March 2000
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Just
Something About Standards BYCHRIS DONNER |
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Open and standards-based these words are
the hits, the stars, the Ben Stillers and Cameron Diazes of modern-day
communications. And yet, much remains to be accomplished in terms of true
interoperability, even when standards are involved. Consider H.323
vendors have to implement their own versions of the standard to handle
advanced functions, and suddenly the products dont interoperate any
longer. Or if they do, only basic features carry over.
What really matters in standards development is implementation, with
Windows being a perfect case in point. Almost no one I have spoken to in
the communications community thinks that Windows is the absolute best OS
for their purposes it has its plusses and minuses like anything else.
But it has become a de facto standard through massive implementation.
There are challengers, of course, but the point remains: vendors and
developers must deploy standards quickly and on a fairly large scale if
they want them to be embraced. Deployment, it would seem, is more
important than functionality.
In talking with developers, I have heard generally two opposing views
on the proliferation of standards:
- Standards compliance is absolutely imperative when developing new
products and services. Carriers, enterprise users, ASPs, etc. all
demand that products interoperate, and standards allow this without
requiring custom coding.
- Standards are a good idea on paper, but the technology is changing
too quickly for anyone to really lock it down. Innovation and new
services mean pushing the technology to its limits. Specific standards
will only be accepted when the majority of industry players feel that
there is more to be gained from interoperability in a certain area
than there is to be gained from pushing the limits and beating the
competition.
Often it seems that effective standards are not put in place until the
standard addresses issues at such a low level that no one really wants to
compete there any longer. It is implemented with little argument, and
vendors working in that space either branch out or decide to (gasp!)
compete on price alone.
This doesnt exactly demonstrate viable standards in a competitive
market. So, is such a thing a real possibility, or just wishful thinking?
This month some key players in the communications industry discuss the
importance and place of standards in the communications market. I am also
very interested in any reader comments on the practicality of standards,
especially from developers and integrators working in the field. Comments
are welcome at lguevin@tmcnet.com.
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Enabling News
Digi And Red Hat Focus On Linux-Based Comm Servers
Digi International has announced an agreement with Red Hat to join
in marketing programs that will enable distributors, resellers, and
integrators to offer Linux-based communications servers designed
specifically for the small to medium-sized business market. Jones Business
Systems, Inc. (JBSi) will be one of the first distributors to participate
in the program, offering resellers and integrators a variety of bundles
which can then be customized to meet specific customer requirements.
No. 515, www.comsolmag.com/freeinfo
Crystal Card Turns Computer Into Phone Console
Crystals Audio Operator Console (AOC) voice board provides all
the functions needed to use desktop computers as telephony operator
consoles in a multi-line facility such as a call center. The AOC card
provides dual four-wire analog transmit and receive lines, DTMF detection
and transmission, and dual line inputs and outputs with crossbar
switching. The AOC card is compatible with the ISA bus, has SoundBlaster
mono audio, and has APIs and software drivers for most OSs.
No. 516, www.comsolmag.com/freeinfo
Trenton SBC Offers Choice Of Processors
Trenton has added Intel Pentium III FC-PGA processors to Trentons
CBI product line. By expanding the CBI SBX line to include a choice of
either the Pentium III or Celeron processors, Trenton offers customers an
SBC with a choice of flexible performance platforms and long-life cycle
support, says Bill Bowling, VP of sales for Trenton. The Pentium III
CBI is available now in seven performance models up to 800 MHz with prices
starting at $2003.
No. 517, www.comsolmag.com/freeinfo
MiTAC Intros 2U Rackmount Chassis
MiTAC has introduced the MCH-224-ATX and MCH-218 series of 2U, 19-inch
rackmount chassis, designed to provide high computing power in limited
space for the ISP and CTI industries. The MCH-2240-ATX accommodates eight
disk drives, while the MCH-218 has space for six ISA/PICMG cards and three
disk drives. MiTACs MiXpress 2U servers are also available based on
these two chassis models.
No. 518, www.comsolmag.com/freeinfo
Silicon Labs Intros ProSLIC CMOS Analog Interface
Silicon Laboratories announced the Si3210 ProSLIC CMOS analog
telephone interface, which integrates the subscriber line interface
circuit (SLIC), codec, and DC-to-DC converter controller into a single
CMOS integrated circuit. The ProSLIC is programmable to meet global
telephony standards, allowing implementation in various short-loop
applications including cable telephony, WLL, PBX, VoIP, and ISDN terminal
adapters.
