rcuit. During the periods of heavy traffic, TASI can improve line efficiency by 45% to 80%. Tbps (terabits per second) Trillions of bits per second. TBRPF (Topology Broadcast Based on Reverse-Path Forwarding) A proactive link- state routing protocol designed for mobile ad hoc networks. It provides hop-by-hop routing along minimum-hop paths to each destination. TCAP (Transaction Capabilities Applications Part) A system that supports intelligent network service by enabling the exchange of non-circuit-related information between different signaling points (i.e., network nodes). T-carrier The North American standard of the PDH, a TDM digital transmission system. T-carrier is a PCM system that uses 64Kbps per channel as the basis of the hierarchy. Higher levels reflect aggregation of the 64Kbps channels. T-1 is a 1.544Mbps 24-channel communica- tions circuit; T-2 is a 6.312Mbps 96-channel communications circuit; T-3 is a 44.736Mbps 672-channel communications circuit; and T-4 is a 274.176Mbps 4,032-channel communica- tions circuit. TCP (Transmission Control Protocol) One of the core protocols of the Internet Protocol suite. Using TCP, applications on networked hosts can create connections to one another, over which they can exchange data. TCP supports many of the Internet's most popular application protocols and applications. TCP stack A suite of multiple protocols used to exchange information between computers. The Internet and most commercial networks run on the TCP stack. TCP/IP (Transmission Control Protocol/Internet Protocol) The most widely used internetworking protocol. It ensures that packets of data are delivered to their destinations in the sequence in which they were transmitted. TCP roughly corresponds to Layer 4 (the transport layer) of the OSI model. It provides reliable transmission of data. IP corresponds to Layer 3 (the network layer) of the OSI model and provides connectionless datagram service. TD-CDMA (Time Division Code Division Multiple Access) A 3G combined time divi- sion and CDMA scheme used by