Английская Википедия:1-Meg Modem

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Шаблон:Short description Шаблон:Use mdy dates The 1-Meg Modem in telecommunications was[1] a DSL modem created by Nortel which conforms to the ADSL Lite standard.[2] The 1-Meg Modem was the first xDSL modem to gain approval and registration under FCC Part 68 Rules.[3]

Technical details

The 1-Meg Modem can be deployed up to Шаблон:Convert from the central office providing a downstream bit rate of 960 kilobits per second (kbit/s) and a maximum upstream rate of 120 kbit/s over 24 gauge wire. The second generation could achieve a transfer rate of 1280 kbit/s downstream and 320 kbit/s upstream.[4] Unlike most ADSL modems which use Asynchronous Transfer Mode (ATM) virtual circuits to carry data, the 1-Meg Modem used Ethernet which makes the product easy for most residential users to install themselves but ill-suited for applications that require quality of service to be enforced. At the telephone company switch the installation was relatively simple when the switch was a Nortel DMS Switch.[5] The customer's line card must be swapped with a line card that supported the 1-Meg Modem, and also a card must be added to the drawer that would manage all data from the 1-Meg Modem cards in the drawer.Шаблон:Citation needed

History

At the time the modem was released on August 8, 1997,[6] telephone companies were fearing competition from cable modems. However, early DSL technology was too costly for wide deployment. By October 1998 Nortel claimed more than $1 billion in sales which, in their words, had "the potential for more than one million end-user lines."[7] The modems were originally tested at Northern Illinois University dormitories and worked well even though the school's wiring was relatively old.[8][9]

References

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External links


Шаблон:Compu-network-stub