No. 519, www.comsolmag.com/freeinfo
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Industry
Comments
Capabilities
that every vendor offers, where the mode of implementation adds no
value-add, become appropriate areas for standards adoption. In those
scenarios, Dialogic will endorse standards to enable our customers to
get to market quicker.
Bill Spain, Product
Marketing Manager, Dialogic.
I think its fair to
say that having some baseline standards is absolutely necessary for the
existence of technology-based industries. Where would the electrical
appliances business be if every manufacturer were free to design their
own power plug? At the API level, standards are a newer concept.
Standard APIs have tremendous potential value in giving developers
hardware independence. On the other hand, we believe there will always
be room for vendor-specific APIs that give developers access to new
hardware capabilities, and that address application spaces for which the
standard has not necessarily been optimized.
Josh
Adelson, Marketing Developing Manager, Brooktrout Technology.
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Q:
Even in the vendor community, there is
strong disagreement on standards. To some extent, it would seem,
standards disagreements are religious wars and can be difficult or
impossible to resolve. How might a developer find the truth behind
these disagreements? Should developers determine their potential
customers first and then decide what to support based on what their
customers require?
A: The
general consensus among the respondents here was that adoption equals
importance and suggests that the standard is meeting a market need. The
standard must fit the needs of the customer rather than offer standards
compliance merely for the sake of complying.
Force Computers
believes in addressing the specific needs of our customers, and were
willing to design to fit where there is need and justification. We
also believe that standards-based products are the foundation of a
design-to-fit business model.
Dick Somes, Technical Director for
Standards and Industry Relations, Force Computers; VP and Technical
Officer, PICMG.
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For our
customers the standards are not icing, but rather the flour and eggs
with which to prepare the batter. At RADVision, we gather all the best
ingredients and mix the batter for them into an instant mix so
that they can then use the mix to adapt to their target markets
favorite recipe.
Danny Levin, VP Engineering in
North America, RADVision.
Standards are
key to success in the VoIP industry. The industry got off on a false
start with the ITU H.323 standard. Its a complex and slow call
processing standard that does not scale well. The industry learned its
lessons in field trials and commercial deployments and is now shifting
towards SIP and MGCP. These two standards empower all vendors to easily
interwork, and they provide the building blocks necessary for a new
generation of voice technology.
Larry Greensten, Director of Product
Development, Nuera; VP Technology, Frame Relay Forum
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Industry
Question -- Developer Decisions
Q: How does a
developer decide what standards to support and what can be safely ignored
or supported in a later release? How much does the pursuit of compliance
affect a developers time-to-market, and are there any tips you can
offer that would help a developer determine when enough is enough?
A: Developers need to balance standards against innovation and
differentiation. Ultimately, end users are looking for solutions that
either reduce their operating costs or increase their competitiveness.
Vendors should adopt standards when the areas addressed by the standards
represent generic functionality that offer no value-add based on the
method of their implementation.
Bill Spain, Product Marketing Manager, Dialogic.
Its pointless to argue over whether standards are good or bad for
the developer community. In the end, its the market requirements or
anticipated market requirements for a new product that determine which
standards are relevant. Think first of what helps your own customers and
prospects.
Brough Turner, Sr. VP and CTO, Natural MicroSystems.
A good standard enables non-standard features to operate in a standard
way. It implies common basic functionality among all vendors with extra
features among specific vendors. When there is more than one standard for
a specific task the best method is to use layers and abstraction as much
as possible. The application (upper layer) should be standard agnostic. If
the software is designed well (layers and abstraction) most of the
software can be preserved for all standards.
Danny Levin, VP Engineering in North America, RADVision.
The value of standards is difficult to assess as an abstraction. It can
only be done relative to a particular perspective to accomplish a
particular goal. Some standards, such as TCP/IP, cannot be ignored. Others
have a different value depending on the company. For example, the purpose
of M.100 is to reduce the costs of building integrated-media system
resources. Multi-vendor media integration has high value to a small
company. But the industrys market-share leaders view it as a threat to
their ability to compete through capital formation, preferring to leave
common-platform media integration to differential competitive
advantage.
Mike Coffee, President, Commetrex Corporation.
Using a good layer of abstraction allows a design to be changed more
quickly. It also allows multiple standards to be incorporated. Standards
are often more determined by marketplace factors. Often, technically
better standards dont win, but those which are backed by better
marketing efforts or deeper pockets. The first step to success for an
engineer with a good idea is to either become a competent marketer or team
up with one who has a proven track record.
David Medin, Director of
Technology, Crystal Group.
Compliance with industry standards for the purpose of interoperability
has repeatedly been shown to benefit consumers, suppliers, and the growth
of the industry in general. Whether discussing fax machines, e-mail .JPG
attachments, roaming around the globe with a GSM cell-phone, or just Web
browsing, it is clear that compliance with standards benefits us all.
