ISDN...gets a new style
Can the technology shake its old image in favor of a new user-friendly attitude? DENISE
PAPPALARDO
If ISDN were a movie star, it would have appeared on Blackwell's best- and
worst-dressed list. At various points over its 20-year history, ISDN has been
hailed as a great achievement, capable of carrying voice, video and data over
a single connection. It has also been derided as a huge flop, virtually
impossible to install or understand.
How does it currently rate? Driven to a large extent by remote access applications (Figure 1), the
installed base continues to grow substantially (Figure 2).
The past year has brought a number of positive developments for the technology. Industry groups have
agreed on several key standards that should make ISDN easier to use, and ISDN equipment prices have
dropped. Overshadowing these advances, however, are new access technologies--including
asymmetrical digital subscriber line (ADSL), cable modems and 56 kb/s modems
A more casual approach
The future of ISDN depends on the ability to ease the ordering and equipment installation process for the
customer, says Kitty Weldon, senior analyst at The Yankee Group, Boston. Some customers will not use
analog modems to access the Internet because they demand more bandwidth, she says, adding that it's
not too late for ISDN to become a user-friendly service.
To simplify the ISDN deployment process, the North American ISDN Users Forum--a National Institute
of Standards and Technology group--and the National ISDN Council have developed a format for a
generic service profile identifier (SPID).
A SPID number, similar to a telephone number, needs to be entered into ISDN customer premises
equipment. Traditionally, each manufacturer's central office switch has interpreted SPID information
differently--which means customers have had to identify the type of switch that they were connecting to.
The NIC and NIUF formed a task force to simplify the process of configuring CPE. CO switch
manufacturers Ericsson, Lucent Technologies, Northern Telecom and Siemens worked with the task
force to devise the generic SPID format, which will be common to all switches. Most telcos are expected
to have implemented the generic SPID format by the end of the year.
Generic SPIDs will make it easier for users to establish ISDN service, says Garrett Jenkins, ISDN
industry liaison for BellSouth and NIC chairman. Customers can simply look at their equipment
instruction manual for complete SPID information. They will no longer need to know their CO switch
type. And large customers, value-added resellers and equipment vendors in multiple locations can use the
same procedure for each location, Jenkins said.
The generic SPID should also make ISDN more attractive to Internet service providers. Until now, the
inconsistency among CO switch manufacturers has made it difficult for carriers and ISPs to offer access
software to their customers, says Jeffrey Fritz, a telecommunications engineer at West Virginia University.
Incorporating generic SPID support into access software should help ISPs simplify their ISDN interface.
GTE completed its generic SPID implementation in September, notes Christine Christian, GTE's ISDN
program manager.
"The changes were [mostly] internal from a communications standpoint, including entry-order people,
facilities assignments and updating databases," says Christian. "Everyone who has worked with SPIDs
has welcomed the generic format. I would love to see the day when we don't have to use the term SPID
at all. Moving forward, our customers will not have to deal with the hassle of SPIDs."
The generic SPID is only the first of three steps that have been recommended by the SPID Task Force
to simplify the user's interface with the switch.
An ongoing plan addresses another ISDN pitfall. Currently, different switch manufacturers have different
methods of implementation of enhanced calling features--with each manufacturer requiring a different key
or a series of keys to be pressed to access a specific feature. The task force has recommended a solution
that would assign fixed feature identifier values to feature keys.
In the long term, SPID selection will be automatic. The switch will send the SPID to the terminal device,
eliminating the need for the user to manually enter the SPID.
Pacific Bell is already offering an ISDN Internet access package, dubbed Home Pack, that has automatic
SPID support. The company partnered with 3Com to develop the offering, which was formally
introduced at Comdex earlier this month. The package includes Web browser software for Pacific Bell
Internet access.
Ending mismatches
The NIUF is also working with carriers to develop a single form for ordering ISDN service.
"Traditionally, the ordering process has been ISDN's stumbling block," says Kieran Taylor, broadband
consultant at TeleChoice, Verona, N.J. Carriers and ISDN equipment vendors need to simplify the
ordering process and get that message to the market before ADSL and cable modems gain wide
acceptance, he says.
