To: risk-averse who wrote (175 ) 6/6/1998 1:35:00 PM From: risk-averse Read Replies (1) | Respond to
FROM rocketeer1 Saturday, Jun 6 1998 1:17PM ET
Reply # of 11420
Global Telephony
June 1998 One Final Word
Resources on the Net
ATM's invisible future
Could IP make ATM so transparent that it disappears?
JOHN WILLIAMSON, Senior Technology Editor
So far as standardization is concerned, asynchronous transfer mode (ATM)
looks to
be firing on all guns. By the time a meeting of the ATM Forum opened in
Berlin in
April, no less than 87 specifications covering various aspects of the
fast packet
switching technology had been agreed and ratified.
Some of these specifications have been on the books for quite some time.
A core set
of ATM standards had been laid down in what is known as the Anchorage
Accord
in mid-1996. This approved a basic set of standards needed for the
development,
implementation and management of multiservice ATM networks. Subsequent
meetings have built on this kernel.
In Berlin, for example, the ATM Forum was looking at items as diverse as
a
25-Mb/s ATM residential interface; the preparation of the extant inverse
multiplexing over ATM standard for submission to the International
Telecommunication Union; wireless ATM architectures; ATM routing and
addressing management; the interoperation of different ATM networks;
guaranteed
frame rate; interoperation with H.323 terminals; and the controversial
idea of
native-mode connectionless ATM.
Given the scope of this body of specifications and the potential
benefits arising from
deployment of the technology-the ability to accommodate mixed-media
traffic, very
high bandwidth and scalability, to list just three-it is perhaps
surprising that ATM
has so far made such a modest impact in the marketplace.
Or are appearances deceptive? True enough, an important part of the ATM
Forum's work is carried out by three market awareness committees,
suggesting that
much of the world is not yet beating a path to ATM's door. However, as
the forum
points out, users may be unaware (and possibly unconcerned) that they
actually are
using ATM. For example, many telephone company frame relay services have
ATM backbones, and most Internet protocol (IP) traffic runs over ATM
backbones.
It could be argued that this lack of visibility is a measure of ATM's
success-the
technology is transparent and supports everything, and users are none
the wiser.
One thing that may be muddying the waters for "invisible" ATM is the now
highly
"visible" world of IP. Some network architectures envisage ATM cells
transporting
IP packets over a digital subscriber line (xDSL) or synchronous digital
hierarchy
(SDH). However, it is possible to run IP over SDH or xDSL without the
intervention of ATM. And it's not unreasonable to imagine some operators
might
want to avoid the additional overhead of ATM.
Indeed, according to a new report from the U.K.'s Ovum consultancy,
entitled "The
Future of Broadband Networking: ATM vs. TCP/IP," ATM will not be the
leading
technology in the future of broadband networking.
"For many years the orthodox view of the development of broadband
networking
has been that it would use ATM transmission and switching," says John
Matthews,
principal consultant at Ovum and the report's author. "However, the rise
of the
Internet and enhancements to the TCP/IP protocol suite has changed that
orthodoxy,
and the future of broadband will not be dominated by ATM. Growth of the
Internet
and improvements to the TCP/IP protocol suite make it more geared to
cope with
multimedia, broadband and real-time communications."
IP will be the dominant protocol for broadband wide area networking by
2002,
Ovum says. Usage of both ATM and TCP/IP will grow rapidly, but by 2002,
usage
of TCP/IP will exceed usage of other protocols.
As you'd expect, members of the ATM Forum have a radically different
take on
things. They say that with just IP over synchronous transmission you
need very big
routers whose cost-effectiveness is questionable. More importantly,
without the
addition of some ATM-like connection-oriented attributes, IP does not
have the
same ability to provide qualitative and quantitative service guarantees
or to control
granularity, and does not readily facilitate service differentiation.
The forum also
points out that carriers need ATM to be able to provide multiservice
offers to their
customers.
For what it's worth, my money's on the invisible supporting the visible.
Global Telephony
July 1998
Coming in the next issue!
Carrier:
Customer Care/OSS
Enterprise:
Videoconferencing
Special Feature:
Latest in satellite communications
FEATURES
Customer Care/OSS
By George Lawton
The Internet is becoming another key tool for carriers to use when it
comes to
customer care. Various developments are allowing carriers to improve
customer
support and communication via the Internet and it gives customers access
in real-time
to billing information to be able to check for fraud or to do more
detailed immediate
analyses of expenses or even monitor services. In short, the Internet is
creating a
better environment for customer care and does it cheaper.
Videoconferencing
By Jeff Baskin
Videoconferencing is one of those technologies that have been available
for years. But
recent advances such as a high-speed video coder, systems that can
deliver video
through the PBX, and networks able to handle more bandwidth are likely
to soon
make desktop videoconferencing commonplace. As the quality improves,
more
businesses are finding ways to use videoconferencing and the industry
seems poised to
take off.
Latest in satellite communications
By John Williamson
Satellites in geostationary orbit (GEO) have traditionally been used to
support
long-haul, thick-route communications and broadcast services. More
recently, as
spacecraft increased in power, and higher radio frequencies were brought
into use,
very small aperture terminal (VSAT) technology was harnessed to support
thin-route,
point-to-point and point-to-multipoint applications. According to market
research
concern Frost & Sullivan, VSAT networks will continue to provide private
corporations with solutions which bypass traditional public telecoms
operators.
Meantime, new constellations of low earth orbit (LEO) satellites are
being constructed
to provide in-fill cellular, narrowband fixed access, and broadband
multimedia
services
