Basic NGN Architecture
&
Principles
Keith G Knightson
Canada
1
NGN Architecture: Initial Considerations
•
NGN difficult to define in absolute terms of:
• specific technologies
• specific architecture
• topology
•
Need to avoid technology traps
•
Identify high-level paradigms
• separation of concerns (and related functions)
• technology agnostic
•
Identify emerging NGN-generic issues
• Architectural principles
• Need for NGN models to show separation
of concerns/functions
2
NGN Definition
Next Generation Network (NGN): 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.
ITU-T Recommendation Y.2001
3
What’s old: Vertically-Integrated Networks
Pre-NGN
Video
Services
(TV, movie, etc)
Telephone
Services
Data
Services
(WWW,
e-mail, etc)
Video
Services
Network
Telephone
Services
Network
Data
Services
Network
Policy Area 2
Policy Area 3
Policy Area 1
4
What’s New: Horizontally-Integrated Networks
NGN - Convergence Model
Video Services (TV, movie, etc)
Data Services (WWW, e-mail, etc)
Telephone Services
NGN Services
Point to point, Point to multipoint, Multipoint to multipoint
NGN Transport
Point to point, Point to multipoint, Multipoint to multipoint
ITU-T Recommendation Y.2011
5
Networking Aspects
Network of Service
Platforms
NGN
Telecomm
Services
Separation
Transport
Network of Transport
Components
6
Re-distribution of Service Intelligence
Migration of
Service Intelligence
Access
User
Domain Domain
Core
Domain
Access
Domain
User
Domain
No 1:1 location correspondence between a switching component
and a service component
7
Service Separation
Application
Server
Users
Application
Server
Switched
Core
Packet
Network(s)
Switched
Access
Network(s)
Transport
Protocol
Interworking
Single point
Or
Distributed
Application
Switched
Access
Network(s)
Users
Transport
Protocol
Interworking
Transport only provides transfer between service platforms
8
Decoupling Services from Transport Network
Service Management
Service
Instance
Application
Services
Wholesale
Resource
Management
AAA
Billing
Service infrastructure
Retail
Service Management
Transport
Services
Service
Instance
Resource
Management
AAA
Billing
Settlement
Service infrastructure
U
Subscriber
A10
NAP
NSP/ASP
Architectural and Business implications involved
9
Protocol Architectures: Layering Considerations
Service Mapping
&
Protocol Translation
Protocol X
Service Mapping
&
Adaptation
Protocol Z
Peering Relationship
Layering Relationship
Protocol Y
No particular prescribed protocol hierarchy:
Any X over any Y
Layer Network see G.805/809
10
Protocol Architectures: Convergence Layer
Layer n + i
Layer n + 2
Layer n + 1
Set of application/service
Functions (Fn+1….Fn+i)
Layer n = IP
“Primary” and
“ubiquituous”
“convergence”
Protocol
Layer
Layer n - 1
Set of Transport
Functions (Fn….Fn-j)
Layer n - 2
Layer n - j
G.805/G.809 principles apply
11
NGN: IP as the Network Layer Protocol
(Any/All Applications
e.g. voice , data , video)
Services
Everything over
Internet Protocol
(IP)
Transport
Scope
Of
“NGN”
Over Everything
(Any & All Network technologies)
Two Architectural Domains
(Potentially two business and policy domains)
12
Simplified Protocol Architecture
Non-IP
Services
Applications
Application Helpers (UDP, TCP, RTP, etc)
IP
MPLS or shim
(Optional)
Ethernet
LAN or MAN
Optical Bit Transport
ADSL, Cable, etc
Not exhaustive, other combinations possible, but….
Convergence based on IP is the architectural trend
13
Transport Convergence
Past : Seper. of Voice & Data Transp.
Circuit Switch.
Access Capa.
Circuit Switch.
Transp. Capa.
Packet Switch.
Transp. Capa.
Future : Integration of V & D Access andTransp.
Near Past : Sep. of V & D Access
Circuit Switch.
Access Capa .
Packet Switch.
Access Capa .
Packet Switch.
Transp. Capa.
Present : Integration of V & D Transport
Circuit Switch.
Access Capa.
Packet Switch.
Access Capa.
Circuit Switch.
Transp. Capa .
