreviations.7
4 Overall architecture .9
5 Transport layer.10
5.1 Transport control sublayer.11
5.1.1 Network Attachment Subsystem (NASS).11
5.1.2 Resource and Admission Control Subsystem (RACS) .12
5.2 Transport processing functions.12
5.2.1 Border Gateway Function (BGF).13
5.2.1A Resource Control Enforcement Function (RCEF) .14
5.2.2 Void.14
5.2.3 Access Relay Function (ARF) .14
5.2.4 Media Gateway Function (MGF).15
5.2.5 Media Resource Function Processor (MRFP) .15
5.2.6 Signalling Gateway Function (SGF).15
5.2.7 Access Management Function (AMF).15
5.2.8 Basic Transport Function (BTF).15
5.2.8.1 Elementary Forwarding Function (EFF) .16
5.2.8.2 Elementary Control Function (ECF) .16
6 Service Layer Model .16
6.1 The "Core" IP Multimedia Subsystem (IMS).16
6.2 The PSTN/ISDN Emulation subsystem (PES).17
6.3 The IPTV Subsystem.17
6.4 Void.17
6.5 Common components.17
6.5.1 User Profile Server Function (UPSF) .18
6.5.2 Subscription Locator Function (SLF) .18
6.5.3 Application Server Function (ASF) .18
6.5.4 Void.18
6.5.5 Interworking Function (IWF) .18
6A Charging and Data Collection Functions .19
7 NGN Interconnection .19
7.1 General.19
7.2 Interconnection reference points and functions.19
7.2.1 Interconnection at the transport layer .19
7.2.1.1 Transport processing sublayer.19
7.2.1.2 NASS.20
7.2.1.3 RACS .20
7.2.2 Interconnection at the Service Layer .21
7.3 NGN Interconnection types.22
7.3.1 SoIx in the NGN Architecture .22
7.3.2 CoIx in the NGN Architecture.23
7.3.3 PSTN Interconnection types.24
7.3.4 NGN Direct and Indirect interconnection modes.25
8 User Equipment (UE).28
ETSI

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SIST ES 282 001 V2.0.0:2008
 4 ETSI ES 282 001 V2.0.0 (2008-03)
8.1 Overview .28
8.2 Authentication.28
8.3 Reference points.29
8.3.1 Reference points to the core IMS.29
8.3.2 Reference points to the PSTN/ISDN Emulation subsystem .29
8.3.3 Reference points with applications .30
8.3.4 Reference points with the NASS .30
8.3.5 Reference points with the RACS .30
8.3.6 Reference points with transport processing functions.30
8.3.7 Reference points with access media gateway functions.30
Annex A (informative): Example of physical configuration for xDSL access.31
Annex B (informative): Transport architecture for multicast .32
B.1 Introduction.32
B.2 Multicast Functions in Transport Plane.32
History .34

ETSI

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SIST ES 282 001 V2.0.0:2008
 5 ETSI ES 282 001 V2.0.0 (2008-03)
Intellectual Property Rights
IPRs essential or potentially essential to the present document may have been declared to ETSI. The information
pertaining to these essential IPRs, if any, is publicly available for ETSI members and non-members, and can be found
in ETSI SR 000 314: "Intellectual Property Rights (IPRs); Essential, or potentially Essential, IPRs notified to ETSI in
respect of ETSI standards", which is available from the ETSI Secretariat. Latest updates are available on the ETSI Web
server (http://webapp.etsi.org/IPR/home.asp).
Pursuant to the ETSI IPR Policy, no investigation, including IPR searches, has been carried out by ETSI. No guarantee
can be given as to the existence of other IPRs not referenced in ETSI SR 000 314 (or the updates on the ETSI Web
server) which are, or may be, or may become, essential to the present document.
Foreword
This ETSI Standard (ES) has been produced by ETSI Technical Committee Telecommunications and Internet
converged Services and Protocols for Advanced Networking (TISPAN).
ETSI

