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Video & Web Conferencing F.A.Q.
Is there a difference between video conferencing and video teleconferencing? When describing video conferencing systems, there is a common interchanging of words that mean the same thing. Video conferencing is the same as video teleconferencing. The phrases are both used to describe a meeting between parties in different locations wherein the meeting participants use communications equipment to both see and hear one another as they interact. What are the primary considerations for purchasing video conferencing equipment? Some considerations include room configuration, the number of people involved in a video meeting at one time, and network selection (H.320 or H.323). Also important are room scheduling, system maintenance, product selection and audio levels. What is H.320 video conferencing? H.320 is the name of the standard for video conferencing using what are called "switched services" like ISDN and Switched-56. The standard was established in 1990. There are a number of protocols related to the H.320 standard. This series of standards govern basic video communications including graphical communications and audio over commonly used time division multiplexed (TDM) circuits. This H.320 type of video conferencing has historically been the most popular and flexible. The standard governs communications over digital channels, similar to those your telephone uses deep within the telecommunications network. Frequently, in order to ensure a high degree of picture and sound quality, a technique called "inverse multiplexing" is used to aggregate channels for higher bandwidth. H.320 video communications systems are often used on networks where usage charges apply such as on networks that use ISDN services from local and long distance telephone companies. What is H.323 video conferencing? H.323 is the name of the standard for video conferencing using an IP network as the communications link. H.323 video conference communication uses the Real-Time Protocol (RTP/RTCP) and it enables the use of video conferencing over IP networks, LANs and even over the Internet. Each system connects to others by dialing an IP Address rather than by using a telephone number (as in H.320 communications). Using H.323 image quality can be as good or better than H.323 video conferencing of comparable bandwidth. There are a number of issues with respect to H.323 video communications that do not affect H.320 communications. For example, the general nature of IP networks does not assure bandwidth availability that is essential for quality H.323 video conferencing. Several remedies are available to overcome this constraint, some of which include re-engineering entire corporate IP backbone networks to accommodate video conferencing. How do I know whether to buy an H.320 system or an H.323 system? Most systems today are H.323 capable. Some manufacturers charge extra to enable H.320 ports on their systems. Depending on your network design, it is usually best to have both H.323 and H.320 capability. This would allow for quick and easy H.323 setup in a campus environment with the ability to communicate securely outside of the campus with ISDN or other digital telephone lines using the H.320 protocol. What are most organizations buying today: H.320 or H.323 systems? Most purchases today are for H.320 only or both H.320 and H.323. Today, there is a push for widespread adoption of H.323 as a video communications standard. This has particular appeal because IP (H.323) networks are believed to be far less costly to operate than switched digital communications (H.320) networks. However, cost are falling dramatically for switched digital calling around the globe, and because of important H.323 issues (such as firewall and bandwidth constraints) it is not certain that H.323 will become dominant. Instead, it is likely that H.320 and H.323 communications will both be used widely and gateways or gateway features will become standard in most networks. What is a Gatekeeper? A Gatekeeper is a software component that allows you to register each of your H.323 video conferencing users. This software allows you to set restrictions on bandwidth usage and function. You can define these settings on a case-by-case basis per site as each site registers (i.e. no restrictions on the company president), or on a global setting. This can be a good way to manage your H.323 video conferencing network and minimize the impact on your LAN. With a Gatekeeper, you can use aliases such as "Bill Smith" to connect parties rather than the more abstract IP address. A fictitious phone number such as "555-1111" can also be assigned as an IP "alias" and thus an IP network could be made to look and feel like a telephony network. How do I buy video conferencing equipment? Shop for a quality vendor in the marketplace and ask them to guide you through the purchase and installation of your equipment. A quality vendor will be able to list several well-known customer names for whom they have provided products and services for a number of years. Start with a search on the Internet, then yellow pages, and look for articles in trade magazines that list names of industry vendors. Once you make contact with a potential vendor, ask them for the names of a few of their competitors. Product selection can be quite difficult with many details of system operation left out of discussions by the manufacturers. A good vendor knows all the best products in the industry and should be able to point out the best features of each. Keep in mind that vendors get different pricing from each manufacturer and ask the vendor to describe their relationships with manufacturers. An honest vendor is likely to be a good vendor so pay particular attention to which products they recommend versus which products they get most benefit from selling. Industry products