Frequently Asked Questions

We have compiled some of the most frequently asked questions about videoconferencing and provided the answers below. If you have a question that is not found here, or within our Help section, please feel free to contact us so that we may assist you.

  1. Is there a difference between video conferencing and video teleconferencing?
  2. What are the primary considerations for purchasing video conferencing equipment?
  3. What is H.320 video conferencing?
  4. How do I know whether to buy an H.320 system or an H.323 system?
  5. What are most organizations buying today: H.320 or H.323 systems?
  6. What is a Codec?
  7. What is a Gatekeeper?
  8. What is a MCU?
  9. How do I buy video conferencing equipment?
  10. How many users or participants can I link together on a video conference?
  11. What types of telephone lines are required for a video conference?
  12. Can I use a regular telephone to participate in a video conference?
  13. Can I link callers on cellular phones into a multi-point video conference?
  14. How do I schedule video conferences when callers will be in different time zones?
  15. How do I connect to the codec directly?
  16. How do I protect my codec against people hacking into it on my LAN?
  17. What information will I need to have when I call into TANDBERG Technical Support?
  18. If I want to upgrade the software on my TANDBERG codec, how do I do it?
  19. How can I tell what software and what options I have on my system?
  20. How do I make telephone calls from my TANDBERG codec?
  21. How many sites can I connect using the internal MCU in the TANDBERG codec?
  22. My codec is asking me for an option key and I don't have it. How do I get one?


Is there a difference between video conferencing and video teleconferencing?
a) 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.
b) There is similar usage for phrases associated with teleconferencing. Teleconferences are called both audio conferences and teleconferences. In each, three or more telephone callers are linked together in a telephone call with all parties hearing one another and some or all parties interactively speaking.

What are the primary considerations for purchasing video conferencing equipment?
a)
Budget, Value, Vendors and their Partnerships, Equipment Manufacturers and Project Management.
b) Additional 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?
a)
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.
b) 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.
c) 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.

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?
a)
Most purchases today are for H.320 only or both H.320 and H.323.
b) 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 Codec?
Codec stands for "Coder/Decoder". It is a piece of equipment or software that both encodes an audio/video signal from an analog source (like a camera or microphone) and decodes the digital signal for replay as an analog signal (to a monitor or speakers.)

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.

What is a MCU?
MCU stands for Multipoint Control Unit. It is a device that is used to connect more than two video conferencing endpoints at a time into one video conference session. Much like a large audio conference, an MCU joins multiple video conferencing participants into a single conference, allowing them to see and interact with each other. The participants will either see one site at a time as each participant speaks, or they will see some form of a grid showing all of the participants in a split screen.

How do I buy video conferencing equipment?
a)
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 which 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.


b) 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.

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?
a)
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.
b) 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.

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.

How do I schedule video conferences when callers will be in different time zones?
a) There are a number of options you can use to help organize your video conferences. Some software packages that are available allow you to schedule attendees in different time zones. Each user is given their local time for the conference so as not to cause confusion.
b) Manually scheduling conferences is also common but the human error factor can cause a conference to fail because an important attendee is given the wrong time for their time zone. Additionally, a decentralized scheduling system or the absence of an enterprise wide scheduling system can result in double-booked conference rooms.

How do I connect to the codec directly? In order to connect to the codec directly, you must have the following: a computer terminal near the codec, a RS232 program on the computer (e.g. HyperTerminal or ProComm Plus) and a straight-through RS232 DB9 Male to DB9 Female cable. Plug the cable into the serial port of your computer and to Data Port 1 on the back of the codec. Open up your RS232 communications program and configure it for the appropriate "Com Port" on your computer (usually Com 1 or Com 2). The default communication settings are: 9600 baud, 8 data bits, 1 stop bit, no parity bit and flow control set to none. When configured, type "help or ?", hit Enter and you will get a list of commands.

How do I protect my codec against people hacking into it on my LAN?
You can assign an IP password on the codec that will prevent anyone from logging into the codec over the web page, telnet and ftp session. To implement the IP password on the codec, either telnet or connect directly (by using a DB9 - DB9 straight through cable to Data Port 1 of the codec) to the codec and type ippassword where is the password you would like to assign. You can also assign a password through the security menu of the user interface or through the web interface of the system. To remove the password, you can either connect to it locally or you can remove it in the menu system. If you forget your IP Password, you have to connect to the codec directly using a RS232 cable. To clear the password type "ippassword".

What information will I need to have when I call into TANDBERG Technical Support?
You will need to provide the system serial number to your system which is found on the back of the codec above the power switch or on the bottom of the system. If you can not find your system serial number you will need to have your TANDBERG order number from when you purchased the system. This number will start with a 'B, US or 5' so that TANDBERG Technical Support personnel can assist you.

If I want to upgrade the software on my TANDBERG codec, how do I do it?
In order to upgrade the software on your TANDBERG codec, you need to call Technical Support with the following information: hardware serial number (see above) and codec serial number (the serial number of the system is either on the back of the system by the power switch or underneath the system - e.g. a set top system has the s/n underneath). Download the software for the codec by going to the TANDBERG ftp website http://ftp.tandberg.net ' and contact your maintenance provider for the software upgrade Release Key.

How can I tell what software and what options I have on my system?
Press the 'menu' key and the up arrow key to access the Quick Menu for status. Use the left arrow key to select the system information icon. On this status screen you will see what software version you are currently running along with the options installed on the system.

How do I make telephone calls from my TANDBERG codec?
Begin the call as you would any normal video call. Before you press the Connect key, select the green telephone icon at the bottom of the menu.

How many sites can I connect using the internal MCU in the TANDBERG codec?
If you have the Multisite option installed on your codec, you can establish a call with up to 6 video sites (including yourself) and 5 audio sites depending on the product you are using.

My codec is asking me for an option key and I don't have it. How do I get one?
Contact your maintenance provider with the codec serial number and hardware serial number and they will inform you of what options you are supposed to have on your system and, if necessary, give you the appropriate option key for your system.

 

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