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SIST ES 282 001 V2.0.0:2008
 6 ETSI ES 282 001 V2.0.0 (2008-03)
1 Scope
The present document describes the overall TISPAN NGN functional architecture, its subsystems and the relationships
between them.
2 References
References are either specific (identified by date of publication and/or edition number or version number) or
non-specific.
• For a specific reference, subsequent revisions do not apply.
• Non-specific reference may be made only to a complete document or a part thereof and only in the following
cases:
- if it is accepted that it will be possible to use all future changes of the referenced document for the
purposes of the referring document;
- for informative references.
Referenced documents which are not found to be publicly available in the expected location might be found at
http://docbox.etsi.org/Reference.
For online referenced documents, information sufficient to identify and locate the source shall be provided. Preferably,
the primary source of the referenced document should be cited, in order to ensure traceability. Furthermore, the
reference should, as far as possible, remain valid for the expected life of the document. The reference shall include the
method of access to the referenced document and the full network address, with the same punctuation and use of upper
case and lower case letters.
NOTE: While any hyperlinks included in this clause were valid at the time of publication ETSI cannot guarantee
their long term validity.
2.1 Normative references
The following referenced documents are indispensable for the application of the present document. For dated
references, only the edition cited applies. For non-specific references, the latest edition of the referenced document
(including any amendments) applies.
[1] ETSI TS 102 144: "Services and Protocols for Advanced Networks (SPAN); MTP/SCCP/SSCOP
and SIGTRAN (Transport of SS7 over IP); Stream Control Transmission Protocol (SCTP)
[Endorsement of RFC 2960 and RFC 3309, modified]".
[2] ITU-T Recommendation Y.2011: "General principles and general reference model for next
generation networks".
[3] ETSI TS 123 002: "Digital cellular telecommunications system (Phase 2+); Universal Mobile
Telecommunications System (UMTS); Network architecture (3GPP TS 23.002 version 7.3.1)".
[4] ETSI TS 123 228: "Digital cellular telecommunications system (Phase 2+); Universal Mobile
Telecommunications System (UMTS); IP Multimedia Subsystem (IMS); Stage 2
(3GPP TS 23.228)".
[5] ETSI ES 282 004: "Telecommunications and Internet converged Services and Protocols for
Advanced Networking (TISPAN); NGN Functional Architecture; Network Attachment
Sub-System (NASS)".
[6] ETSI ES 282 003: "Telecommunications and Internet converged Services and Protocols for
Advanced Networking (TISPAN); Resource and Admission Control Sub-system (RACS);
Functional Architecture".
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 7 ETSI ES 282 001 V2.0.0 (2008-03)
[7] ETSI ES 282 007: "Telecommunications and Internet converged Services and Protocols for
Advanced Networking (TISPAN); IP Multimedia Subsystem (IMS); Functional architecture".
[8] ETSI ES 282 002: "Telecommunications and Internet converged Services and Protocols for
Advanced Networking (TISPAN); PSTN/ISDN Emulation Sub-system (PES); Functional
architecture".
[9] ETSI TS 182 012: "Telecommunications and Internet converged Services and Protocols for
Advanced Networking (TISPAN); IMS-based PSTN/ISDN Emulation Subsystem; Functional
architecture".
[10] ETSI TS 182 027: "Telecommunications and Internet converged Services and Protocols for
Advanced Networking (TISPAN); IPTV Architecture; IPTV functions supported by the IMS
subsystem".
[11] ETSI TS 182 028: "Telecommunications and Internet converged Services and Protocols for
Advanced Networking (TISPAN); IPTV Architecture; Dedicated subsystem for IPTV functions".
[12] ETSI TS 185 003: "Telecommunications and Internet converged Services and Protocols for
Advanced Networking (TISPAN); TISPAN CNG Architecture and Interfaces and Reference
Points;".
[13] ETSI TS 185 006: "Telecommunications and Internet converged Services and Protocols for
Advanced Networking (TISPAN); TISPAN Customer Devices architecture and interfaces".
[14] ETSI TS 181 006: "Telecommunications and Internet converged Services and Protocols for
Advanced Networking (TISPAN); Direct Communication Service in NGN; Service Description
[Endorsement of OMA-ERELD-PoC-V1]".
[15] ITU-T Recommendation G.8010: "Architecture of Ethernet layer networks".
3 Definitions and abbreviations
3.1 Definitions
For the purposes of the present document, the following terms and definitions apply:
access network: collection of network entities and interfaces that provide the underlying IP transport connectivity
between end user devices and NGN entities
core network: portion of the delivery system composed of networks, systems equipment and infrastructures,
connecting the service providers to the access network
functional entity: entity that comprises a specific set of functions at a given location
