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    • 3GP

      3GP

      3GP is the standard used today on the 3G mobile phones. It is distinguished in two different standards; the 3GPP, which is used on GSM-based phones and have the file extension, .3gp. There is also the 3GPP2, which is for CDMA-based phones, and have the file extension .3g2. These two standards are MPEG-4 and H.263

    • Country Direct Numbers

      Country Direct Numbers

      Country Direct numbers are used so that you may connect to an operator from a foreign telephone network, without incurring long distance charges. These numbers may be useful in blue boxing, as many countries still have older switching equipment in use. List of Country Direct Numbers Australia (Telstra) (800)682-2878 Austria (Telecom Austria) (800)624-0043 Belgium (800)472-0032

    • Unlocked Cell Phones

      Unlocked Cell Phones

      To understand what an unlocked cell phone is, it is important to first understand what a locked cell phone is. A locked cell phone is one that can only be used with one cellular service provider. In contrast, an unlocked cell phone can be used with any cellular service provider. When a cell phone is

    • Smartphone

      Smartphone

      A smartphone is a mobile phone with a considerably greater amount of functionality than an ordinary mobile phone or a feature phone. Smartphones can be considered a blend between a mobile phone and a full featured mobile computer, similar to the PDAs (Personal Digital Assistants) of the past, but even more capable. They typically include

    • How to Unlock a BlackBerry

      How to Unlock a BlackBerry

      Many wireless providers across the globe, including AT&T/Cingular, T-Mobile, Vodafone, and Verizon sell Blackberries. When these companies sell a BlackBerry, they do so at a discount in order to attract customers. The providers then make up the lost profits over the lifetime of their contract with the customer. To protect those profits, the wireless providers

    • 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’)

    • SS7 (Signaling System 7)

      SS7 (Signaling System 7)

      SS7 (Signaling System 7) is a standard for control signaling in the PSTN (Public Switched Telephone Network. SS7 signaling is done out-of-band, meaning that SS7 signaling messages are transported over a separate data connection. This represents a significant security improvement over earlier systems which used in-band signaling. The first CCS protocol was the Signaling System

    • Cell Phone Frequencies

      Cell Phone Frequencies

      Cell phone frequencies are the frequency ranges within the Ultra High Frequency (UHF) band that are designated for cell phone use. Bluetooth devices, wireless networks, and television signals also use this frequency band. Although cellular phone systems divide cities and geographic areas into smaller cells of coverage, it allows for a fair amount of frequency

    • IS-54 and IS-136: TDMA

      IS-54 and IS-136: TDMA

      IS-54 and IS-136 are standards for TDMA American Digital Cellular. Mobile Frequency Range Rx: 869-894; Tx: 824-849 Multiple Access Method TDMA/FDM Duplex Method FDD Number of Channels 832 (3 users per channel) Channel Spacing 30Khz Modulation DQPSK Channel Bit Rate 48.6Kb IS-54 and IS-136: TDMA Security IS-54 and IS-136 use the CAVE (Cellular Authentication, Voice

    • CLEC (Competitive Local Exchange Carrier)

      CLEC (Competitive Local Exchange Carrier)

      A CLEC, or Competitive Local Exchange Carrier, is a type of telecommunications provider that was formed after the breakup of AT&T. CLECs are usually smaller telecommunications providers that compete with ILECs, or Incumbent Local Exchange Carriers, which were already in place before AT&T’s separation. While CLECs generally provide the same services as ILECS for less,

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