What Is Dsl - ZyXEL Communications Prestige 782M User Manual

DSL (Digital Subscriber Line) technology enhances the data capacity of the existing twisted-pair wire that
runs between the local telephone company switching offices and most homes and offices.
There are actually seven types of DSL service, ranging in speeds from 16 Kbits/sec to 52 Mbits/sec. The
services are either symmetrical (traffic flows at the same speed in both directions), or asymmetrical (the
downstream capacity is higher than the upstream capacity). Asymmetrical services (ADSL) are suitable for
Internet users because more information is usually downloaded than uploaded. For example, a simple button
click in a web browser can start an extended download that includes graphics and text.
As data rates increase, the carrying distance decreases. 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.
A DSL connection is a point-to-point dedicated circuit, meaning that the link is always up and there is no
dialing required.
G.SHDSL
G.SHDSL (Single-pair High-speed Digital Subscriber Line) is a symmetrical, bi-directional DSL service that
operates on one twisted-pair wire and provides data rates up to 2.3 Mbits/sec. The "G." in "G.SHDSL" is
defined by the G.991.2 ITU (International Telecommunication Union) state-of-the-art industry standard.
The Benefits of G.SHDSL:
•
Continuous Connection
•
Dedicated Bandwidth
•
Investment Protection
•
Low Maintenance
•
Distance Capabilities

What is DSL?

You are always online.
Line speed is "symmetric," i.e., the same bandwidth in both directions.
Scalability. Offers a flexible upgrade path. You can choose a higher
access speed yourself - no site visit is necessary.
Connectivity requires no complex manual configuration.
G.SHDSL achieves 20% better loop-reach than older versions of
symmetric DSL. (Loop reach defines speed that can be attained at
various distances).
P782M G.SHDSL Bridge
What is DSL?
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