Time Division Multiplexing (TDM)
Native TDM is a type of digital multiplexing that transfers two or more data streams transmitted simultaneously as sub-channels in one communication channel. This is perfect for circuit switched networks such as Public Switched Telephone Network (PSTN) where there is a need to transmit multiple subscriber calls along the same transmission medium. TDM allows switches to create channels (or tributaries), with a transmission stream. A standard DSO voice signal has a data bit rate of 64Kbits. TDM takes frames of the voice signals and multiplexes them into a TDM frame which runs at a higher bandwidth.
Internet Protocol (IP)
The Internet Protocol (IP) is a data-oriented protocol used for communicating data across a packet-switched network.
IP is a network layer protocol in the internet protocol suite and is encapsulated in a data link layer protocol (e.g., ethernet). As a lower layer protocol, IP provides the service of communicable unique global addressing amongst computers.