Larry Greenstein, Director of Product Development, Nuera; VP
Technology, Frame Relay Forum.
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SIP:
The Protocol That Roars (Over IP)
As the industry accelerates towards delivering converged services, two
standards have emerged for IP telephony signaling: H.323, developed by the
ITU-T, and SIP from the IETF. While H.323 has a role to play, SIP is
gathering momentum as the protocol to support the global communications
network.
H.323: The Current Standard
H.323 specifies an architecture for handling multimedia sessions over
packet. H.323 also handles encoding, decoding, and packetizing audio.
Initially intended for ISDN, H.323 moved to the LAN and has been evolving
over the last eight years.
As a result of this re-development, H.323 has now become somewhat
complex. Backward compatibility requirements make it cumbersome, and it is
coded in abstract bit patterns (ASN), which makes it complicated to
develop, debug, and add features to. It is also widely recognized that
H.323 has certain interoperability challenges. Because of its centralized
control design, H.323 does not integrate well with other Internet
technologies, such as IP security.
This said, H.323 commands a strong position in the industry. It is an
integral part of several leading applications and is also being used in
trials for PSTN bypass. As it was the first standard to emerge in this
space, H.323 is at the heart of most first-round VoIP products currently
on the market.
SIP: The Contender
SIP is an inherently Internet friendly protocol that easily integrates
the Web and voice services. It supports all CLASS features and allows an
array of new services that couple standard telephony with information
access and personalization.
SIPs most significant advantage over H.323 is its design. SIP
follows the principles of simplicity and distributed intelligence, much
like protocols such as SMTP and HTTP, which are clearly capable of serving
the world. With SIP, developers can design and implement new voice
services as easily as they would a Web page, and the expectation is that
SIP will have the same profound effect on the telephone as HTTP has had on
the Web.
SIP will make voice just another IP service. In other words, advances
in other Internet protocols help SIP, since SIP leverages them for an
end-to-end IP telephony service. SIP also has the advantage of being text
based, which makes it simpler to implement, interoperate with, and debug.
Determining The Future
Perhaps the most exciting aspect of SIP is that it will allow the
introduction of new services that combine standard telephony with
information access and personalization to create smart client devices.
Consider PDAs. They have enough power to act as an interface for an
intelligent phone. In addition, user data can be utilized to adapt the
network to the individual. For example, by synchronizing information on
the PDA to an SIP Ethernet-phone, the owner of the PDA can register
with the phone, allowing the phone to adopt the PDA owners preferences,
such as speed dialing, voice mail short-cuts, and advanced features such
as sophisticated call forwarding for true number portability.
In another example, the address book and appointment book data can be
synchronized with the SIP phone to program advanced call screening. The
user only accepts calls from callers in the address book, forwarding
others to a third party or voice mail.
It is these new services that will deliver on the true promise of IP
telephony and make it a compelling business application. SIP will provide
the means to deliver such services quickly and easily.
Each Has Its Role
For the time being, H.323 and SIP will co-exist, and mechanisms for
basic call set-up and tear down between them will be developed. In the
near future, however, SIP will emerge as the dominant signaling protocol
for the Internet. It will become the de facto protocol between smart
clients and between soft switches and other network elements.
Ikhlaq Sidhu is VP of Internet Communications at 3Com. For more
information, visit www.3com.com.
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Standards
For Cable Telephony
The release of the PacketCable 1.0 spec by CableLabs promises to
unleash not only basic IP telephony over cable, but exciting new features
as well. Here, we will examine the PacketCable 1.0 architecture, uncover
its most appealing features, and reveal how it can fit into existing
networks.
Its About Trust
PacketCable 1.0 is built upon the Network Call Signaling (NCS) model.
NCS assumes that the Multimedia Terminal Adapters (MTAs) in peoples
homes will be simple devices. Users plug phones into these MTAs, which
perform actions such as detecting when a phone is off hook or when a digit
is pressed. MTAs cannot generate dial tone or place calls without help
from a third-party server.
Consumers trust their phones because they never crash. By limiting the
functionality within MTAs and thereby improving their reliability, NCS
proponents are certain these devices should garner similar confidence.
With My Brains And Your Brawn
The server that provides the intelligence is known as Call Management
Server (CMS). CMSs use MGCP to inform an MTA when to generate dial tone,
busy signals, and virtually all other telephony functions. The CMS and MTA
exchange event information: when the MTA detects an event, it alerts the
CMS, which examines the event and instructs the MTA how to react. For
instance, if you take the phone off hook, the MTA signals the CMS. Then,
the CMS determines the appropriate dial tone for your home and instructs
the MTA to play that tone.
