The telecommunications field is a vast field that contains terms and acronyms which can be confusing to those who are not familiar with the terminology. Therefore, the following paragraphs will compare and explain some common terms used when referring to the telecommunications field and will entail some old technology with some new. To be included within the discussion is comparisons of telephone dialing sounds, Wide Area Telecommunications Services (WATS) versus leased lines, Private Branch Exchanges (PBX) or Centrex, and the International Organization for Standardization-Open Systems Interconnection (ISO-OSI) model.
What are the differences between Rotary and Dual Tone Multi-frequency (DTMF)? Rotary dialed phones were round and "spun" to make a phone call. The disk had the numbers 0-9 and one had to place a finger in the hole next to the number they wanted to select and turn the dial completely around then let go. When the disk spun back to its original position it would create a series of frequency pulses that corresponded to the number dialed and was known as "pulse dialing." The phone company switching network would recognize the number of "clicks or pulses' sent and would switch to the appropriate line.
On the other hand DTMF uses a "tone dialing' method to place a call. A push button phone uses the "tone" method of dialing. Each time a number button is pushed on the phone, the circuitry in the phone makes a two toned sound for each number and sends that sound to the phone company switching network for validation and to be patched through to the correct line (Zeebar, 2007).
What are Wide Area Telecommunications Service (WATS) and leased lines and how are they different? Wide Area Telecommunications Service is a special "dedicated" line for individuals or company's that want to have to luxury of having a designated number that would allow for incoming