As data flows increase, so do the requirements for transfer speed, processing time and presentation. Today, no major company, public institution or scientific organization having agencies, branches, etc. can operate without huge amounts of data exchange. In many cases, the capabilities of public telephone switchboards prove inadequate, and communication via leased lines is viewed as a better solution. A TF line is simply a telephone connection made permanent by the service operator.
Connection is obtained immediately upon picking up the phone or initializing a modem.
Being essentially a regular telephone line, a TFL travels through switchboards and other equipment operating within the telephone system. Therefore, it is exposed to the same speed limitations as a regular switched connection. The only advantage of a TFL is that the data exchange service is available at any time and no time is lost in establishing connection. A leased coppez line is simply a pair or several pairs of telephone wires thrown between two offices. The second option is usually cheaper and faster to accomplish.