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1 © NOKIA NGN - HUT.PPT /13-04-2005 / Miguel. An. Garcia Next Generation Networks (NGN) Lecture at the Signalling Protocols Course Helsinki University of Technology [email protected] 13 April 2005, Espoo, Finland Nokia Research Center 2 © NOKIA NGN - HUT.PPT /13-04-2005 / Miguel. An. Garcia Outline Concept Standard bodies NGN overall architecture Architecture of each of the NGN subsystems

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Page 1: Next Generation Networks (NGN) - … Generation Networks (NGN) Lecture at the Signalling Protocols Course Helsinki University of Technology ... • Next Generation Networks are largely

1 © NOKIA NGN - HUT.PPT /13-04-2005 / Miguel. An. Garcia

Next Generation Networks (NGN)

Lecture at the Signalling Protocols CourseHelsinki University of Technology

[email protected] April 2005, Espoo, Finland

Nokia Research Center

2 © NOKIA NGN - HUT.PPT /13-04-2005 / Miguel. An. Garcia

Outline• Concept• Standard bodies• NGN overall architecture• Architecture of each of the NGN subsystems

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3 © NOKIA NGN - HUT.PPT /13-04-2005 / Miguel. An. Garcia

The concept

A NGN is a packet-based network able to provide Telecommunication services and able to make use of multiple broadband,

QoS-enabled transport technologies and in which service-related functions are independent from underlying transport-related technologies.

It enables unfettered access for users to networks and to competing service providers and/or services of their choice.

It supports generalized mobility which will allow consistent and ubiquitous provision of services to users.

Source: ITU-T Rec. Y.2001

4 © NOKIA NGN - HUT.PPT /13-04-2005 / Miguel. An. Garcia

NGN characteristics•A new telecommunications network for broadband fixed access•NGN facilitates convergence of networks and services•NGN enables different business models across access, core network and service domains•NGN will be an IP based network•SIP will be used for call & session control•3GPP release 6 IMS will be the base for NGN IP Multimedia Subsystem•NGN enables any IP access to Operator IMS; from

•Mobile domain•Home domain•Enterprise domain

•NGN enables service mobility•NGN enables interworking towards circuit switched voice •NGN maintains Service Operator control for IMS signaling & media traffic

•A new telecommunications network for broadband fixed access•NGN facilitates convergence of networks and services•NGN enables different business models across access, core network and service domains•NGN will be an IP based network•SIP will be used for call & session control•3GPP release 6 IMS will be the base for NGN IP Multimedia Subsystem•NGN enables any IP access to Operator IMS; from

•Mobile domain•Home domain•Enterprise domain

•NGN enables service mobility•NGN enables interworking towards circuit switched voice •NGN maintains Service Operator control for IMS signaling & media traffic

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5 © NOKIA NGN - HUT.PPT /13-04-2005 / Miguel. An. Garcia

The players

3GPP

ITU-T NGN FG

ATISNGN FG ETSI TISPAN

LegendATIS NGN FG: Alliance for Telecommunication Industry Solutions, Next Generation Networks Focus Group

ITU-T NGN FG: International Telecommunication Union (Telecom), Next Generation Networks Focus Group

ETSI TISPAN:European Telecommunications Standards Institute, Telecoms & Internet converged Services & Protocols for Advanced Networks

3GPP: Third Generation Partnership Project

6 © NOKIA NGN - HUT.PPT /13-04-2005 / Miguel. An. Garcia

ITU-T NGN-FG• ITU-T created the NGN Focus Group (NGN-FG) in June 2004.

• Main topics:• Functional & Nomadicity Architecture (based on IMS & non-IMS)• QoS (include the xDSL Access)• Security Capability (inc. Authentication)• NGN Control and Signaling Capability• Evolution from the existing networks to NGN

• Service types:• PSTN/ISDN Emulation services• PSTN/ISDN Simulation services• Multimedia services • Internet access • Other services (data services etc.)• Public service aspects (LI, ETS/TDR, etc.)

