Collaborative Conferencing: The Role
Of POTS And Voice Over IP
BY DAVID C. STUART
Collaborative conferencing is not something new -- we do it every time we interact with
others via a phone call or in a meeting. What is new is the ability to remotely conference
with high-quality audio and visuals, simulating the in-person experience, while overcoming
the constraints of time and space. By combining the strengths of telephone networks with
the strengths of the Internet (and related Web technologies), companies can create
easy-to-use, robust, reliable, and cost-effective collaborative conferencing systems that
benefit by reducing costs and increasing productivity.
Integrated technologies have now made it possible to combine the data-richness of the
Internet and intranets with the quality and ubiquity of the existing phone system to
create a complete voice and data conferencing solution. Using inexpensive, PC-based
products, a voice and data conference server can integrate POTS audio conferencing with
IP-based data conferencing while reducing teleconferencing service costs. Users can manage
these conferences on their own without resorting to a teleconferencing service provider,
using simple Web-based interfaces. By allowing users to control communications,
organizations can reduce costs and boost employee and group productivity, particularly
within highly distributed work environments.
So, what's the upshot of such a teleconferencing system? Streamlined, collaborative
conferencing that meets today's business needs will increase productivity by improving
communication in a distributed work environment. And it is available today.
THE NEW BUSINESS LANDSCAPE
Companies are deploying a new generation of network-savvy computing solutions that
leverage widespread communications services such as the Internet to connect people with
information. The familiar corporate models dictating how workers interact with each other
and with the information assets of the corporation are becoming outdated. Mobile
computing, virtual work forces, and an acceleration of business processes and product life
cycles characterize the new business landscape.
Meanwhile, innovative companies are beginning to blend the activities of their
customers, suppliers, and partners into a cohesive set of online business processes.
Intranets and extranets are the new locus of activity, as organizations rush to bring
their cohorts online and the communications between computers become as common as the
connections among telephones.
TELECONFERENCING -- TRIED AND TRUE
These new business realities are increasing the need for easy-to-manage, robust
teleconferencing services. As telecommuting, mobile work forces, and portable computing
devices become more popular, companies are challenged to maintain efficient workgroups
that can interact and collaborate in an easy, efficient manner. Workers need new types of
conferencing and communications services to do their jobs, regardless of location.
As corporations and their work forces become more distributed, projects require more
and more collaboration between work sites. Increased outsourcing and telecommuting also
increase the need for collaborative conferencing and the number of locations taking part
in a typical conference.
REQUIREMENTS
The new business requirements for collaborative conferencing include the following:
Ad Hoc Scheduling
Businesses have reduced their time-to-market - many say they are "working in Internet
time." This change requires support for spontaneous conferencing. However,
traditional teleconferences require advance planning, including separate calls to the
telephone service vendor and often each participant.
Self Management
In the past, support personnel scheduled teleconferences and connected participants to the
conference. Today, the reduction of support staff at most organizations requires that
conferences be easy for any participant to set up and manage.
Integrated Data Conferencing
Conference participants often need to share materials stored on their computers or on the
corporate network. Collaborative conferencing solutions need to support conferences with
both shared data and audio conferencing.
Robust Conference Control
Traditional teleconferencing does not provide ways to interactively add, remove, and mute
participants or allow offline chat or polling. Businesses need such capabilities for
effective meeting management.
Reduced Cost
Costs for traditional teleconferencing are high. Forty to fifty cents per minute per line
is typical, and there is an additional setup charge in many cases. These fees add up
quickly for a company that uses teleconferencing extensively. To reduce capital outlays,
solutions need to leverage existing phone and network infrastructure.
THE ROLE OF PSTN
The public switched telephone network (PSTN) has a number of strengths that make it an
attractive tool for collaborative conferencing.
Ubiquity: Everyone has access to the PSTN. Wireless phones provide
access from almost anywhere.
Familiarity: Everyone knows how to use a telephone. A technology that
required the use of PC-connected microphones would be unfamiliar to many people.
Quality and Reliability: The quality of PSTN telephone connections is
high, especially in comparison to some Internet telephony solutions. Also, we have come to
expect the phone system to simply "work."
Functionality: Features such as call forwarding and voice messaging
are available over PSTN without the purchase of additional equipment.
However, when it comes to collaborative conferencing, PSTN alone has several weaknesses
that limit the effectiveness and efficiency of collaboration.
Lack of Data-Richness: Collaboration requires both discussion and the
sharing of information. The PSTN supports only the discussion segment of the process.
Expensive: Companies typically pay $24 per hour per participant for
third party-based teleconferencing. These costs are high compared to the cost of
point-to-point calls, and much higher than the cost of time on leased lines used for
typical private data networks. Customer premises-based conferencing equipment can reduce
these costs substantially.
Cumbersome Setup: The setup process for a PSTN-based teleconference
involves a number of coordination steps. If this process were simple and fast,
communication and employee productivity would improve.
THE ROLE OF VOICE-OVER-IP
While IP has historically been used for data transfer, and indeed is optimized for data
traffic, there are several ways of transmitting voice over an IP network. Corporations are
very interested in cutting their telephone bills by using their IP networks for voice
traffic.
Internet Telephony
Much attention has been given to Internet telephony -- using a microphone and speakers
connected to a computer to converse over the Internet without paying long-distance
charges. But, those who have used Internet telephony admit that the audio quality is poor.
Note that the problems with voice-over-the-Internet are problems with two-way
conversations. One-way voice transmissions -- voice messaging and broadcast audio -- can be
sent over the Internet quite well. Streaming technology allows one to play audio directly
from Web sites. Faxes can also be sent over the Internet effectively, because fax machines
continue to work with acknowledgment delays long enough to preclude human conversation.
