Download PSTN-Internet Convergence with QoS and Wireless Applications

Trends in Network Evolution
Igor Faynberg, Ph.D.
Hui-Lan Lu, Ph.D.
Bell Labs, Lucent Technologies
Multimedia Convergence Workshop
Geneva, 2002
Slide 1, hlu & faynberg
Outline

Introduction
 Internet
–
–
–
–
Original Requirements
Architectural Principles
Hourglass model
New requirements

Some observations
 An evolvable solution
Slide 2, hlu & faynberg
An Increasingly Connected World



About a billion wireless subscribers in
the world today, growing about 20% per
year
3
Billions

A century to install the world’s first 700
million phone lines; 700 million more
lines over the next 15-20 years
About 300 million Cable TV subscribers
in the world today, growing about 6%
per year
More than 400 million Internet users in
the world today, growing about 20% per
year
90 million km of fiber deployed in 2000
– enough to circle the globe 2250 times
– bringing the installed base to about
400 million km
Global Access Lines
Wireless
Cable
Wireline
2
1
0
1958
1000
Millions

1978
1998 2005
Global Internet Users
800
600
400
200
0
1995
Slide 3, hlu & faynberg
2000
2005
Requirements for the Original Internet
high
importance  Existing networks must be interconnected with an
effective multiplexing technique
 The interconnected network must continue to
function despite partial network failures
 The resultant architecture must
low
importance
Slide 4, hlu & faynberg
– Support multiple types of communications
applications
– Accommodate a variety of networks
– Permit distributed management of its resources
– Be cost effective
– Permit host attachment with a low level of effort
– Be able to account for the resources used
The Internet
A basic component is routers, which
interconnect distinguishable networks by
storing and forwarding packets
...
IP Network 1
Gateway
IP Network 4
IP Network 2
IP Network 3
Slide 5, hlu & faynberg
Internet Architectural Principles (RFC1958)

Emphasize intelligence at the edges (i.e., fate sharing),
distributed processing, dynamic (versus static) solutions,
and modularity
 Support accommodation of multiple network types
 Are inherently hostile to the needs of Internet-wide realtime
multimedia applications
 Are not a religion (RFC 1958 is informational)
Slide 6, hlu & faynberg
The End-to-End Argument
The function in question can completely and correctly be
implemented only with the knowledge and help of the
application standing at the end points of the communication
system. Therefore, providing that questioned function as a
feature of the communication system itself is not possible.
(Sometimes an incomplete version of the function provided by
the communication system may be useful as a performance
enhancement.)
(J. H. Saltzer et al., “End-to-end Arguments in System Design”)

Move functions up and out
 Make the network as transparent as possible
Slide 7, hlu & faynberg
The Internet Hourglass
• A single data delivery
•
•
•
service at network layer
maximizes interoperability
and minimizes the number
of service interfaces
Minimum function (besteffort packet forwarding) at
network layer allows the
network to scale easily
A single global address
space is accessible to all
Shielding network details
from upper layers fosters
application innovation
email WWW telephony...
SMTP HTTP RTP...
TCP UDP…
IP
802.2 PPP…
CSMA SONET...
copper fiber radio...
(Source: Steve Deering’s presentation
at the IAB Plenary, 51st IETF )
Slide 8, hlu & faynberg
Out of Shape?
email WWW telephony...
email WWW telephony...
email WWW telephony...
SMTP HTTP RTP...
SMTP HTTP RTP...
SMTP HTTP RTP...
TCP UDP…
TCP UDP…
TCP UDP…
IP + mcast
IP
IP
ATM
+ QoS +...
802.2 PPP…
802.2
802.2 PPP…
CSMA SONET...
CSMA SONET...
CSMA SONET...
copper fiber radio...
copper fiber radio...
copper fiber radio...
(Source: Steve Deering’s presentation at the IAB Plenary, 51st IETF )
Slide 9, hlu & faynberg
Factors Changing the Internet

Growing size of the routing table
 More-demanding applications, such as
– Media streaming
– Multimedia conferencing

New types of endpoint devices, such as
– Personal digital assistants
– Cell phones
– Appliances

Assured operation in an untrustworthy world
 Service provider service differentiation
 3rd party intervention (e.g., wiretapping)
 Less-sophisticated users
Slide 10, hlu & faynberg
Some Observations

IP has become the public UNI for networking-service access.

Separate specialized networks are evolving to multi-service
networks that have a packet/optical core.

MPLS is a key technology to enable the packet core to deliver
better- than-best-effort, manageable and billable services.

The synthesis of the Internet philosophy (Intelligence only at
the edges) and Telecom philosophy (Intelligence only at the
network) is Global Services through coexistence and
cooperation of the Intelligence in Networks with the
Intelligence at the Edges!

National and international regulations are adapting to address
issues on, for example, open access, fair competition,
intellectual properties rights, security and privacy.

The standards organizations should cooperate in defining
interfaces and building blocks for ubiquitous intelligence.
Slide 11, hlu & faynberg
An Evolvable Solution
--Intelligence in every layer
Control
Bearer
Application
Layer
Application
Services
Internet
Service Control
Layer
Softswitch
Control
IP Service
Switching
Network Transport
Layer
Media
Gateways
PSTN
Broadband
Access
Multiservice
Packet Switching
RAS
X
DSLAM
GbE
Frame/
ATM
Access
Network
CPE
Wireless
Slide 12, hlu & faynberg
X
Metro Optical
X
X
X
X
X
Optical Core
X
Core network
X
X