Currently, every interexchange carrier, local exchange carrier and anyone else offering basic rate ISDN
service uses a different order form.
AT&T, which frequently orders basic rate lines from other carriers, recognized the need for a common
and more simplified form, so it developed one. The form was presented to the NIUF for consideration
about a year and a half ago, says Dick Slezak, AT&T's managing director of global ISDN. The NIUF is
working to make AT&T's form acceptable for all carriers.
"We put as many basic rate ISDN lines onto our network register in the last eight months as we did in the
previous five years. A standard template makes sense," Slezak says.
GTE plans to adopt the NIUF's simplified order form, says Christian. "The latest revision from the NIUF
looks pretty clean," she says.
GTE believes it will be able to implement the unified order form by the end of the year. A single form will
be a key advantage to GTE because it deals with so many states and carriers, Christian says, adding that
the new form will enable the company to offer better service to its customers and shorten the time
between service ordering and deployment.
"The ordering codes for equipment manufacturers is a much bigger hurdle," Christian says.
ISDN CPE does not offer users standardized plug-and-play features, she says. To address this need, the
NIUF has developed the EZ-ISDN series of codes that specify how a line should be provisioned for use
with various end user devices (see sidebar)
New contenders
ISDN has some focused competition creeping up on it. ADSL and cable modems have been this year's
access buzz words, but service availability for these technologies is extremely limited and is mainly in the
testing phase.
Each technology offers advantages to users--although ISDN's main advantage now is that it is widely
available and that many of its kinks have already been worked out.
Like ISDN, ADSL uses twisted pair copper telephone cable. The main advantage of ADSL, however, is
that it provides substantially more bandwidth than basic rate ISDN. Compared with the 128 kb/s
maximum bandwidth of a basic rate ISDN line, ADSL offers up to 1.5 Mb/s downstream plus POTS in
current versions--and up to 8 Mb/s downstream plus POTS in versions currently under trial. And unlike
ISDN, ADSL customers will not lose service in a power outage, says Jeff Waldhuter, executive director
of research and development for Nynex.
On the other hand, ISDN allows customers to contact multiple sites and users, while ADSL is only being
talked about as a dedicated connection to one site such as the Internet, he says.
"ADSL will be rolled out on an application-by-application basis," Waldhuter says.
TeleChoice's Taylor believes ADSL will not be plagued by as many problems as ISDN has experienced.
"ISDN is a protocol, and ADSL is just a physical layer," he says.
ADSL will not have the same protocol issues that ISDN did, especially when the latter was initially
deployed, Taylor says, adding that ADSL will be easier to order and users will not have to worry about
issues such as SPIDs or signaling protocols.
"ADSL and cable modem vendors will learn from the mistakes of ISDN--marketing the technology
instead of the service [for example]," Taylor says.
With easier ordering and simplified service support, ISDN is in a position to change its image. But
ISDN's proponents are likely to have an uphill battle getting it onto the best-dressed list this year.
"ISDN's bad reputation will linger, but focused marketing will dispel some of that," says Taylor. "It will
take some intelligent spin doctors to reverse conventional wisdom."
Denise Pappalardo was East Coast Bureau Chief at the time this story was written.
Spelling it out
EZ-ISDN is a proposal that was approved by the North American ISDN Users Forum with the goal of
simplifying ISDN from an equipment standpoint. For example, when ordering ISDN service, customers
who purchase a compliant device can tell their service provider they want EZ-ISDN 1A so that the
service provider will know how to provision the line.
EZ-ISDN 1 provides an alternate circuit-switched voice/data calling feature for B channels on a basic
rate ISDN connection. Voice features include additional call offering, flexible calling, call forwarding
variable, calling party number identification and redirecting number delivery. Data features such as calling
party number identification and redirecting number delivery are also included.
The EZ-ISDN 1A package includes all the features and capabilities of EZ-ISDN 1 as well as some
additional voice features, including a visual message waiting indicator, call forwarding/busy and call
forwarding/don't answer.
--DP
Where to find information about ISDN on the Internet
* The North American ISDN Users Forum isdn.ncsl.nist.gov
* Dan Kegel's ISDN Home Page alumni.caltech.edu
* California ISDN Users Group ciug.org
Good luck. |
