Web conferencing may be used as an umbrella term for various types of online collaborative services including web seminars ("webinars"), webcasts, and peer-level web meetings. It may also be used in a more narrow sense to refer only to the peer-level web meeting context, in an attempt to disambiguate it from the other types of collaborative sessions. Terminology related to these technologies is inexact, and no generally agreed upon source or standards organization exists to provide an established usage reference. In general, web conferencing is made possible by Internet technologies, particularly on TCP/IP connections. Services may allow real-time point-to-point communications as well as multicast communications from one sender to many receivers. It offers data streams of text-based messages, voice and video chat to be shared simultaneously, across geographically dispersed locations. Applications for web conferencing include meetings, training events, lectures, or presentations from a web-connected computer to other web-connected computers.
Installation and operation
Web conferencing software is invoked by all participants in a web meeting. Some technologies include software and functionality that differs for presenters and attendees. Software may run as a web browser application (often relying on Adobe Flash, Java, or WebRTC to provide the operational platform). Other web conferencing technologies require download and installation of software on each participant's computer, which is invoked as a local application. Many web conferencing vendors provide the central connectivity and provisioning of meeting "ports" or "seats" as a hosted web service, while others allow the web conference host to install and run the software on its own local servers. Another installation option from certain vendors allows for use of a proprietary computer appliance that is installed at the hosting company's physical location. Depending on the technology being used, participants may speak and listen to audio over standard telephone lines or via computer microphones and speakers. Some products allow for use of a webcam to display participants, while others may require their own proprietary encoding or externally provided encoding of a video feed (for example, from a professional video camera connected via an IEEE 1394 interface) that is displayed in the session. Vendor-hosted web conferencing is usually licensed as a service based on one of three pricing models: a fixed cost per user per minute, a monthly or annual flat fee allowing unlimited use with a fixed maximum capacity per session, or a sliding rate fee based on the number of allowed meeting hosts and per-session participants (number of "seats"). Presentation of visual materials most often is accomplished through one of two primary methodologies. The web conferencing software may show participants an image of the presenter's computer screen (or desktop). Again, depending upon the product, the software may show the entire visible desktop area or may allow selection of a physical area or application running on the presenter's computer. The second method relies on an upload and conversion process (most commonly consisting of Microsoft PowerPoint files, other Microsoft Office electronic documents, or Adobe PDF documents).
The term "webinar" is a portmanteau of web and seminar, meaning a presentation, lecture, or workshop that is transmitted over the web. The coined term has been attacked for improper construction, since "inar" is not a valid root. Webinar was included on the Lake Superior University 2008 List of Banished Words, but was included in the Merriam-Webster dictionary that same year. The term "webcast" derives from its original similarity to a radio or television broadcast. Early usage referred purely to transmission and consumption of streaming audio and video via the World Wide Web. Over time, webcast software vendors have added many of the same functional capabilities found in webinar software, blurring the distinction between the two terms. Webcasts are now likely to allow audience response to polls, text communication with presenters or other audience members, and other two-way communications that complement the consumption of the streamed audio/video content.
Other typical features of a web conference include:
|Slideshow Presentations - where images are presented to the audience and markup tools and a remote mouse pointer are used to engage the audience while the presenter discusses slide content.|
|Live or Streaming Video - where full motion webcam, digital video camera or multi-media files are pushed to the audience|
|VoIP - Real time audio communication through the computer via use of headphones and speakers.|
|Web Tours - where URLs, data from forms, cookies, scripts and session data can be pushed to other participants enabling them to be pushed though web-based logons, clicks, etc. This type of feature works well when demonstrating websites where users themselves can also participate.|
|Meeting Recording - where presentation activity is recorded on the client side or server side for later viewing and/or distribution.|
|Whiteboard with annotation (allowing the presenter and/or attendees to highlight or mark items on the slide presentation. Or, simply make notes on a blank whiteboard.)|
|Text Chat - For live question and answer sessions, limited to the people connected to the meeting. Text chat may be public (echoed to all participants) or private (between 2 participants)|
|Polls and surveys (allows the presenter to conduct questions with multiple choice answers directed to the audience)|
|Screen sharing/desktop sharing/application sharing (where participants can view anything the presenter currently has shown on their screen. Some screen sharing applications allow for remote desktop control, allowing participants to manipulate the presenters screen, although this is not widely used.)|
Web conferencing technologies are not standardized, which has reduced interoperability and transparency and increased platform dependence, security issues, cost and market segmentation. In 2003, the IETF established a working group to establish a standard for web conferencing, called "Centralized Conferencing (xcon)". The planned deliverables of xcon include:
|A binary floor control protocol. Binary Floor Control Protocol (BFCP) published as RFC 4582|
|A mechanism for membership and authorization control|
|A mechanism to manipulate and describe media "mixing" or "topology" for multiple media types (audio, video, text)|
|A mechanism for notification of conference related events/changes (for example a floor change)|
Web conferencing is available with three models: hosting service, software and appliance.
An appliance, unlike the online hosted solution, is offered as hardware. It is also known as "in-house" or "on-premises" web conferencing. It is used to conduct live meetings, remote training, or presentations via the Internet.