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7 © NOKIA NGN - HUT.PPT /13-04-2005 / Miguel. An. Garcia

ATIS NGN FG• ATIS is a North American based body that is committed to rapidly

developing and promoting technical and operations standards for the communications and related information technologies industry worldwide using a pragmatic, flexible and open approach.

• ATIS NGN FG is committed to:• Develop a North American set of requirements for NGN that includes multi-

service architectures and an evolution path from currently deployed architectures.

• Review and analyze other international activities underway to define NGN functional and structural architectures, and compare those architectures to the desired ATIS-requirements for NGN.

• Coordinate with other standards bodies to arrive, to the extent possible, at a consistent global view of the NGN.

• Guide the development of NGN standards from a business perspective. • The NGN-FG does not develop standards.• Technical & operational standards will be developed by appropriate

standards developers to include ATIS’ internal committees and other external developers; e.g., ITU-T, ETSI/TISPAN, 3GPP, etc..

8 © NOKIA NGN - HUT.PPT /13-04-2005 / Miguel. An. Garcia

ETSI TISPAN• The European Telecommunications Standards Institute (ETSI) is an

independent, non-profit organization, whose mission is to produce telecommunications standards for today and for the future.

• The Next Generation Network will provide:• A multi-service, multi-protocol, multi-access, IP based network - secure,

reliable and trusted• Multi-services: delivered by a common QoS enabled core network. • Multi-access: several access networks; fixed and mobile terminals.• Not one network, but different networks that interoperate

seamlessly• An enabler for Service Providers to offer

• real-time and non real-time communication services• between peers or in a client-server configuration.

• Nomadicity and Mobility• of both users and devices• intra- and inter-Network Domains, eventually between Fixed and

Mobile networks

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9 © NOKIA NGN - HUT.PPT /13-04-2005 / Miguel. An. Garcia

3GPP• The 3rd Generation Partnership Project (3GPP) is a collaboration

agreement that was established in December 1998. The collaboration agreement brings together a number of telecommunications standards bodies which are known as “Organizational Partners”. The current Organizational Partners are ARIB, CCSA, ETSI, ATIS, TTA, and TTC.

• The original scope of 3GPP was to produce globally applicable Technical Specifications and Technical Reports for a 3rd Generation Mobile System based on evolved GSM core networks and the radio access technologies that they support (i.e., Universal Terrestrial Radio Access (UTRA) both Frequency Division Duplex (FDD) and Time Division Duplex (TDD) modes).

• 3GPP created the IP Multimedia Subsystem (IMS), which is part of 3GPP Release 5 and subsequent releases.

• Next Generation Networks are largely based in IMS• Next Generation Networks are sometimes seen as IMS over fixed

broadband access.• 3GPP remains as the solely “owner” of the IMS specifications.

10 © NOKIA NGN - HUT.PPT /13-04-2005 / Miguel. An. Garcia

ETSI TISPAN overall NGN architecture

Other netw

orks

Other subsystems

Core IMS

PSTN/ISDN Emulationsubsystem

User E

quipment

Service Layer

Transport Layer

Transfer Functions

Resource and Admission Control

Subsystem

Network Attachment Subsystem

Applications

Userprofiles

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11 © NOKIA NGN - HUT.PPT /13-04-2005 / Miguel. An. Garcia

ETSI TISPAN NGN architecture

Resource and Admission Control Subsystem

RACS

Based on3GPP IMS

IP ConnectivityAccess NetworkAnd related functionality

Network AttachmentSubsystem

NASS

Other Multimedia Components …Streaming Services

(RTSP based)

Applications

Core transport Network

3GPP IP-CAN

Access Transport Network

3GPP Terminals

NGN Terminals

CustomerNetworks

UserProfiles

Other N

etworks

LegacyTerminals

GW

PSTN / ISDN Emulation(SIP-I based)

IP Multimedia Component (Core IMS)

(SIP based)Service layer

Transport layer

12 © NOKIA NGN - HUT.PPT /13-04-2005 / Miguel. An. Garcia

NGN architecture principles• A layered approach, including

• A transport layer, including functional entities that do transport routing• A service layer, including functional entities that provide services