What Will It Take To Make Internet Telephony Work?
A number of methods have been proposed for solving the jitter and latency problems
commonly experienced with Internet telephony and other real-time Internet applications.
Assigning a higher priority to voice connections: IP - the network protocol used by the
Internet, corporate intranets, and many local-area networks (LANs) - was not designed to
provide a way to give voice traffic higher priority than other types of traffic, such as
e-mail. As a result, Internet congestion causes slow voice transmissions, which causes
poor audio quality.
Several methods have been proposed to solve this problem. The leading contender is the
Resource ReSerVation Protocol (RSVP), which provides a way to reserve IP bandwidth and
give delay-sensitive traffic, such as voice and video, priority over data traffic.
However, RSVP requires that every router along the data path provide special support
for RSVP. Since RSVP is relatively new, most routers on the Internet need to be upgraded
or replaced to accommodate it. Considering that there are over one million registered
domains on the Internet, the number of routers that would need to be upgraded is very
large. This represents a huge expense, so this problem is not likely to be solved soon.
Increasing bandwidth: Another method for improving audio quality would
be to increase the bandwidth of the Internet to prevent congestion. Unfortunately,
Internet traffic is growing as fast as or faster than the capacity to handle it. At this
stage of Internet expansion, service providers are struggling to provide enough bandwidth
for e-mail and Web traffic. The excess bandwidth required to improve Internet audio
quality is presently beyond their reach.
Improve compression algorithms: Much work has gone on in this area
with recent progress in audio algorithms (G.723) that reduce network bandwidth demands for
transmission of human voice. Audio codec algorithms will continue to improve, paving the
way for higher-quality Internet telephony transmission.
VOICE OVER INTRANETS
Over an intranet, the same tools used for Internet telephony can provide acceptable audio
quality and dependability. This is because an organization can ensure that its own network
is engineered to meet the latency requirements of voice traffic. They may also be able to
implement RSVP or a similar quality of service protocol within the private network.
However, substantial investments in new protocol support (such as H.323) across network
infrastructures (routers, hubs, gateways, and servers) and additional equipment -
microphones, speakers, and software - are required for every computer connected to the
system. And, features that we have come to expect from the PSTN or PBX-based systems, such
as call forwarding and voice mail, are not commonly provided with Internet telephony
tools.
VIRTUAL PRIVATE NETWORKS (VPNs)
By connecting the corporate IP network to corporate PBXs and phone systems, the existing
telephone equipment on employee desks can be used to send voice traffic over an IP
network.
This allows corporate IP-based intranets and wide-area networks to effectively transmit
voice traffic, reducing long-distance charges between distributed facilities. These
networks can be engineered and managed to provide the bandwidth and traffic prioritization
required for quality two-way voice communication.
In most implementations, corporate PBXs are connected to the LAN by gateway devices.
Employees dial access codes on a regular telephone to place a call using the IP network.
Other than using access codes, the transmission mechanism is transparent to the
participants in the call.
COMBINING THE STRENGTHS OF POTS AND IP
Existing telephone networks provide excellent audio quality, but lack the multimedia
capabilities necessary for collaborative conferencing. In contrast, the Internet and IP
weren't designed for voice traffic, but have the potential to add data-richness to
traditional audio conferences. Private IP networks can be used to reduce long-distance
charges between distributed sites.
By using the strengths of telephone networks in combination with the strengths of the
Internet and other IP networks, companies can realize the best of both worlds.
A conferencing server can be connected to the PSTN and corporate PBXs by T1 voice
lines. The server is also connected to the corporate data network.
This conferencing server should control multiple point-to-point telephone connections
(either from PBXs or PSTN) to provide high-quality teleconferencing at a reduced cost. In
addition, it should allow conferences to be managed interactively through a Web-based
interface. And, it should support the T.120 standard for data collaboration so that
applications such as Microsoft NetMeeting can be integrated with the conferencing system.
Using the public switched telephone network (PSTN) for voice transmission provides
excellent audio quality. In addition, it leverages the investment companies have already
made in PBXs and telephone networks. Telephones aren't going away anytime soon, and people
are comfortable using them.
Using such a conferencing server allows teleconference participants to establish
low-cost point-to-point connections via a telephone number assigned to the conference
server. The conference server then acts as a bridge to combine these calls into a
conference call. This allows companies to avoid setup charges and premiums on
teleconference calls.
- Using Web-based tools to schedule and manage collaborative conferences provides numerous
benefits:
- No additional software or hardware is required on participant desktops.
- An existing Web browser can be used to schedule, join, and manage conferences from
anywhere.
- Individual users can easily schedule, join, and manage their own conferences.
- No attendant is required, which lowers the costs and keeps conferences private.
- Changes and improvements to the management interface do not require new client code to
be distributed.
- The system is managed centrally from the server.
- Supporting T.120-compliant applications such as NetMeeting adds the ability to use a
shared whiteboard and to share files or applications within the collaborative conference.
- Users can edit documents, update spreadsheets, and attend presentations in common with
others from their desktop.
Since the server manages the conference, both telephone conferencing and T.120-based
data conferencing are set up and controlled through an integrated Web-based interface.
Furthermore, using the server to host the data conference shifts the management burden to
a more stable and robust NT platform from the typical over-taxed desktop PC.
David C. Stuart is vice president of marketing at OutReach Technologies, a division
of Communication Systems Technology, Inc. (CSTI). The division was established in 1995 to
capitalize on CSTI's success as a developer of wide-area audio conferencing, audio/data
switching, and remote radio control systems for the federal marketplace. OutReach
Technologies applies these technologies to meet the critical communications issues facing
corporations and institutions. For more information, visit the company's Web site at www.outreachtech.com.
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