and manufacturers change. Good vendors stay in business through many product changes and throughout changes in product leadership. For this reason, it is sometimes better to select a good vendor than it is to select a good product. The quality vendor will always offer the best products but when products become old and outdated, a good vendor will still continue to provide support and technical assistance. Ask your vendor to describe how they support obsolete products and how they manage product line changes from the manufacturers. Another method is to visit trade shows and ask manufacturers for demonstrations. At trade shows, each manufacturer's products can be easily compared without scheduling separate appointments. Ask about the most significant features available on each product. Then, be sure to ask how each system is better than the competitor's systems. Usually, each manufacturer will claim their features are superior so you should be sure to ask if you can operate the equipment yourself to draw your own conclusions. Once you have selected the equipment that meets your needs, ask the manufacturer for the names of three to five companies that sell their products. More companies selling a manufacturer's products are better than less. You will want to know the marketplace has accepted their products. Market acceptance means you will be able to find answers to both technical and administrative questions, spare parts will be available and perhaps pricing will be more favorable. Some manufacturers sell their products directly to customers. This sales approach usually means the customer has limited alternatives for service and less pricing alternatives. It also means their products may be too complex for 3rd parties to sell. If I don't want to buy equipment, how can I use video conferencing? There are services available that will lease the necessary equipment if your need is a short one. Or, you can pay for use of a video conference equipped room. How many users or participants can I link together on a video conference? Some video conferencing codecs are multi-site enabled. This means they can connect additional sites without the need for a multi-point conference unit (MCU/Bridge). While multi-site conferencing may be a feature on an endpoint, we recommend using an MCU when connecting more than 3 sites in a video conference. This will typically ensure higher quality video and bandwidth availability. What types of telephone lines are required for a video conference? For H.320 video conferencing, BRI ISDN lines either from your local Telco, or from your company's PBX are required. In some applications with special networks, leased T-1 lines, ATM networks, Primary Rate ISDN and/or Switched-56 circuits will also work well. For H.323 communications, a LAN (IP) connection, available bandwidth and some minimum amount of assured bandwidth is required. For business-grade communications no less than 128K of available bandwidth is essential. A VPN tunnel through the Internet may also be required for communication over a Wide Area Network. Can I use a regular telephone to participate in a video conference? Yes, however, if your organization uses a video conference bridge (MCU), it may not support mixing participants in this manner (i.e., video participants and telephone participants). You may be required to use an outside vendor, to link your audio and video conferences. TKO provides this service and we will be happy to answer further questions on "mixed" conferences. Can I link callers on cellular phones into a multi-point video conference? It is possible to connect someone on a cellular telephone into a conference, however, that connection is usually quite poor. Cellular callers often inject poor audio quality into a conference call or drop out of a conference due to signal loss. What is web conferencing? Web conferencing refers to innovative technologies that allow people to communicate or "conference" over the Internet. Web conferencing is based on tools that most of us use on a daily basis - our PC, our telephone, and the Internet. What do I need to be able to conduct a web conference? Practically anyone can conduct a basic web conference because all that is required is a computer with a Java-enabled browser, a phone, and an Internet connection of 56kbps or better. Are there different types of web conferencing? The three basic formats offered by web conferencing are meeting, presentation and collaboration. How are web conferencing solutions purchased? Purchasing options include "renting" or licensing web conferencing software that is hosted on the vendor's server; purchasing the software and hosting it on your own server; purchasing software from a reseller; or working with a full-service vendor who will supply the planning, marketing, and production of your event as well as the web conferencing software. How is web conferencing used for conducting a meeting? Two or more people can conduct a meeting over the Internet using web conferencing technologies to view a shared document, stream audio and/or video, use VoIP, or use a web-based chat technology. How is web conferencing used for giving a presentation? A presenter can present content over the Internet using a form of slide show presentation, web-based chat and streaming audio and/or video. Attendees view the presentation by logging into the web conference, and communicate with the moderator either through their phones or through web-based chat. The moderator can interact with participants, view attendee lists, and manage the communication during the event. What is a webcast? Another type of presentation is a webcast, in which a live event is recorded and streamed over the Internet, or archived for viewing at a later time. What is voice-over-IP? Voice-over-IP (VoIP) is the technology that allows users to exchange voice data over an Internet connection through their computers. |