Packet Switch.
Transp. Capa .
Packet Switch.
Access Capa.
Circuit Switch.
Transp. Capa.
Packet Switch.
Transp. Capa .
14
Y.2011: Basic Functional Separation
Management Plane
Control Plane
User Plane
NGN Service Stratum
Management Plane
Control Plane
User Plane
NGN Transport Stratum
15
Y.2011: Basic Functional Architecture Considerations
Application, Middleware & Baseware services
Services
Resources
NGN
Service
NGN
Transport
Service
Management Functions
Transport
Management Functions
Service
Control Functions
Transport
Control Functions
Transfer Functional Area
16
Basic Functions
Service stratum
Service stratum
Application functions
Application functions
Customer
Customer
DB
DB
functionsfunctions
Service
Service and
and
control
control
functions
functions
Media
handling
functions
Tra nsport adaptation functions
Customer
functions
Customer
functions
Transport adaptation functions
Network
entry
functions
Access
Access
Transport
Transport
functions
functions
Network
entry
functions
Access
Network
UNI Transport
Access
stratum Network
Transport
entry
entry
Transport
functions
functions
functions
functions
UNI
Core Transport
Core Transpo rt
functions
functions
Media
Gateway
functions
handling
functions
Other
Other
networks
networks
Other
Other
networks
networks
Gateway
functions
NNI
Core Transport
Core Transport
functions
Control
functions
Media
Note: Charging and billing functions and Management functions are applied to both Service and Transport strata
Transport stratum
NNI
Control
Media
Note: Charging and billing functions and Management functions are applied to both Service and Transport strata
17
Y.FRA - Functional Requirements & Architecture
(may include own Authentication, Authorization and Accounting)
A-2
Application Gateway Function
S -9
S -17
User Profile DB Function
LS Function
Management Function
S -1
Terminal
Function
S -18
Session Control Proxy
Function
T-16
T-18
T-6
AMGF
Management
S -19
Media Resource Control Function
Transport Adaptation
Transport Resource / Policy Control Function
T. Authentication
&Authorization
Function
T-20
T.Network Access
Control Function
T-4
T.Network Access
Process Function
T-8
Mobility Support
Function
T-11
Media
Resource
Processing
Function
AGCF
S -12
MGCF
other IP MM
Network
(e.g. IMS)
T-12
SGF
T-3
Internet
T-13
T-15
Transport
Resource &
Enforcement
Functions
PGF
Traffic
Measurement
Function
T-1
Packet Transport Function
Other NGN
T-9
Transport
T-7
Access Relay
Function
PGCF
Session Control Function
S -11
Session & Call Control
S -4
S.Authentication & Authorization Function
S -10
Registration
Function
S -13
Network Border
Application
Application Server Function
A-1
PSTN/ISDN
TMGF
Scope of NGN
All lines of this type attach to the corresponding input line at the CCF within
session & call control
Connection point
18
Component/packaging viewpoints
Applications
Based on
3GPP IMS
IP Connectivity
Access Network
And related functionality
User
Profiles
Other Multimedia
Components …
Streaming Services
(RTSP based)
IP Multimedia
Component (Core IMS )
(SIP based)
Legacy
Terminals
Customer
Networks
GW
Network Attachment
Functionality
NASS
Access Transport
Network
Resource and Admission
Control Functionality
RACS
Other Networks
PSTN / ISDN Emulation
(SIP-I based)
Core transport
Network
NGN
Terminals
3GPP IP-CAN
3GPP Terminals
19
IMS Architecture
AS
Other IP Multimedia Networks
PSTN
Sh
ISC
Mm
MGW
BGCF
PSTN
HSS
(AAA+DB)
CSCF
Mk
Mj
BGCF
Mn
Cx
Mw
Dh
Mi
Mg
Mb
MGCF
Mb
SLF
CSCF
Dx
MRFP
Mr
Mb
Mp
MRCF
Mb
IP Con nectiv ity Access Network
Mw
P -CSCF
Gq
Gm
UE
20