• A sub-system oriented approach, enabling: • The addition of new subsystems over the time to cover new demands

and service classes.• To import (and adapt) subsystems from other standardisation bodies.• Flexibility to adjust a subsystem architecture with no or limited impact

on other subsystems.• IP connectivity is provided using two subsystems:

• Network Attachment SubSystem (NASS)• Resource and Admission Control Subsystem (RACS)

• First service-oriented subsystems include • the 3GPP IMS, a PSTN/ISDN Simulation Subsystem• a PSTN/ISDN Emulation Subsystem (PES)

• Future service-oriented subsystems may include• A streaming subsystem• A TV Broadcasting subsystem

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13 © NOKIA NGN - HUT.PPT /13-04-2005 / Miguel. An. Garcia

TISPAN NGN common components

IBCF

IWF

Transfer Functions

Transport control

To/Fromother networks

Control Subsystems

Transport Layer

Service Layer

ASF(type 2)UPSFASF

(type 1) Data Collection

Charging mediation

Mediationto other

management applications

Roughly equivalent to the HSS

(excluding the HLR)

14 © NOKIA NGN - HUT.PPT /13-04-2005 / Miguel. An. Garcia

Common components (1)• Common components are functions that are used by more than a

subsystem• USPF: User Profile Server Function

• Service-level user identification, numbering, and addressing information• Service-level user security information• Service-level user location information• Service-level user profile storage• The IMS part of the USPF is similar to the 3GPP HSS without the

HLR/AUC• SLF: Subscription Locator Function

• Helps locating the USPF of a given user• Like the SLF defined by 3GPP IMS

• ASF: Application Server Function• Offers services• Two types of ASFs:

• Type 1: may interact with RACS for resource control purposes• Type 2: relay on the control subsystem.

– Type 2 is equivalent to the Application Server defined by 3GPP IMS

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15 © NOKIA NGN - HUT.PPT /13-04-2005 / Miguel. An. Garcia

Common Components (2)• Charging Functions

• Data collection functions and mediation functions to the billing systems, • Both on-line and off-line charging.

• IWF: Interworking Function• Between different SIP profiles• Between SIP and H.323

• IBCF: Interconnection Border Control Function• Controls an operator’s boundary• Interacts with RACS• Inserts IWF when appropriate• Screening of signalling based on source/destination addresses

16 © NOKIA NGN - HUT.PPT /13-04-2005 / Miguel. An. Garcia

The Transport layer in NGN

Other netw

orks

Other subsystems

Core IMS

PSTN/ISDN Emulationsubsystem

User E

quipment

Service Layer

Transport Layer

Transfer Functions

Resource and Admission Control

Subsystem

Network Attachment Subsystem

Applications

Userprofiles

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17 © NOKIA NGN - HUT.PPT /13-04-2005 / Miguel. An. Garcia

Transfer Functions

Other netw

orksOther

subsystems

Core IMS

PSTN/ISDN Emulationsubsystem

User E

quipment

Service Layer

Transport Layer

Transfer Functions

Resource and Admission Control

Subsystem

Network Attachment Subsystem

Applications

Userprofiles

18 © NOKIA NGN - HUT.PPT /13-04-2005 / Miguel. An. Garcia

Transfer functions

T-MGF

I-BGFC-BGF

MRFP

Transfer Functions

SGF

ARF

RCEF

Other netw

orks

User E

quipment

Service Layer

A-MGF

NASS RACS

L2TF

Access Network Core Network

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19 © NOKIA NGN - HUT.PPT /13-04-2005 / Miguel. An. Garcia

Transfer functions (2)• BGF: Border Gateway Function

• Interface between two IP transport domains• Open/close gates, packet marking, resource allocation, bandwidth

reservation, NAPT, NAT traversal, incoming traffic policing, usage metering, IPv4/IPv6 interworking, topology hiding

• Three types of BGF:• A-BGF (Access-BGF): located in between access and core network,

at the access network side• C-BGF (Core-BGF): located in between access and core network,

at the core network siee• I-BGF (Interconnection-BGF): located in between two core netwoks

