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    • Forward and Reverse Channels

      Forward and Reverse Channels

      Forward and reverse channels refer to a number of frequencies that are used by a telecommunications broadcast system in order for a telephone tower and a cellular telephone to communicate with each other. A forward channel refers to the frequencies used by a telephone tower to communicate with all nearby cellular phones. Contrastingly, a reverse

    • Loop Start

      Loop Start

      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

    • How to Defeat Caller-ID Blocking

      How to Defeat Caller-ID Blocking

      One trick to defeat Caller-ID blocking is to forward your phone line to a friend who lives in another LATA. When your friend receives the anonymous phone call, have him use *69 Call Return to dial to offending party back. As he is now placing a long distance phone call, the telephone number of the

    • How Do Prepaid Cell Phones Work?

      How Do Prepaid Cell Phones Work?

      A prepaid cell phone is one that allows users to pay in advance for their service without the commitment and penalties of a long term contract. While contract plans are still the most popular form of mobile phone service, prepaid cell phones have become very popular in recent years and have grown in use amidst

    • How Cell Phone Tracking Works

      How Cell Phone Tracking Works

      Before GPS started being deployed in the majority of mobile devices sold on the market, the only method available to track a cell phone was triangulating the cell phone’s position using one of several techniques available to law enforcement and other governmental agencies. Today, most cell phone tracking applications work by accessing the GPS location

    • Cell Phone Cloning

      Cell Phone Cloning

      Cell phone cloning refers to the act of copying the identity of one mobile telephone to another. This is usually done to make fraudulent telephone calls. The bill for the calls go to the legitimate subscriber. This made cloning very popular in areas with large immigrant populations, where the cost to “call home” was very

    • Caller-ID

      Caller-ID

      Calling Number Delivery (CND), better known as Caller ID, is a telephone service intended for residential and small business customers. It allows the called Customer Premises Equipment (CPE) to receive a calling party's directory number and the date and time of the call during the first 4 second silent interval in the ringing cycle. Caller-ID

    • ABCD Tones

      ABCD Tones

      The ABCD tones are additional DTMF tones that may be used in any way the standard (0-9) tones are used. These tones are generated using a Silver Box. Engineers envisioned phones being used to access computers and other devices. This vision led to the addition of the number sign (#, sometimes called ‘octothorpe’ or ‘pound’)

    • TIMSI

      TIMSI

      A TIMSI, or Temporary International Mobile Subscriber Identity, number is a random number that is created from a telecommunications subscriber’s IMSI number in order to provide additional security. While an IMSI is unique to each subscriber and is a permanent number that can be used to track a subscriber or interfere with his/her services, a

    • IVR Software

      IVR Software

      IVR software enables companies to build custom Interactive Voice Response (IVR) systems, which can be used to provide automated self-service to inbound callers. IVR enables callers to interact more intuitively with automated phone systems, while at the same time providing significant cost reductions over human operators. IVR Call Flows A sample IVR call flow might

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