While originally conceived as a transport network for 64-kbis digitized voice, it is now possible to dial up point to point digital connections whose bandwidth ranges from 64 kbps to 3 Mb/s and beyond. Two significant enhancements to TDM networking have made this possible. The first is newly-developed software for digital TDM switches that allows dialed connections to exceed the original design channel rate of 56 or 64 kb, allowing carriers to offer dialed wideband services. The second is the use of specialized equipment that resides at the user’s premises to allow multiple independent digital connections to be “combined” to create a single, higher-speed end-to-end connection. This technique is known as inverse multiplexing, and the equipment that performs it is called an inverse multiplexer.
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