Prestige 642 PPPoE Modem

What is DSL?

DSL (Digital Subscriber Line) technology enhances the data capacity of the existing telephone line running between the local telephone company switching offices and most homes and offices. While the wire itself can handle higher frequencies, the telephone switching equipment is designed to cut off signals above 4,000Hz to filter noise from the voice line. DSL services are either symmetrical (traffic flows at the same speed in both directions) or asymmetrical (the downstream capacity is higher than the upstream capacity).

As the carrying distance increases, data rates decrease. That means that users who are beyond a certain distance from the telephone company’s central office may not be able to obtain the higher speeds for DSL maximum transmission distances. A DSL connection is a point-to-point dedicated circuit, meaning that the link is always up and there is no dialing required.

What is ADSL?

ADSL is an asymmetrical technology, meaning that the downstream data rate is much higher than the upstream data rate. This works well for a typical Internet session in which more information is downloaded, e.g., from Web servers, than is uploaded. ADSL operates in a frequency range that is above the frequency range of voice services, so the two systems can operate over the same cable.

What is DSL?

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