DTMF tones, or Dual-Tone Multi-Frequency signaling, are audible tones that are used by touch-tone telephones to identify which number key was pushed by the operator. DTMF tones have been used since 1963 and are used by all standard touch-tone telephones in the United States as well as in many other countries around the world. DTMF …
SMS, or Short Messaging Service, is a text-based messaging service that is used by over 2.4 billion mobile phone users worldwide. SMS allows users to send and receive text-based messages, pictures, videos, and audio clips from other mobile phone users and desktop computer users who have applications that can interact with mobile phones. SMS differs …
CNA stands for Customer Name and Address. The CNA number is a phone number for telephone company personnel to call and get the name and address for a phone number. If a telephone lineman finds a phone line he does not recognize, he can use the ANAC Number to find its phone number and then …
Telephone switches route calls through the PSTN (Public Switched Telephone Network). When you pick up the handset on your home telephone, you are initiating a connection with your local telephone switch. When you dial a telephone number, your phone switch interprets the digits you dial and determines where to route your call. If your call …
Telephone voltage is actually related to the physical distance at which you can operate the telephone. If the voltage is high, it can signal to great distance. However, higher voltage carries certain risks. 48 V is a compromise between distance and safety. 50-52 V is used in central office common batteries, but designations and documents …
The NAM (Number Assignment Module) is the EPROM (Erasable Programmable Read-Only Memory) in a mobile telephone which holds information such as the MIN (or MDN) and SIDH. The data fields stored in a phone’s NAM vary between the various mobile telephone specifications, such as AMPS/NAMPS, GSM, PCS, CMDA. In modern networks, NAMs can be reprogrammed …
Loop start is a a signaling technique in which a party gets a dial tone by closing (shorting) a DC current loop. In a loop start signaling system, the electrical loop between your telephone and your central office (CO) is normally open. When you pick up the telephone handset, it causes a circuit to be …
Each GSM and UMTS mobile phone has a unique IMEI (International Mobile Equipment Identity) number. An IMEI number facilitates an important function – it easily identifies a mobile phone being used on a GSM (Global System for Mobile Communications) network. The IMEI is a useful tool to stop a stolen phone from accessing a network …
An LEC, or Local Exchange Carrier, is a telephone company that is responsible for managing calls within a specific territory, such as a city or county. The vast majority of the United States is managed by LECs, which differ from IXCs, or Interexchange Carriers. While LECs manage local calls between two parties, IXCs are responsible …
Sometimes called pre paid or prepay cell phone plans, Pay as You Go Cell Phones are usually used in specific types of mobile phone calling plans. Unlike standard mobile phone calling plans that charge a set monthly fee for a specific amount of calls, pay as you go cell phone calling plans only require the …