One more folks from Rocketeer1:
To: rocketeer1 (11420 )
From: rocketeer1 Saturday, Jun 6 1998 1:47PM ET
Reply # of 11523
June 08, 1998, TechWeb News Carrier Flash Point -- Defining IP-PSTN Links
By Jeff Caruso
"We want to make the phone the most ubiquitous IP device
in the world," AT&T CEO Michael Armstrong recently said.
Achieving that goal-and thereby joining the Internet to the public switched
telephone network (PSTN)-is tantamount to overhauling the Internet, and the
Internet Engineering Task Force (IETF) is working hard to make that happen.
This week, the IETF's Differentiated Services (Diffserv) working group will hold
an interim meeting aimed at accelerating specification and framework documents
so they can be submitted for consideration as requests for comment (RFCs) next
month.
Differentiated services would let traffic be grouped into different classes of
service. If users are willing to pay more, their traffic could potentially get
through the Internet faster. This capability would first be applied to data, but
real-time traffic could follow.
The IP Telephony (Iptel) working group, meanwhile, is readying its first draft
document on service frameworks, to be submitted as an RFC next month. Iptel
hopes to have a draft document defining voice-call-processing syntax ready by
August.
There are several other working groups-some focused on points of interaction
between the Internet and the circuit-switched telephone network; others focused
on making the Internet more robust for real-time communications (see chart).
Although there is no single overarching framework, these efforts pro-mise to
redefine the Internet.
"The problem is making the Internet work for voice and business applications,
and we're treating parts of the problem separately," said Fred Baker, a Cisco
fellow and co-author of several draft documents in this area.
Not all the standards work that emerges will necessarily be useful for IT
managers, but other standards will, said Tom Nolle, president of CIMI Corp., a
consultancy. "Technical people are bad judges of market conditions," he said. In
the end, the market will decide what is useful and what is not.
Carriers such as AT&T and MCI are watching the IETF activities closely, and
plan to integrate the useful standards into their emerging communications
platforms as soon as they solidify.
AT&T, in particular, has been touting its advanced network services platform,
formerly code-named GeoPlex, as a way to offer services in both the voice and
data realms. The software, running on central office equipment, is flexible
enough that new standards can be integrated easily, said George Vanecek, chief
scientist at AT&T Labs.
Standards like Diffserv could be integrated into the platform or into services that
run on top of it, he said. Unified messaging-that is, making voice messages, faxes
and E-mail messages available in one place-is viable with the software.
But even with advances in standards, carriers will be reluctant to abandon
circuit-switching equipment. "Right now, jumping off the phone network is like
leaving a civilized society and going into a no-man's land," Vanecek said.
AT&T's Armstrong said that "you can do most of what you want to do on the
Internet from a phone," such as check E-mail and perform simple Web browsing.
Before that can happen, though, the gateways between the two networks need to
be standardized and made scalable, said Rick Wilder, senior manager of Internet
technology at MCI.
Service providers need to make sure their own infrastructures are ready, he said.
Routers must have the right queuing algorithms to give priority to real-time
traffic, and voice traffic coming from the Internet has to be presented to voice
switches at precisely the amount of bandwidth the switches expect.
Service providers are keen on using standards, and Diffserv was launched in part
to prevent Cisco's proprietary committed access rate (CAR) from becoming a de
facto standard, said Eric Crawley, consulting engineer at Argon Networks. Both
CAR and Diffserv use the type-of-service bits in the IP header to specify which
packets deserve better quality of service.
Although Resource Reservation Protocol once showed promise for requesting and
getting quality of service, service providers balked because it's geared toward
individual flows, and therefore doesn't scale, Crawley said.
Copyright r 1998 CMP Media Inc. |
