Article about web conferencing by David Geer

Page 1

Computer

I N D U S T R Y T R E N D S

Published by the IEEE Computer Society

eb conferencing has be-

come an increasingly de-

sirable option for busi-

nesses that don’t want

to spend the time and

money it takes to fly employees

around the world for meetings that

don’t require face-to-face contact.

“The real key is reducing the time it

takes to make a decision,” explained

Gerry Kaufhold, principal analyst with

In-Stat/MDR, a market research firm.

As Figure 1 shows, global revenue

from Web conferencing services in-

creased 70 percent—from $450 mil-

lion to $765 million—between 2002

and 2004 and will reach $1.5 billion

by 2007, according to Kaufhold.

Traditionally, Web conferencing has

been offered as a service hosted by a

third-party provider. However, three

recent developments are changing the

face of the technology.

Manufacturers such as eDial, Juni-

per Networks, Nortel Networks, and

Polycom have begun selling Web con-

ferencing server-based software sys-

tems that companies can run them-

selves on their internal network, dedi-

cated servers, or network appliances.

This approach enhances security, con-

trol over collaborative operations, and

integration with existing communica-

tions infrastructures.

Vendors such as Cisco Systems, with

its MeetingPlace application, are now

combining service- and server-based

conferencing—with some functions

handled by in-house servers and oth-

ers by service providers—into hybrid

approaches that try to provide the best

of both worlds.

Meanwhile, the Internet Engineering

Task Force (IETF) is working on Web

conferencing protocols that promise

greater flexibility, interoperability, and

accessibility.

SERVICE-BASED WEB

CONFERENCING

Web conferencing enables audio,

video, document, and image exchanges

among multiple participants over the

Internet via technologies such as Web-

cams; Internet telephony; desktop shar-

ing, which lets users remotely view and

control one another’s desktops; white-

boarding; text messaging; and chat.

As with instant messaging (IM),

with Web conferencing applications,

users can determine who is online and

available for a meeting via presence

technologies.

Web conferencing provides secu-

rity—via encryption, digital certificates,

and authentication—using Secure

Sockets Layer technology; proprietary

SSL-based approaches; or transport-

layer security, a successor to SSL.

Typically, providers such as Meeting-

Bridge and WebEx have offered Web

conferencing as a service. With these

services, users pay providers for each

conference and then call up meetings

via a Web browser. The providers sup-

ply the bandwidth, interface, and tools

such as those for coordinating sched-

ules, sending participation instructions,

and checking browser settings for com-

patibility. They also offer technical sup-

port to participants.

Advantages

Participating in a service-based con-

ference costs considerably less than

buying a Web conferencing server.

Third-party services also eliminate the

need for companies to have their own

personnel to run, maintain, and fix the

conferencing infrastructure.

These factors are ideal for companies

that want to test the technology before

buying their own server or that have

small budgets and little or no IT staff.

Because the services are easily scal-

able, users can buy as much confer-

encing as they need at any time,

explained Andy Nilssen, senior analyst

with Wainhouse Research, a market

analysis firm.

In addition, services, with their

clearly defined fees, are good for busi-

nesses that pass all or some of the con-

ferencing costs on to clients or partners.

Disadvantages

In some cases, frequent users can

spend more paying for conferences one

at a time than buying their own equip-

ment. In addition, Web conferencing

services pose a potential security risk

because they bypass the normal secu-

rity policies that a company’s IT per-

sonnel establish.

Web conferencing services bypass

policies because they require applica-

tion sharing between participants,

which enables system access from the

outside. Also, conferencing-system

bugs can create security vulnerabilities.

Developments

Advance Web

Conferencing

David Geer

Published by the IEEE Computer Society

Page 2

February 2005

integrate their Web conferencing

servers with the rest of their commu-

nications infrastructure, which offers

multiple benefits.

Hackers can exploit these problems

to infect systems with malicious soft-

ware, intercept documents and other

files passed during sessions, or gain

entry to conference participants’ sys-

tems and files.

SERVER-BASED WEB

CONFERENCING

Avaya’s Web Conferencing Server,

Juniper’s Secure Meeting, and Poly-

com’s WebOffice, shown in Figure 2,

are examples of server-based Web con-

ferencing systems.