• L2TF: Layer 2 Termination Function• Terminates Layer 2, e.g., PPP or DSLAM

• ARF: Access Relay Function• Relay between the CPE and the NASS• Located in the access network • Resource reservation and admission control

20 © NOKIA NGN - HUT.PPT /13-04-2005 / Miguel. An. Garcia

Transfer functions (3)• MGF: Media Gateway Function

• Media mapping and transcoding between IP and CS networks• Three types of MGF:

• R-MGF Residential MGF: located in the customer premises• A-MGF Access MGF: located in the access or core network• T-MGF Trunking: MGF located in the boundary of the core network

and PSTN/ISDN network• MRFP: Media Resource Function Processor

• Multimedia conferences, media sourcing, IVR capabilities, media content analysis

• SGF: Signalling Gateway Function• Conversion of SS7 protocols to IP control protocols (e.g., SIP)• SS7 screening of MTP and SCCP parameters

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21 © NOKIA NGN - HUT.PPT /13-04-2005 / Miguel. An. Garcia

Resource and Admission Control Subsystem (RACS)

Other netw

orksOther

subsystems

Core IMS

PSTN/ISDN Emulationsubsystem

User E

quipment

Service Layer

Transport Layer

Transfer Functions

Resource and Admission Control

Subsystem

Network Attachment Subsystem

Applications

Userprofiles

22 © NOKIA NGN - HUT.PPT /13-04-2005 / Miguel. An. Garcia

RASS functionality• Support for two types of QoS:

• Guaranteed QoS: resources are reserved• Support for Relative QoS: diffserv marking

• Service Based Local Policy Control: authorisation of QoS requests and definition of the polices to be enforced by the bearer service network elements.

• Resource reservation• Support for two mechanisms

• Application Function (AF)-initiated• CPE-initiated (Authorization token a la 3GPP).

• QoS support over multiple access networks (e.g. ADSL and GPRS) and CPE types.

• Admission Control: Apply admission control to resource reservation requests• Based on knowledge of transport resource availability over the “last-mile access”

and aggregation segments of the access network• NAPT/ Gate Control: controls near-end and far-end NAPT and FW functions, when

required, between:• two core TISPAN NGN networks or, • at the border between core and access TISPAN NGN networks

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23 © NOKIA NGN - HUT.PPT /13-04-2005 / Miguel. An. Garcia

RACS architectureRACS

CPE Access Node

L2TPoint

RCEF

Border Node Ds Di

Transport

A-RACF

NASS

SPDFe4

Rq

Re

AFRACS

CPE Access L2TPoint

RCEF C-BGF

Ds Di

Transport

A-RACF

Ra

NASS

SPDF

Ia

e4

Rq

Re

IP Edge

AF

Gq’

24 © NOKIA NGN - HUT.PPT /13-04-2005 / Miguel. An. Garcia

RACS architecture (2)• SPDF: Service-based Policy Decision Function

• Provides to AF a single point of contact• Authorization decision for QoS resource

• A-RACF: Access Resource and Admission Control Function• Located in the access network • Resource reservation and admission control• In Guaranteed QoS mode, it sets L2/L3 QoS policies in RCEF• In Relative QoS mode, it sets dynamically the diffserv QoS

parameters in RCEF

• C-BGF: Core Border Gateway Function• Essentially, an edge router• Located at the border of networks (access/core – core/core)• NAPT, Gate Control, packet marking, usage metering, policing

enforcement function• SPDF controls the gates of the C-BGF based on a 5-tuple (source and

destination IP addr., source and destination port numbers, protocol)

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25 © NOKIA NGN - HUT.PPT /13-04-2005 / Miguel. An. Garcia

RACS architecture (2)• RCEF: Resource Control Enforcement Function

• Performs policy enforcement under the control of the A-RACF• Located in the access network• Gate control, packet marking, policing• A-RACF controls the gates of the RCEF based on a 5-tuple (source

and destination IP addr., source and destination port numbers, protocol)

• L2TF: Layer 2 Termination Functions• Layer 2 (e.g., PPP, ATM) is terminated here • Authorization decision for QoS resource

