A procedure for adding order to the exchange of data. A protocol is a specific set of rules, procedures, or conventions relating to the format and timing of data transmission between two devices. Basically a set, standard.

Coder-Decoder. A device that "codes" analog signals into digital bit streams for transmission over digital circuits then "decodes" the bits into analog waves at the receiving end. A Codec in videoconferencing is usually the users endpoint.

The capacity or speed of a telecommunications transmission medium (e.g., 64 Kbps). Basically how much, and how fast, can you send and receive data.

Suite of standards for multimedia conferencing on narrowband switched digital networks. Commonly used with ISDN service. Early deployment for video conferencing over digital telephone lines. A bit costly as there is a charge for the lines and a per minute rate charge. ISDN is still very popular in corporations. The Video Portal “bridges” ISDN connections all over the world to ANJ members free of charge.

Suite of standards used for ATM narrowband conferencing. Older generation video conferencing that required specialized V-Switches, V-Rooms, and end points. More expensive than IP (H.323).

Suite of standards for multimedia conferencing on traditional IP networks. Newest protocal being used for video conferencing. Uses IP technology. Less expensive to deploy than ISDN or ATM.

Older proprietary “closed” video network that was unable to cross LATA boundaries used in New Jersey early deployment for distance learning. IDLS is in its end of life. ANJ Video Portal still bridges IDLS in North Jersey for existing customers. Worked like a two way cable system.

Integrated Services Digital Network. H.320. A digital telephone line used for voice, data and compressed video.

ITU standard for video coding for videoconferencing. H.261 is a discrete cosine transform (DCT) based algorithm for video in the 64kb/s to 2mb/s range. All H.323 compliant video conferencing systems are required to support this codec.

ITU standard for video coding within videoconferencing. H.263 offers better compression than H.261, particularly in the low bit rate range used by modems.

Asynchronous Transfer Mode. H.321. A high bandwidth packet-based network technology deployed as the backbone for Access New Jersey. A connection oriented service that transmits voice, data, and video traffic in fixed cell lengths at high speeds into the gigabit range. ATM video conferencing utilizes V-Switches and V-Rooms and is more expensive than the newer IP H.323.

See H.323 protocol. IP video conferencing can be done over the commodity Internet without QoS or can be done on a robust private network such as Access New Jersey that can deliver a high quality of service for video conferencing. Access New Jersey’s Video Portal can also “bridge” to the commodity Internet.

Video conferencing done over the World Wide Web using IP. Convenient, but lacks QoS. Inexpensive and accessibility is what makes this interesting as a video conferencing technology.

The term "Webcasting" is used to describe the ability to use the Web to deliver live or delayed versions of sound or video broadcasts. This is a one way service delivering video and audio and usually highly compressed.

Streaming video is a sequence of "moving images" that are sent in compressed form over the Internet and displayed by the viewer as they arrive. Streaming media is streaming video with sound. With streaming video or streaming media, a Web user does not have to wait to download a large file before seeing the video or hearing the sound. Instead, the media is sent in a continuous stream and is played as it arrives.

In telecommunication networks, a bridge is a product that connects a local area network (LAN) to another local area network that uses the same protocol (for example, Ethernet or Token Ring). In Video conferencing, a bridge is a product that connects an endpoint or codec to another endpoint or codec that uses the different protocol or that is on a different network. The Access New Jersey Video Portal provides “bridging” free of charge to all ANJ members.

Contact the Video Portal. This service is free to all ANJ members.

Communication that takes place between two video sites. Usually no bridging is needed and sites “dial” each other directly without the need to contact the Video Portal. This is easy when both sites are on the same network and run the same protocols.

A video communications connection between more than two sites via a Multipoint Conference Unit (MCU) or bridge. When “multiple” sites need to connect for a group conference. This service is provided free of charge to all ANJ members by the Access New Jersey Video Portal.

An inverse multiplexer combines multiple network channels to one aggregate higher speed pipe for transmitting video or data. It does this dynamically, to provide bandwidth on demand, in multiples of 56 or 64 Kbps. This functionality is used in video conferencing usually with ISDN H.320 equipment to “mux” together ISDN digital lines for 384 K conferencing.

A firewall is a set of related programs, located at a network gateway server or standalone device that protects the resources of a private network from users from other networks. (The term also implies the security policy that is used with the programs.) Firewall’s filter unwanted data traffic to help secure networks.

Network Termination Adaptor. Used to terminate ISDN equipment to Tele-Co digital phone lines.

Local Access Transport Areas. There are three LATAs in New Jersey (Newark/Atlantic City/Mt. Laurel). Telecommunications services between LATA must be provided by a Long Distance Carrier (Verizon is now a Long Distance carrier in NJ).

Multipoint Conference Unit, sometimes referred to as a "bridge." An MCU can usually “bridge” between protocols, provide multi-point conferences, or both at the same time. Access New Jersey Video Portal utilizes a high quality robust MCU in each of the three LATAs in New Jersey for redundancy. MCU use is provided free to all ANJ members thru the Video Portal. The Video Portal also provides “local” ISDN dial in for all ANJ members saving them long distance charges for ISDN users.

A gateway is a network point that acts as an entrance to another network. An MCU is acting like a gateway when it “bridges” between to protocols or networks.

A gatekeeper is an H.323 entity on a LAN that provides address translation and control access to the LAN for H.323 terminals and gateways. The gatekeeper can provide other services to the H.323 terminals and gateways, such as bandwidth management and locating gateways. A gatekeeper maintains a registry of devices in the multimedia network. The devices register with the gatekeeper at startup and request admission to a call from the gatekeeper.

A router is a device or, in some cases, software in a computer, that determines the next network point to which a packet should be forwarded toward its destination. The router is connected to at least two networks and decides which way to send each information packet based on its current understanding of the state of the networks it is connected to.

Calling speeds are determined by bandwidth and end point equipment capabilities at each site. Basically the higher the calling speed the higher the quality of the video, the more bandwidth needed. Calling speeds are usually 128, 256, 384, 512, and 768. Access New Jersey Video Portal can accommodate 128 to 768 video calls. This is determined by the participants’ capabilities.

Quality of service. This is accomplished by controlling the networks latency, congestion, bandwidth, and throughput. When conferencing over the Internet QoS is hard to achieve. When using the Access New Jersey network QoS is controlled by Verizon Video Portal.

Virtual Private Network. A virtual private network (VPN) is a way to use a public telecommunication infrastructure, such as the Internet, to provide remote offices or individual users with secure access to their organization's network.

Videoconferencing that allows the participants to see all of the other participants at the same time in the videoconference.

Videoconference where endpoints are switched on voice-activated audio so you see only participant speaking.