Telephony

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  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 …

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  Call Back Security

  Call back security, also known as dial back security, is a security mechanism used to authenticate users over dialup lines. The way call back security works is the dialup user calls into the system and enters his username and password. The system then hangs up on the user and calls the user back at a …

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  110 Block

  A 110 block is a punch-down block used to connect wiring for telephone systems, data network wiring, and other low-voltage wiring applications. It improves on the 66 block by supporting higher frequencies and using space more efficiently. A punch-down tool is used to force solid wire into metal slots on the 110 block. Present residences …

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  Loop

  Loops are a pair of phone numbers, usually consecutive, like 836-9998 and 836-9999. They are used by the phone company for testing. What good do loops do us? Well, they are cool in a few ways. Here is a simple use of loops. Each loop has two ends, a 'high' end, and a 'low' end. …

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  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 …

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