TECHNICAL REFERENCE

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This chapter provides technical information about how your modem transmits data between

users on your LAN and a service provider over the WAN.

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TRANSMISSION ON THE WIDE AREA NETWORK

 

The technology is ATM over DMT ADSL that provides the high-speed transmission between

 

 

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the modem and the service provider. This transmission occurs over a single-pair telephone line.

The following sections describe these technologies.

 

 

 

 

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ADSL

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Asymmetric Digital Subscriber Line (ADSL) is the technology used to transmit data between the modem and service provider at the physical layer. It provides data at asymmetric rates so

Discrete Multitone (DMT) is the line coding used for ADSL. Basically, it divides the bandwidth into subchannels. Some of the subchannels are reserved for analog POTS. The

PRother subchannels are allocated to upstream and downstream traffic. Within the upstream and downstream subchannels, some subchannels are used for management and performance functions.

that downstream traffic from a service provider to you is faster than upstream traffic from you

 

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to the service provider. The downstream transmission rate is up to 7.552 Mbps, while the

upstream rate is up to 928 kbps. Analog POTS can coexist with ADSL on the same line.

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DMT ADSL provides rate-adaptive transmission that allows the service provider to deliver you the best transmission rate determined by distance and line conditions.

Megabit Modem 500L Installation Manual

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