• AF: Application Function• Officially, not part of RACS. Just a RACS user• Requests bearers resources, gest informed when resources are

reserved and released• It is specific of the application. E.g., P-CSCF in IMS

26 © NOKIA NGN - HUT.PPT /13-04-2005 / Miguel. An. Garcia

Network Attachment Subsystem (NASS)

Other netw

orks

Other subsystems

Core IMS

PSTN/ISDN Emulationsubsystem

User E

quipment

Service Layer

Transport Layer

Transfer Functions

Resource and Admission Control

Subsystem

Network Attachment Subsystem

Applications

Userprofiles

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27 © NOKIA NGN - HUT.PPT /13-04-2005 / Miguel. An. Garcia

NASS functionality• Dynamic provision of IP address and other user equipment configuration

parameters (e.g., using DHCP)• User authentication, prior or during the IP address allocation procedure • User authentication based on user network profile

• Based on PPP, IEEE 802.11X or IETF PANA• Line authentication based on Layer 2 line identification• Location management (e.g. for emergency call, …)• Customer Premises Equipment configuration• The NASS can be distributed between a visited and a home network

• Allows nomadicity and roaming

• P-CSCF announcement

28 © NOKIA NGN - HUT.PPT /13-04-2005 / Miguel. An. Garcia

NASS architecture

a4

Service control subsystems and

applications

TE CNG

a3 a1

a2

e1

e2 e4

e3

Resource and

Admission Control

Subsystem CLF

NACF CPECF

AMF

PDBF UAAF

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29 © NOKIA NGN - HUT.PPT /13-04-2005 / Miguel. An. Garcia

NASS architecture (2)• Network Address Configuration Function (NACF):

• IP address allocation to the CPE• Distribution of other network configuration parameters such as address

of DNS server(s), address of signalling proxies for specific protocols (e.g., P-CSCF)

• Typically implemented as RADIUS servers or DHCP servers• Access Management Function (AMF):

• Translates network access signalling between CPE and NACF/UAAF • Forwards requests to he UAAF to authenticate the user, authorize/deny

network access, and retrieve user-specific access configuration parameters

• Typically implemented as RADIUS client if the NACF is a RADIUS server.

• Connectivity Session Location Repository Function (CLF):• Registers association between the IP configuration of the CPE and

access transport characteristics, line identifier, IP edge identity, geographical location, etc.

• Provides user network profile information to the RACS. • Provides location information to TISPAN NGN core subsystems

30 © NOKIA NGN - HUT.PPT /13-04-2005 / Miguel. An. Garcia

NASS architecture (3)• User Access Authorization Function (UAAF):

• Performs user authentication and authorisation based on user profiles• Collects accounting data

• Profile Database Function (PDBF):• Stores the user network profile, containing

• User identity• Supported authentication methods• Keys

• Can be co-located with the UPSF• Customer Premises Equipment Configuration Function (CPECF):

• Provides the CPE with additional initial configuration information (firewall, diffserv packet marking, etc.)

• Customer Network Gateway (CNG):• Single point of entrance in the customer’s network (e.g., ADSL router)• Participates in line and access authentication

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31 © NOKIA NGN - HUT.PPT /13-04-2005 / Miguel. An. Garcia

The Service layer in NGN

Other netw

orksOther

subsystems

Core IMS

PSTN/ISDN Emulationsubsystem

User E

quipment

Service Layer

Transport Layer

Transfer Functions

Resource and Admission Control

Subsystem

Network Attachment Subsystem

Applications

Userprofiles

32 © NOKIA NGN - HUT.PPT /13-04-2005 / Miguel. An. Garcia

Service Layer• Modular Subsystem design• Two subsystem targeted in NGN Release 1:

• PSTN/ISDN Emulation Subsystem (PES)• Emulates the PSTN/ISDN, users don’t notice the change• Support for legacy equipment including black phones

• PSTN/ISDN Simulation Subsystem (a.k.a. IMS)• Multimedia terminals, new services based on the IMS model.• Includes PSTN/ISDN simulation services (similar to the PSTN/ISDN

Supplementary Services)