What distinguishes the NCS architecture from competing protocols such
as H.323 is the CMSs ability to use MGCP events to transform an MTA.
For instance, a minor software tweak on the CMS could let the MTA have
conventional dial tone during business hours and stutter tone during
off-hours without code changes on the MTA. An H.323 device would require a
software patch to provide this same functionality.
Another benefit is the ease of feature creation. When an MTA
initializes, it requests a digit map from the CMS. The digit map tells it
which sequence of key presses should generate an event. If these
combinations are dialed, the MTA fires an event to the CMS and the CMS
takes the appropriate action.
To add a new feature, simply update the digit map. The CMS then
forwards the updated digit map to the correct MTAs. For example, to
retrieve your e-mail and convert it to voice mail, you would first inform
the CMS of the appropriate key presses. When the MTA detects these key
presses, it alerts the CMS, and the CMS invokes the service to retrieve
the e-mail and convert the text to speech. Finally, the CMS will stream
the text-to-speech to the MTA. Thus, features can be added without
modifying the MTA.
Working With Existing Networks
Although NCS lets you place calls and define features, it does not address
issues such as billing, provisioning, and accessing legacy networks such
as the PSTN. The PacketCable 1.0 spec defines how components such as
billing and provisioning interact with NCS elements.
Besides accessing legacy devices, NCS solutions will have to
communicate with H.323 and SIP. Although this isnt defined by
PacketCable 1.0, SIP is gaining momentum as the preferred mechanism to
bridge NCS networks to other architectures. But no matter what protocol is
selected, the CMS alone is responsible for translating events and
commands. MTAs remain blissfully ignorant.
PacketCable 1.0 is a significant advance in cable telephony. Its use of
the NCS call model should provide stable devices that consumers can trust,
while enabling a tremendous number of new features.
Linden deCarmo is Sr. Software Engineer at NetSpeak, and the author
of Core Java Media Framework. He can be reached for comment at [email protected]
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Industry
Question -- Proliferation Of Standards Bodies
Q: Another
area of confusion when discussing standards is the increasing
proliferation of standards bodies, which places a heavy burden on the
garage-based developer who doesnt have the funding to send a
representative to track all the relevant groups. What advice could you
offer a developer who is concerned with standards but who is also limited
by resources?
A: It doesnt matter where a standard comes from. What counts
is the standards level of adoption. Its a corollary to Metcalfes
Law of Networking that the value of a standard increases as the square of
the number of people using it. I prefer standards that are not controlled
by one company, but there will always be single-company architectural
standards and vendors who profit from them. Theres no need to encourage
such efforts, but if they succeed, then adoption is a no-brainer you
go along or you lose out on the largest part of the market. A garage-based
developer should be able to track [relevant standards] from news reports,
e-mail reflectors, Web sites, and discussion with customers or prospects.
Brough
Turner, Sr. VP and CTO, Natural MicroSystems.
The apparent proliferation of standards bodies is largely a result of a
need to specialize. But most of the proliferation is really division of
labor. For example, both the PCI/ISA and CompactPCI architectures have
been further enhanced for telecom applications by TDM busses, H.100 for
PCI/ISA (and commodity) systems, and H.110 for CompactPCI. So a CompactPCI
computer-telephony platform draws on hardware standards from at least five
different standards bodies or industry consortia, each with its own area
of expertise.
Dick Somes, Technical Director for Standards and Industry
Relations, Force Computers; VP and Technical Officer, PICMG.
Garage-based developers are not the only ones limited by their
resources. Even industry giants with capital are missing one critical
factor: time to market. This is where a third-party vendor comes into
play. Using a protocol software frees up the developers time and money
to concentrate on application development.
Danny Levin, VP Engineering in North America, RADVision.
Get on the Web! Its the great leveler. The best example is the IETF,
which has a completely open standardization process. Competition among standards
bodies and industry consortia, even though it creates some confusion, is
not necessarily bad. The arrogance of monopoly power in the
standards-setting process is bad.
Mike Coffee, President, Commetrex
Corporation.
My feeling is that the marketplace will listen to those [standards
bodies] that make their information and development process available
through the Internet, where those that are used to charging exorbitant
fees and have costly meetings will have decreased impact.
David Medin, Director of Technology, Crystal Group.
It is important to note that if proprietary implementations by large
organizations were the norm, then the garage-based developer would have
little chance to participate in a growing market segment.
Larry Greensten, Director of Product Development, Nuera; VP
Technology, Frame Relay Forum.
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