Application Server Function
(may include own Authentication, Authorization and Accounting)
A-2
Application Gateway Function
IMS
S-9
PSTN/ISDN
simulation function
S-4
User Profile DB Function
LS Function
Multi media function
S-1
Messaging function
Presence function
EMS
T-6
AMGF
Management
S-19
Media Resource Control Function
T-16
Transport Adaptation
Transport Resource / Policy Control Function
T-18 T. Authentication
&Authorization
Function
T-20
T.Network Access
T-7
Access Relay Control Function
T-4
Function
T.Network Access
T-15
Transport
Process Function
Resource &
T-8
Enforcement
Mobility Support
Functions
Function
T-11
Media
Resource
Processing
Function
AGCF
S-12
MGCF
T-1
Packet Transport Function
oth
N
(e
T-12
SGF
T-3
In
T-13
Traffic
M easurement
Function
O
PGF
Transport
Proxy
Function
PGCF
Session Control Function
S-11
S-18
Session Control Proxy
Function
Terminal
Function
NMS
S-17
S.Authentication & Authorization Function
S-10
Registration
Function
S-13
Session & Call Control
PSTN/ISDN
emulation function
Network Border
A-1
Application
Mapping To IMS
T-9
PS
TMGF
Scope of NGN
All lines of this type attach to the corresponding input line at the CCF
within session & call control
Connection point
21
“Generalized” Mobility
Device Mobilty Domain
User/Service
Mobilty Domain
Network
Legend :
Points of Attachment (POA) fixed or wireless
Communications Objects (mobile with transient binding to POA)
22
Transient Binding
Fixed/Cellular Mobility
Radio Access
Network
….
….
….
….
Base
Station
Controller
Dual Mode
Handset
Core
Mobile
Network
IP Access
Network
UMA
Network
Controller
WiFi
How to integrate with fixed VoIP service?
Cross Architectural impacts?
23
Co-existing/converging mobile and fixed
Radio Access
Network
….
….
….
….
Base
Station
Controller
UMA-enabled
Dual Mode
Handset
GSM/IMS Core
Service
Architecture
Tunnelled
IMS stack
WiFi
RG
….
….
….
….
GANC
(UMA)
Network
Controller
IP Access
Network
Native IP
Stack
VoIP
SIP
Server
IP
Core
Transport
SIP
Fixed/wireless Telephone
24
Scope and extent of Mobility levels
Service Level
Mobility
IMS
PSTN /
SS7
GMSC
HA
FA
FA
PDG
GGSN
Inter-Access Network
Level Mobility
Intra-Access Network
Level Mobility
Wide Area
FA
LMA
LMA
ESS
ESS
DVB-GW
SGSN
SGSN
RNC/BSC
AP
IPv4 MS
+ CCoA
AP
AP
IPv6 MS
+ CCoA
AP
AP
DVB-TX
BTS
RNC/BS
C
BTS
Intra-Access Network
Level Mobility
Local Area
MSC
RNC/BS
C
BTS
Intra-Access Network
RadioLevel Mobility
BTS
IPv4 MS
WLAN / WiMAX
DVB / ISDB-T
GPRS/UMTS
Data
Cellular
Voice
25
Home Gateway Functionality
Desktop PC
Network
Terminating
Unit
10/100
Base-T
Desktop PC
Customer
Premise
Network
Routing
Gateway
Set Top Box
Television
Other
Devices,
Appliances,
etc
Set Top Box
Television
….
….
….
….
IP
phone
QoS per device/terminal
26
Traffic shaping in Routing Gateway
RL
EF
AF1
RL
AF2
ASP
Access
AF3
AF4
BE
Classifier
RL
EF
Data In
AF1
Data Out
S
RL
RL
AF2
AF3
PTA
AF4
BE
RL
PPP Access (BE or AF)
PTA = PPP Termination Aggregation
RL = Rate Limiter
S = Scheduler
27
Summary of Relevant Work
•
Y.2001: NGN Overview
• NGN Definition, Characteristics & Subject Areas
•
Y.2011: General Reference Model
• Identify high-level paradigms
• Separation of concerns, services from networks
• Identify emerging NGN-generic issues
• Architectural principles
• OSI model relevance
• G.805 relevance
•
Y.FRA: Functional Requirements & Architecture
• Service control functions
• Transport control functions
• Mobility management functions
• Wireless and Fixed access
• IMS positioning
• Multi-terminal/multi-QoS Home Gateway
28
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