NOTE: Functional entities are logical concepts, grouping of functional entities are used to describe practical
physical realizations.
user equipment: one or more devices allowing a user to access services delivered by TISPAN NGN networks
NOTE: This includes devices when under user control commonly referred to as IAD, ATA, RGW, TE, etc., UE
does not include network controlled entities such as network terminations and access gateways.
3.2 Abbreviations
For the purposes of the present document, the following abbreviations apply:
3GPP Third Generation Project Partnership
A-MGF Access Media Gateway Function
AN Access Node
ARF Access Relay Function
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AS Application Server
ASF Application Server Function
ATA Analogue Terminal Adaptor
AUC AUthentication Centre
BGF Border Gateway Function
BGW Border GateWay
BNG Broadband Network Gateway
BRAS Broadband Remote Access Server
BTF Basic Transport Function
C-BGF Core Border Gateway Function
CND Customer Network Device
CNG Customer Network Gateway
CPN Customer Premises Network
CSCF Call Session Control Function
DHCP Dynamic Host Configuration Protocol
DSLAM Digital Subscriber Line Access Multiplexer
ENUM tElephone NUmber Mapping
ECF Elementary Control Function
EFF Elementary Forwarding Function
HLR Home Location Register
HSS Home Subscriber Server
IAD Integrated Access Device
IBCF Interconnection Border Control Function
I-BGF Interconnection-Border Gateway Function
I-CSCF Interrogating-Call Session Control Function
IGMP Internet Group Management Protocol
IMS IP Multimedia Subsystem
IMS-MGW IMS-Media Gateway
IP Internet Protocol
ISDN Integrated Services Digital Network
IVR Interactive Voice Response
IWF InterWorking Function
MGCF Media Gateway Control Function
MGF Media Gateway Function
MLD Multicast Listener Discovery
MRFP Multimedia Resource Function Processor
MTP Message Transfer Part
NAPT Network Address and Port Translation
NAPT-PT NAPT and Protocol Translation
NASS Network Attachment SubSystem
NGN Next Generation Network
OSA Open Service Access
PES PSTN/ISDN Emulation Subsystem
PIM Protocol Independent Multicast
PPP Point-to-Point Protocol
PSTN Public Switched Telephony Network
RACS Resource and Admission Control Subsystem
RADIUS Remote Access Dial In User Service
RCEF Resource Control Enforcement Function
RGW Residential GateWay
R-MGF Residential Media Gateway Function
SCCP Signalling Connection Control Part
SCTP Stream Control Transmission Protocol
SGCF Signalling Gateway Control Function
SGF Signalling Gateway Function
SGW Signalling GateWay
SLF Subscription Locator Function
TDM Time Division Multiplexing
TE Terminal Equipment
TGCF Trunking GateWay Function
TGW Trunking GateWay
T-MGF Trunking-Media Gateway Function
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Other networks
User Equipment
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 9 ETSI ES 282 001 V2.0.0 (2008-03)
UE User Equipment
UPSF User Profile Server Function
4 Overall architecture
The NGN functional architecture described in the present document complies with the ITU-T general reference model
for next generation networks [2] and is structured according to a service layer and an IP-based transport layer.
The service layer comprises the following components:
• the core IP Multimedia Subsystem (IMS);
• the PSTN/ISDN Emulation Subsystem (PES);
• other multimedia subsystems (e.g. IPTV Dedicated Subsystem) and applications;
• common components (i.e. used by several subsystems) such as those required for accessing applications,
charging functions, user profile management, security management, routing data bases (e.g. ENUM), etc.
This subsystem-oriented architecture enables the addition of new subsystems over the time to cover new demands and
service classes. It also provides the ability to import (and adapt) subsystems defined by other standardization bodies.
IP-connectivity is provided to NGN user equipment by the transport layer, under the control of the network attachment
subsystem (NASS) and the resource and admission control subsystem (RACS). These subsystems hide the transport
technology used in access and core networks below the IP layer.
The architecture described in the present document and related subsystems specifications is a functional architecture.
Each subsystem is specified as a set of functional entities and related interfaces. As a result implementers may choose to
combine functional entities where this makes sense in the context of the business models, services and capabilities
being supported. Where functional entities are combined the interface between them is internal, is hidden and
un-testable.
Figure 1 provides an overview of the NGN architecture. An example of realization of this functional architecture, with
an xDSL-based access network is provided in annex A.
Applications
Service Layer
Other
Subsyst ems
User
profiles
Core IMS
PSTN/ISDN
Emulat ion
Subsyst em
Transport Layer
Network
Attachment
Resource and
Subsyst em
Admission Control
Subsyst em
Transport processing functions