In server-based approaches, compa-

nies operate their own Web conferenc-

ing systems. Their conferencing servers

create and maintain a tightly coupled,

real-time communications infrastruc-

ture under their control.

Tightly coupled systems have a cen-

tral point of control and authorization

to enforce conference rules about mat-

ters such as who has access to applica-

tions, explained Alan Johnston, cochair

of the IETF’s Centralized Conferencing

Working Group and an MCI distin-

guished technical member.

Client software communicates with

the conferencing server in various ways.

For example, said

Bernadette Golas,

Avaya’s director of product marketing

for conferencing solutions,

“Users con-

nect to Avaya Web Conferencing

Servers through a Java client that they

download through their Web browser.”

As with service-based systems, servers

automatically check each potential con-

ference participant’s availability, iden-

tify those who can take part, and record

the conference for later use by those

who can’t attend.

The servers enable a meeting using

videoconferencing, Internet telephony,

IM, document collaboration, and

other communications tools available

to participants via their browser-based

interface.

Advantages

The server-based approach lets com-

panies, not service providers, decide

whether and when to upgrade confer-

encing systems. Companies also can

For example, users could work with

their company’s single-sign-on capa-

bilities to log in once for multiple net-

work activities, including Web con-

Source: Polycom

Presenter/

conference

leader

Enterprise

WebOffice

server

Participant

Router

LAN, WAN,

or Internet

Shared

documents

Figure 1. Revenue from Web conferencing services has increased throughout the world,

particularly in Asia, and will continue doing so, according to In-Stat/MDR.

2002

2003

2004

2005

2006

2007

100

200

300

400

500

600

700

Millions of US dollars

North America

Europe

Asia

Rest of the world

Source: In-Stat/MDR

Figure 2. With Polycom’s WebOffice server-based conferencing system, a company

running its own equipment can start a session on an internal LAN or WAN with participants

from inside the organization or over the Internet with participants from outside the

enterprise. All participants work over Web browsers. The presenter who is leading the

conference is sharing two pages of a document with other participants.

Page 3

Computer

For example, along with

providing

service-based conferencing, Raindance

Communications will manage servers

located in companies’ offices, according

Wainhouse’s Nilssen

Some equipment vendors are provid-

ing services and servers. For example,

Cisco can manage some of a company’s

conferencing-related servers by moving

them outside security applications,

including the firewall. The customer

manages the servers that are behind its

security applications.

With this approach, people within a

company stay on the secure corporate

network, and people outside the com-

pany, who present more of a security

risk, don’t get inside the security appli-

cations, explained Troy Trenchard,

Cisco’s director of product manage-

ment for rich-media communications.

Companies with their own confer-

encing servers can benefit from work-

ing with service providers, who

frequently can better tie in participants

outside the enterprise and also can

offer enhanced reliability and redun-

dancy for some conferencing services.

Along with their advantages, hybrid

services can entail both server-based

Web conferencing’s initial deployment

costs and service-based conferencing’s

ongoing service charges.

STANDARDS

Traditionally, parties to a Web con-

ference have communicated with one

another via proprietary application

program interfaces. To conduct Web

conferences, users on different plat-

forms that don’t share APIs must spend

considerable time and money making

their systems interact.

Providing more interoperability,

which will make conferencing avail-

able to larger groups of people regard-

less of platform, will require standards.

ferencing. Integration with a company’s

Web directory lets users easily find and

work with in-house participants.

Participants can use existing net-

work tools, and businesses can avoid

running and managing multiple infra-

structures. Integrating Web confer-

encing into familiar infrastructures

also shortens the IT personnel’s learn-

ing curve.

Server-based Web conferencing is

more secure, in part because compa-

nies control the entire system. In addi-

tion, operations based on a company’s

single system result in fewer potential

vulnerabilities than operations involv-

ing both service providers’ and users’

systems.

With server-based Web conferenc-

ing, companies are aware of security

breaches in their own systems more

quickly than if third-party providers

operate the conferencing application.

