How Teleconferencing Works

In the past few years, corporations have gotten bigger and more spread out. Many American employees -- more than 44 million in 2004 -- also do at least some of their work from home [ref]. Since offices and employees can be thousands of miles apart, getting everyone into the same room for meetings and training has become decidedly impractical for a lot of companies.

That's why teleconferencing -- the real-time exchange of information between people who are not in the same physical space -- has become such a big industry. The American audio conferencing industry alone reported $2.25 billion in revenue in 2004 [ref]. Through teleconferencing, companies can conduct meetings, customer briefs, training, demonstrations and workshops by phone or online instead of in person.


In this article, we'll look at different types of teleconferencing, from conference calls to online meetings.

The simplest phone teleconference is a three-way call, available in many homes as a service from the telephone company. Another very simple (but not necessarily effective) method is to have two groups of people talk to one another via speakerphone. The limits of three-way calling and the sound quality of speakerphones make both of these options impractical for most businesses.

Conference calls let groups of people -- from a few to hundreds -- communicate by phone. Banks and brokerages often use conference calls to give status reports to large numbers of listeners. Other businesses use conference calls to help coworkers communicate, plan and brainstorm. To connect to the call, attendees call a designated number (MeetMe conferencing), or an operator or moderator calls each participant (ad hoc conferencing).

Conference calls connect people through a conference bridge, which is essentially a server that acts like a telephone and can answer multiple calls simultaneously. Software plays a large role in the bridge's capabilities beyond simply connecting multiple callers.

A company can have its own bridge or can contract with a service provider for conference call hosting. Providers frequently offer add-on features for conference calls, such as:

  • Attendee polling
  • Call recording ­
  • In-call operators or attendants

Companies using Voice over IP (VoIP) telephones can also host conference calls themselves if the VoIP software supports them.

Many phone conferencing systems require a login and personal identification number (PIN) to access the system. This helps protect confidential and proprietary information during the call.

Video phones can add a visual element to conference calls, but businesses often need to share other visual information.


Teleconferencing Online

Teleconferencing lets large companies work more effectively. Learn different ways of teleconferencing, the equipment you need and read teleconferencing reviews.
Courtesy Star Conferencing

Web conferencing allows people to communicate through text and video in addition to audio. The simplest web conferencing methods use chat and instant messaging programs to host text-based group discussions. More sophisticated programs exchange visual information with webcams and streaming video. Some allow people to share documents online.

Companies can either purchase conferencing software and host their meetings themselves or use a hosting service. Hosting services provide the software and server space on which to conduct meetings. Either way, the company or the hosting service must have software to coordinate the meeting and ample server space and bandwidth to accommodate it.


Web conferencing programs combine tools already common to web pages and Internet communication. They bundle these tools into one interface to create an interactive meeting environment. These tools include:

Some programs are entirely computer- and Internet-based. Others use the telephone system to distribute audio content. To participate in the online meetings, participants must have:

  • A computer
  • An Internet connection
  • A telephone, if audio content is not provided online

If the conferencing program relies on Internet-based audio chat and webcam feeds, the participants' PCs should have:

  • Microphones
  • Webcams
  • Video capture cards

In general, every online presentation or meeting has a moderator and attendees. The moderator sets the time and date of the meeting, prepares the content and makes sure everything works properly before the meeting begins. Attendees can either view the presentation without giving feedback or can collaborate, based on the settings and capabilities of the programs. Often, moderators can record the presentation for later viewing and can pass their moderator capabilities to attendees during the meeting.

But what can people do in these virtual meeting rooms? Let's find out.


Web Conferencing Features

Some web conferencing programs can replicate real-world whiteboards.

Web conferencing programs come with a tremendous variety of features and capabilities. Some can merge with a company's existing e-mail, calendar, messaging and office productivity applications. Some allow attendees to view the presentation in their regular web browser without installing any additional software.

Depending on the software, people can:


  • View slide presentations from programs like PowerPoint
  • Draw or write on a common whiteboard by using their computer mice or typing
  • Annotate images and diagrams using the same whiteboard principle
  • Transmit still pictures or video to other attendees via a webcam (This increases the required bandwidth and can sometimes slow the transfer of the presentation.)
  • View information from the moderator's computer desktop using screen sharing
  • Share documents, often even if attendees don't have the software that created them, using application sharing
  • Hold interactive question-and-answer sessions that integrate video and audio
  • Send public or private messages through instant messaging
  • Annotate or modify documents and spreadsheets from compatible applications
  • Transfer files between attendees
  • Ask and answer questions through audio chat (as an integrated part of the software) or by phone

Since these meetings take place over the Internet, programs include options for security and encryption. Most programs require moderators and attendees to use a login name and password to access the meeting. Some use SSL or TLS encryption to protect data. Some companies also host web conferences on internal servers so that the data stays behind the corporate firewall. The moderator or host can monitor who is participating in the conference through sign-in logs and roll calls.

A Typical Online Meeting

Web conferences can vary dramatically depending on software, hosting and how the moderator runs the meeting. Here are the basic steps used with many meeting programs:

  1. The moderator gathers content for the meeting, including spreadsheets, documents and presentations from other applications.
  2. The moderator sets a time and date for the meeting and uses the meeting software to invite attendees via e-mail.
  3. The attendees accept the invitation, and their calendar programs add the meeting to their calendars.
  4. The meeting moderator opens the conferencing software before the meeting is scheduled to start and makes sure the connections and content are working properly.
  5. When the meeting time arrives, the attendees click on the URL in their invitation email to go to the meeting.
  6. The visual portion of the meeting takes place in the meeting software or in a web browser.
  7. The moderator and participants communicate by phone, voice chat or instant messenger during the meeting.
  8. At the end of the meeting, the moderator and attendees close their programs or browser windows and sign off.

For more information about telework, teleconferencing and related topics, check out the links on the next page.


Lots More Information

Related HowStuffWorks Articles

More Great Links

  • Conferral
  • Conference Bridge Configuration
  • Federal Highway Administration: Public Involvement Techniques for Transportation Decision-Making
  • Federal Standard 1037C
  • GoToMeeting
  • Infrastructure Equipment: Conferencing Bridge
  • Lewicki, Anna. "Video Teleconference Allows Soldier to Wed from Bosnia." National Guard, February 2004. Find Articles.
  • Macromedia Breeze
  • McConnell, Brian. "Telecom Tips: Building your Own Conference Bridge." April 29, 2005. O'Reilly Developer Weblogs.
  • Microsoft Office Live Meeting
  • Microsoft Windows Netmeeting
  • Meserve, Jesse. "Telemedicine helps victims of stroke." May 23, 2005, Network World.
  • Raindance Meeting Edition
  • Sonexis: Evaluating Conferencing Solutions
  • Telework Facts
  • Understanding Telecommunications
  • WebEx
  • Wiredred Software