Figure 1: TISPAN NGN overall architecture
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The functional entities that make up a subsystem may be distributed over network/service provider domains (see
figure 2). The network attachment subsystem may be distributed between a visited and a home network. Service-layer
subsystems that support nomadism may also be distributed between a visited and a home network.
Visited Network Home Network
Distributed Subsystem
Core Network Core Network
(control) (control)
UE
Access Core Core
Network Networks Networks
(transfer) (transfer) (transfer)

Figure 2: Distributed subsystems
This architecture supports the service capabilities and requirements identified in TS 181 006 [14].
An access network comprises an access segment and an aggregation segment (figure 2a). The access segment (also
known as "last mile segment" stretches from the customer premises to the first network node (also known as the "access
node"). The aggregation segment comprises the transport network elements enabling one or more access nodes to be
connected to a core network through an IP Edge Router, at the Di reference point.
NOTE: In configurations where the access segment uses the DSL technology, the aggregation segment generally
uses ATM or Giga Ethernet. The IP Edge is known as a Broadband Remote Access Server (BRAS) or
Broadband Network Gateway (BNG).
Access
IP-Edge
Transport Network Elements
Node
Di
Access Segment Aggregation Segment

Figure 2a: Access and aggregation segments
5 Transport layer
The transport layer comprises a transport control sublayer on top of transport processing functions in the access and
core networks. Equivalent functionality in the User Equipment is defined in clause 8.
The transport control sublayer is further divided in two subsystems:
• the Network Attachment Subsystem (NASS);
• the Resource and Admission Control Subsystem (RACS).
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5.1 Transport control sublayer
5.1.1 Network Attachment Subsystem (NASS)
The Network Attachment Subsystem provides the following functionalities:
• dynamic provision of IP addresses and other terminal configuration parameters;
• authentication taking place at the IP layer, prior or during the address allocation procedure;
• authorization of network access based on user profiles;
• access network configuration based on user profiles;
• location management taking place at the IP layer.
The NGN architecture does not mandate a single NASS instance to support multiple access networks. This does not
prevent operators from deploying NASS functions that are common to multiple access networks (e.g. one user profile
database common to different access networks).
NOTE: The user profiles mentioned above are related to the access subscription only.
The NASS interfaces with the following entities (see figure 2b):
• the user equipment at the e3 reference point for configuration purposes;
• transport processing entities acting as relays to/from the user equipment for address allocation, authentication
and authorization purposes (a1 and a3 reference points);
• the Resource and Admission Control Subsystem at the e4 reference point for exporting subscriber access
profile information;
• service-control subsystems and applications in the service layer at the e2 reference point for exporting
information on access sessions and supporting notification services.
Applications
Service Layer
….
User
profiles
…
Service
Cont rol
Subsyst ems
e2
Transport Layer
e3 Network
e4
Attachment
Resource and
Subsyst em
Admission Control
Subsyst em
a1,a3
Transport processing functions

Figure 2b: NASS external reference points
Further details about the functionalities and architecture of the NASS can be found in ES 282 004 [5].
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5.1.2 Resource and Admission Control Subsystem (RACS)
RACS is the TISPAN NGN subsystem responsible for the implementation of procedures and mechanisms handling
policy-based resource reservation and admission control for both unicast and multicast traffic in access networks and
core networks.
Besides acting as a resource control framework, RACS also includes support for controlling Network Address
Translation (NAT) at the edge of networks and assisting in remote NAT traversal. Furthermore, RACS also covers
aspects related to the setting and modification of traffic policies, end to end quality of service and transport-level
charging.
The RACS interfaces with transport processing functions at the Re and Ia reference points and with the following
subsystems (see figure 2c):
•
...