ZyXEL Communications 782M User Manual
P782M G.SHDSL Bridge
What is DSL?
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.
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.
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.
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.
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.
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
You are always online.
• Dedicated Bandwidth
Line speed is “symmetric,” i.e., the same bandwidth in both directions.
• Investment Protection
Scalability. Offers a flexible upgrade path. You can choose a higher
access speed yourself - no site visit is necessary.
access speed yourself - no site visit is necessary.
• Low Maintenance
Connectivity requires no complex manual configuration.
• Distance Capabilities
G.SHDSL achieves 20% better loop-reach than older versions of
symmetric DSL. (Loop reach defines speed that can be attained at
various distances).
symmetric DSL. (Loop reach defines speed that can be attained at
various distances).
What is DSL?
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