T

	T1
	In North America, T1 service delivers 1.544 Mbps, whereas ISDN service delivers 128 kbps. The data travels over the line at the same speed, but for T1 lines, the capacity is twelve times that of ISDN. Typically channelized into 24 DS0s, each capable of carrying a single voice conversation or data stream. The European T1 or E1 transmission rate is 2.048 million bits per second.
	T3
	In North America, a digital channel which communicates at 45 Mbps, or 28 T1 lines.
	T1 PRI line
	A T1 line that uses 23 B channels for user data, and one 64 kbps D channel for ISDN D-channel signalling. This type of PRI line is a standard in North America, Japan, and Korea.
	TDMA (Time division multiple access.)
	Refers to a form of multiple access where a single carrier is the shared by many users. Signals from earth stations reaching the videoconference consecutively are processed in time segments without overlapping.