Disadvantages

Companies that run their own con-

ferencing servers must use their own

bandwidth for group meetings, which

can be a problem for small businesses.

Server-based Web conferencing en-

tails software licensing fees and large

equipment costs, including servers; load

balancers, which determine the switches

to which the system should connect new

conference participants to balance the

overall switch load; multipoint control

units to manage multiuser conferences;

and audio bridges for those joining a

session only by phone.

Also, staff members must learn how

to administer and manage server-based

systems.

HYBRID SYSTEMS

Some companies are providing

hybrid Web conferencing systems de-

signed to let users work with the

best of both service- and server-based

approaches.

“A carrier might remotely manage a

company’s onsite server,” said eDial

CEO Scott Petrack. This could enhance

management and keep companies from

having to oversee the system.

IETF Web conferencing standards

are based on its Session Initiation

Protocol for initiating and managing

interactive communication sessions

involving multimedia elements. SIP, a

software-implemented protocol, sets

up sessions, phone-call routing, authen-

tication, call parameters, and call trans-

fer and termination.

The IETF has formed the Central-

ized Conferencing (XCON) Working

Group (www.ietf.org/html.charters/

xcon-charter.html)—which includes

companies such as Cisco, Lucent

Technologies, and MCI—to develop a

standardized suite of protocols for

tightly coupled server- or service-based

or hybrid multimedia conferences that

require strong security and authoriza-

tion. The suite includes the IETF’s

SIMPLE (SIP for Instant Messaging

and Presence Leveraging Extensions)

and IP telephony standards.

XCON will replace many of the

hard-to-use proprietary APIs that cur-

rently support multivendor interoper-

ability, said the IETF’s Johnston.

Instead, the standard would create a

few interoperable APIs. In addition to

enhancing interoperability, XCON

would eliminate the time and money

companies spend to develop propri-

etary APIs.

XCON systems have a standardized

client and conferencing server. The

server enforces and manipulates

media-usage policies, including media-

composition rules that govern the

union of different media such as voice,

video, and IM during a session,

according to Johnston.

The IETF’s Media Policy Control

Protocol defines the controls available

to participants and the conference-

server administrator for manipulating

the media policy applicable to a spe-

cific session.

The media server includes mixers

that combine and properly mix video,

audio, and other streams and distrib-

ute them to participants. This is done

in either high-capacity digital signal

processors or lower-capacity, lower-

cost software.

I n d u s t r y T r e n d s

Vendors are working

together on wider

interoperability.

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XCON also works with a conference

policy, a set of rules that control vari-

ous aspects of a session, including the

access that conference administrators,

participants, and applications have to

various media and the ways that they

can communicate with one another.

For example, for a particular session,

XCON can include a list of users

authorized to participate in a confer-

ence. A node can also use XCON pro-

tocols to query a conference server to

learn what media types, such as

Internet telephony or video, it supports.

Conference administrators or par-

ticipants could use the IETF’s Confer-

ence Policy Control Protocol to manip-

ulate the conference policy.

The IETF expects to finish the

XCON protocols by later this year or

early next year.

endors have been working

together to offer wider confer-

encing interoperability. They will

probably adopt XCON within the

next 12 to 18 months, according to the

IETF’s Johnston.

In the future, Wainhouse’s Nilssen

predicted, companies will embed Web

conferencing technology in their work-

flow applications, such as those used

with sales or customer-relationship

management. This would let users eas-

ily initiate conferences if desirable in

conjunction with sales or CRM activ-

ities.

“I’m bullish,” said Nilssen. “I’m very

optimistic about Web conferencing as a

technology. I think it will become

embedded in the base fabric of how we

communicate and conduct business.”

However, the way people use Web

conferencing could affect its market-

place performance.

Said eDial’s Petrack, “If you ask peo-

ple in the enterprise to identify the least

productive thing they do, most will

respond ‘going to meetings.’ Any sys-

tem or service that is centered on meet-

ings, rather than collaborative work,

is always going to be a frustrating

niche product.” I

David Geer is a freelance technology

journalist based in Ashtabula, Ohio. Con-

tact him at david@geercom.com.

February 2005

Editor: Lee Garber, Computer,

l.garber@computer.org