• Other subsystem may come in future NGN releases• Streaming Subsystem• Content Broadcasting Subsystem• Others as needed

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33 © NOKIA NGN - HUT.PPT /13-04-2005 / Miguel. An. Garcia

The IMS in NGN

Other netw

orksOther

subsystems

Core IMS

PSTN/ISDN Emulationsubsystem

User E

quipment

Service Layer

Transport Layer

Transfer Functions

Resource and Admission Control

Subsystem

Network Attachment Subsystem

Applications

Userprofiles

34 © NOKIA NGN - HUT.PPT /13-04-2005 / Miguel. An. Garcia

IMS architecture in NGN

Other IP N

etworks

IP Transport (Access and Core)

T-MGF

I-BGF

AS

UPSF

P-CSCF

I/S-CSCF

BGCF

SLF

ChargingFunctions

IWF

« Core IMS »

Mw

Mw/Mk/Mm

Mr

Mg

Mj

Mi

Mp MnGm

Gq’

ISCCx Dx

DhSh

Ic

Rf/Ro

Rf/Ro

Ib

Ia

Id

PSTN/ISD

N

SGFMRFC MGCF

MRFP

Resource and Admission Control Subsystem

Network Attachment Subsystem

If

Ie

MwIBCF

Mk

Mk

UE

Ut

NetworkInterconnections

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35 © NOKIA NGN - HUT.PPT /13-04-2005 / Miguel. An. Garcia

NGN impacts to IMS• IMS can be mostly reused, as specified by 3GPP, due to its large access

independence• A few changes are required:

• NAT traversal support in various points• Relaxation of IMS constraints:

• SIP compression is no longer mandatory• SIP timers are not “wireless” specific• SIP preconditions (183, PRACK, UPDATE) are no longer

mandatory• Support for ADSL access in P-Access-Network-Info header

36 © NOKIA NGN - HUT.PPT /13-04-2005 / Miguel. An. Garcia

IMS architecture (1)• Call Session Control Function (CSCF):

• Establishes, monitors, supports and releases multimedia functions• Three types of CSCFs: P-CSCF, I-CSCF, S-CSCF (same as in 3GPP

IMS)• But P-CSCF contains also:

• Application Level Gateway (ALG) to interface NAPT• Interfaces the NASS to retrieve user’s physical location

• Media Gateway Control Function (MGCF):• Controls a T-MGW• Converts ISUP to SIP• Functionality is equal to the 3GPP IMS MGCF

• Multimedia Resource Function Controller (MRFC):• Controls an MRFP• Together with the MRFP provides conference services, announcement

playback, and media transcoding• Functionality is equal to the 3GPP IMS MRFC

• Breakout Gateway Control Function (BGCF):• Selects the network in which PSTN breakout is to occur• Or selects the MGCF • Equal to the 3GPP IMS BGCF

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37 © NOKIA NGN - HUT.PPT /13-04-2005 / Miguel. An. Garcia

Architecture for IMS ASFs

UPSF

IMS core component

Transport Layer

S-CSCF

OSA SCS

SIP-ASIN SCF OSA AS

Sh

ShSi

Cx ISC

OSA APIINAP

Dx

IM-SSF

SLF

Dh

38 © NOKIA NGN - HUT.PPT /13-04-2005 / Miguel. An. Garcia

Application Server Functions• TISPAN NGN imports three types of ASFs from 3GPP IMS:

• SIP AS:• Native application server for newly developed services• May act as a SIP User Agent, SIP proxy, SIP 3rd party call controller

or SIP Back-to-back User Agent (B2BUA).• IP Multimedia – Service Switching Function AS (IM-SSF AS):

• Gateway to legacy Intelligent Network services executed in a Service Control Point (SCP)

• Open Service Access Service Capability Server AS (OSA SCS AS): • Gateway to legacy OSA services executed according to the

OSA/Parlay framework

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39 © NOKIA NGN - HUT.PPT /13-04-2005 / Miguel. An. Garcia

PSTN/ISDN Simulation Services• ETSI TISPAN considers two types of IMS services:

