VoFR is part of a developing picture (info on LCI and US West contracts with ASND)
americasnetwork.com
June 15, 1998
By Annie Lindstrom
Voice over Internet protocol (VOIP) is turning lots of heads these days,
but its relative infancy as a technology has some business customers looking at
other ways put voice onto data networks.
Frame relay service providers and equipment suppliers confirm that more of
their customers are considering and implementing voice over frame relay
(VoFR) because it enables them to maximize the efficiency of their frame relay
networks by pumping voice calls to their branch offices over their data
networks rather than across the public switched telephone network (PSTN).
One big difference between VoFR and VOIP is the ubiquity of the networks
which support them. With the proper standards in place, VOIP will enable
everyone connected to IP networks or the Internet to converse with one
another. In general, VoFR users may converse only with other frame relay
users.
"VOIP can actually impact a bigger audience," says Rick Malone, principal of
Vertical Systems Group (Dedham, Mass.) "If there are half a million frame
relay ports in service, that's the cap on who you can reach. There are 20
million people on the Internet, so eventually there will be more voice over IP.
But I think it will take a while before it is the primary way that corporations run
their voice networks."
Malone says there will be about 46,000 VoFR ports installed worldwide by
the end of 1998, growing to 112,000 by 2000.
Popularity award
Interest in VoFR is rising. For about a year, VoFR has been the most popular
application tested at MCI's Richardson, Texas-based Developers Lab,
according to a company spokesman. The lab allows vendors and customers to
evaluate the real-world performance of potential equipment and services on a
piece of MCI's live network - which, for security's sake, does not carry
customer traffic.
Although MCI does not have a VoFR offering, the carrier helps its customers
engineer their networks to support VoFR by making sure they have specified a
high enough committed information rate (CIR) to carry the additional traffic and
by tuning their networks so that they have the appropriate sensitivity to delay,
says Edsel Garciamendez-Budar, director of broadband engineering for MCI.
"Voice, video and fax can all tolerate delay of a total of 50 to 150
milliseconds," says Andy Voss, vice president of marketing for Nuera, the San
Diego-based developer and manufacturer of the Access Plus family of
VoFR/IP gateways.
In most cases, MCI gets requests for help with VoFR from large customers
with complex frame relay networks. "A little more than a year ago, queries
about VoFR were an exception. Now it is becoming much more common,
especially for customers that have nailed down communities of interest,"
Garciamendez-Budar says.
LCI International (McClean, Va.) also reports a groundswell of interest in
VoFR. Customers who are expanding their networks are the most curious, says a company spokesman. "We just struck a deal with Ascend for B-STDX
9000 multiservice frame relay switches, which will enable us to better serve our
customers who want to do voice over frame relay," he says. "We are hearing
from customers more and more that they want that option available."
The impending merger between LCI and Qwest (Denver), which is building an
IP-based network, reportedly will not lead LCI to favor VOIP over VoFR.
"Qwest knows we have customers who are very comfortable with, and like the
cost efficiency of, frame relay," the spokesman notes.
Quality of Service
Even though many frame relay networks are already capable of supporting
VoFR and many customers are implementing the solution unbeknownst to their
service providers, several interexchange and local exchange carriers (IXCs and
LECs) are developing quality of service (QoS) offerings that will streamline
their customers' implementation of voice and video over frame relay. Frontier
Communications Services (Rochester, N.Y.) plans to roll out QoS for frame
relay by 1999, says Michael Holodnik, Frontier's product manger for frame
relay.[ASND contract?]
"More and more customers are looking at consolidating all of their services
across a single pipe," Holodnik says. "There is a certain technology leap they
need to take to move to ATM [asynchronous transfer mode] as well as higher
cost. Frame relay also provides a certain amount of security as well as discrete,
identified bandwidth between locations, which you might not be able to get on
an IP network or over the Internet."
"All of the real-time applications people are being told they need to go to ATM
for are quite doable over well-engineered frame relay networks," Voss adds.
US West is working with Ascend to enhance its frame relay offerings and offer
QoS by year's end, says Larry Floyd, group manager of data transport
services for US West !nterprise Networking Services. "We do think there is a
significant market with this," Floyd says.
Sprint Business (Kansas City, Mo.) is evaluating the merits of offering a VoFR
class of service later this year, because "we see things heading that way," says
a company spokesman.
Carriers are getting involved in VoFR to hold on to their customers, says
Andre de Fusco, vice president of business development for ACT Networks
(Camarillo, Calif.). ACT's NetPerformer product combines data, voice, fax
and video transmission over the same frame relay link. "I think carriers will get
involved because they are going to want to offer VoFR as a native service and
help their customers handle load, balancing and congestion issues," he notes.
"Today, every public network out there is carrying VoFR."
That includes satellite networks. GE Spacenet (McLean, Va.), Victory
Communications (Rio de Janeiro) and Comsat do Brasil (Sao Paulo) use
ACT's SkyFrame product to provide frame relay service via satellite to global
companies operating in parts of the world with underdeveloped
communications infrastructures, de Fusco says.
Standards stand up
The Frame Relay Forum last year adopted FRF.11, which specifies two voice
compression algorithms for VoFR products, says Mark Amick, frame relay
product manager for Adtran (Huntsville, Ala.). The two algorithms are adaptive
differential pulse code modulation (ADPCM), which compresses voice into 32
kbps of bandwidth, and the International Telecommunication Union's (ITU)
G.729, which employs an algorithm owned by a group known as the G.729
consortium, which compresses voice into 8 kbps of bandwidth. To date,
vendors such as Adtran have not embraced FRF.11, because ADPCM uses
too much bandwidth, and because vendors have to pay the consortium $7.50
per server port and additional fees to use the G.729 algorithm, Amick says.
Adtran's FSU 5622 frame relay access device (FRAD) and Atlas integrated
access device (IAD) support VoFR, using the ITU's G.723 standard for
VOIP which compresses voice into 6.3 kbps of bandwidth, Amick says.
"We use the VOIP algorithm because we want to be able to address VOIP,
but we think the biggest marketplace is VoFR," Amick says.
June 15, 1998 table of contents
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