Speed rate: Transmission speed of audio video information and data in a videoconferencing communication. In professional quality, the most common speed rate are:
- 384 Kb/s for a very high audio-visual quality, for instance 15 images per second in CIF resolution with a bandwidth of 7 kHz ( 2 times better than phone sound)
- 256 Kb/s for a medium audio-visual quality.
- 128 Kb/s for a minimal audio-visual quality, for instance 10 images per second in CIF resolution with a bandwidth of 3 kHz.

Firewall: Protection element of a private network in interface with the Internet.

Audio format: The transmitted videoconferencing sounds are coded according to 3 quality families. There is the phone based quality of 3 kHz ( G711, G728, G723 norms), the bandwidth quality of 7kHz (G722, PT724, PT716 norms), the 14 kHz quality ( 14 Siren norm).

Video format: The videoconferencing images are CIF format. They are spatially and temporally coded according to H261 and H263 coding norms. The H263 norm is more recent and more efficient ( better spatial and temporal result) in low speed rate (128 Kb/s) than the H261 norm. The given video quality is proportional to the transmission speed rate. Therefore a good result will be obtained in 384 Kb/s flow and dissipates quite linearly when the speed rate is reduced to 256Kb/s and even more to 128Kb/s.

Intranet: Virtual private network for applications shared between several distant sites in HTLM mode accessible by Web navigator.

IP: Internet Protocol. Asynchronous transmission mode per packet used on the Internet and on private Ethernet networks.

LAN: Local Area Network. Local company Ethernet network.

Multipoint port: Multipoint videoconferencing server resource allowing the connection of a distant site to a multisite meeting.

ISDN: Digital network with service integration. Public network using the standard phone line copper pair to dispatch a 128Kb/s synchronous and symmetric speed rate net by basic access (144Kb/s gross). The 256Kb/s and 384Kb/s speed rate are realised by groups of 2 or basic access. 2Mb/s primary accesses are also available.

T120: Transfer norm of videoconferencing data processing. The data can be exchanged, in low speed rate ( LSD mode up to 6Kb/s), or in high speed rate ( HSD mode up to 38Kb/s) or, in standard mode ( MLP, without speed rate limitation)

Videostreaming: Multimedia content diffusion service on private or public IP network ( internet). Declinable on 2 modes: on demand, on real time, for instance to participate in a conference, or on differed.

WAN: Wide Area Network. Private IP network extended to various distant establishments from the same society trough hired public transmission parts.