• Basic PSTN/ISDN Simulation Services:• Similar (but not equal) to PSTN/ISDN Supplementary Services• Unlike in the PSTN, not all these services require network support• Services must interwork with the similar PSTN/ISDN supplementary

service and 3GPP supplementary service• Multimedia services:

• New services, e.g., presence, multimedia instant messaging, SIP services that do not require extra standardization effort

• PSTN/ISDN Simulation Services defined in NGN Release 1 with three priorities:

• Mandatory services• Strictly recommended services• Optional services

40 © NOKIA NGN - HUT.PPT /13-04-2005 / Miguel. An. Garcia

PSTN/ISDN Simulation Services (2)

Call Forwarding No Reply (CFNR)Communication Forwarding on no Reply (CFNR)

Recommended

Call Forwarding Busy (CFB)Communication Forwarding on Busy user (CFB)

Recommended

Call Forwarding Unconditional (CFU)Communication Forwarding Unconditional (CFU)

Recommended

Call Diversion (CDiv)Communication Diversion (CDiv)Recommended

Anonymous Call Rejection (ACR)Anonymous Communication Rejection (ACR)

Mandatory

Malicious Call Identification (MCID)Malicious Communication Identification (MCID)

Mandatory

Connected Line Identification Restriction (COLR)

Terminating Identification Presentation (TIR)

Mandatory

Connected Line Identification Presentation (COLP)

Terminating Identification Presentation (TIP)

Mandatory

Calling Line Identification Restriction (CLIP)Originating Identification Restriction (OIR)Mandatory

Calling Line Identification Presentation (CLIP)

Originating Identification Presentation (OIP)

Mandatory

Equivalent Supplementary Service

Simulation ServicePriority

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41 © NOKIA NGN - HUT.PPT /13-04-2005 / Miguel. An. Garcia

PSTN/ISDN Simulation Services (3)

Advice of Charge (AoC)Advice of Charge (AoC)Optional

Conference Calling (CONF)Conferencing (CONF)Optional

Message Waiting Indicator (MWI)Message Waiting Indicator (MWI)Recommended

Follow Me (FM)Follow Me (FM)Recommended

Completion of Calls to Busy Subscriber (CCBS)

Completion of Communications to Busy Subscriber (CCBS)

Recommended

Outgoing Call Barring (OCB)Communication Barring (CB)(Outgoing CB, Selective Outgoing CB,

Incoming CB)

Recommended

Call Hold (HOLD)Communication Hold (HOLD)Recommended

Call Waiting (CW)Communication Waiting (CW)Recommended

Call Forwarding on Mobile Subscriber Not Reachable

Communication Forwarding on Not-Logged In (CFNL)

Recommended

Call Deflection (CD)Communication Deflection (CD)Recommended

Equivalent Supplementary Service

Simulation ServicePriority

42 © NOKIA NGN - HUT.PPT /13-04-2005 / Miguel. An. Garcia

PSTN/ISDN Simulation Services (4)

Trunk Hunting (TH)Optional

Explicit Call Transfer (ECT)Explicit Communication Transfer (ECT)Optional

Direct Dial In (DDI)Direct Dial In (DDI)Optional

Inhibition of Incoming Forwarded Communications (IIFC)

Optional

Fixed Destination CommunicationOptional

Closed User Group (CUG)Closed User Group (CUG)Optional

Equivalent Supplementary Service

Simulation ServicePriority

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The PSTN/ISDN Emulation Subsystem (PES)

Other netw

orksOther

subsystems

Core IMS

PSTN/ISDN Emulationsubsystem

User E

quipment

Service Layer

Transport Layer

Transfer Functions

Resource and Admission Control

Subsystem

Network Attachment Subsystem

Applications

Userprofiles

44 © NOKIA NGN - HUT.PPT /13-04-2005 / Miguel. An. Garcia

PES principles

• The PSTN/ISDN Emulation Subsystem replaces the classic PSTN/ISDN without being noticed by end users

• Provides full support for legacy terminals and services• Two PES implementations are possible:

• Based on a monolithic Softswitch (scope TISPAN NGN R1)• Based on a distributed IMS (scope TISPAN NGN R2)

• In both cases, the call control protocol is SIP-I (SIP encapsulating ISUP bodies)

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PES monolothicarchitecture

Distributor

Service A

Service B

Service C

MasterCustomer

Data

CustomerLocation

TrunkRouting

Service 1

Service 2

Service 3

PSTN/ISDNServicesAGCF TGCF

SGW

AGF

S/T

Z

AS

MGF

e

A-BGF I-BGF

RACS

IN

PSTN/

ISDN

RGW

Gq’

TopologyHiding

Gateway

OtherNGN’s

OtherNGN’s

PSTN/ISDNEmulationSubsystem

Transport

ba

a

c

f

g

h

j

i

AGCF

LocalData

AGF

46 © NOKIA NGN - HUT.PPT /13-04-2005 / Miguel. An. Garcia

PES monolithic architecture (2)• Access Gateway Function (AGF):

• Provides a gateway functionality to:• Analog terminals connected to an analog interface• ISDN terminals connected to a Basic Rate Interface (BRI)• ISDN terminals connected to a Primary Rate Interface (PRI)• Residential Gateways

• Typically located in the access network• Access Gateway Control Function (AGCF):

• First point of contact for AGF• Interacts with the RACS• Does ISUP (encapsulated in SIP) to H.248 conversion

• Residential Gateway (RGW):• Interface analog terminals and AGF

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IMS-based PES architectureO

ther IP Netw

orks

IP Transport (Access and Core)

T - MGF

I- BGF

UPSF

P - CSCF

I/S - CSCF

BGCF

SLF

ChargingFunctions

IWF

PES

Mw

Mw/Mk/Mm

Mr

Mg

Mj

Mi

Mp Mn

GmGq

ISC

Cx Dx

Dh

Sh

Ic

Rf /Ro

Rf /Ro

Ib

Ia

Id

PSTN

/ISDN

SGFMRFC MGCF

MRFP

Resource and Admission Control Subsystem

Network

Attachment

Subsystem

If

Ie

Mw

IBCF

Mk

Mk

Other services

(Simulation and MM services...)

PSTN/ISDN Emulation

Application Servers

Rf /Ro

MG

ZZ

ZZ

GW

S/TS/T

S/TS/T

AGCF

Gq

If

P1

P2

P3

48 © NOKIA NGN - HUT.PPT /13-04-2005 / Miguel. An. Garcia

IMS-based PES architecture• Reuse of IMS for providing PSTN/ISDN Emulated Services

• Including all the CSCFs, BGCF, MRFP/MRFC, MGC, MGW, and ASF• With the addition of a few components (e.g., AGCF, GW, etc)• Gateways may need to register terminals (SIP registration)

• Uses SIP-I as a call control protocol• SIP encapsulating ISUP bodies• Addition of SIP INFO method (RFC 2976) for mid call ISUP delivery

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ETSI TISPAN NGN arch. for DSL access

Resource and Admission Control Functionality

RACS

Based on 3GPP IMS IP Connectivity Access Network And related functionality

Network AttachmentFunctionality

NASS

Other Multimedia Components …

Streaming Services (RTSP based)

Applications

Core transport NetworkAccess Transport

Network

IP

UserProfiles

Other Networks

PSTN / ISDN Emulation(SIP-I based)

TGW

BGW

RGW MGF

PSTN/ISDN

Access Node

EdgeRouter

RACS

IP Multimedia Component (Core IMS )

(SIP based)

IP EdgeNode

L2TF

A-BGFARF

C-BGF

50 © NOKIA NGN - HUT.PPT /13-04-2005 / Miguel. An. Garcia

Conclusion• NGN networks will provide access to services over fixed broadband

connections• The architecture is layered: Service layer and Transport layer• The architecture is modular: Different subsystem added on demand• ETSI TISPAN NGN Release 1 will offer two subsystems:

• PSTN/ISDN Emulation Subsystem (PSTN/ISDN replacement)• PSTN/ISDN Simulation Subsystem (Core native IMS)

• ETSI TISPAN NGN Release 1 standardization will be finished at the end of 2005