ITU G.992.2

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ADSL standards

ADSL ANSI T1.413-1998 Issue 2

G.DMT ITU G.992.1

G.Lite ITU G.992.2

ADSL2 ITU G.992.3/4 ITU G.992.3/4 Annex J ITU G.992.3/4 Annex L

ADSL2+ ITU G.992.5 ITU G.992.5 Annex L ITU G.992.5 Annex M

In telecommunications, ITU G.992.2 (better known as G.Lite) is an ITU standard for ADSL using discrete multitone modulation.

G.Lite offers a maximum of 1.5 Mbit/s downstream and 512 kbit/s upstream and does not require the use of phone line splitters.

Other voice and data services can affect the performance of G.Lite. For example, basic rate interface (BRI) is an ISDN service that can cause interference called cross talk if it is bundled in the same cable with G.Lite services. Physical line conditions, such as bridge taps and load coils, can also cause severe problems for G.Lite services. A bridge tap is any part of the local loop that is not in the direct transmission path between the CO and the service user. If there are too many bridge taps or if they are too close together, ADSL Lite services cannot function. Load coils are placed on longer phone lines to improve their voice frequency response characteristics. A coil is an inductor that acts like a low pass filter; it doesn't allow high frequencies through. Since ADSL Lite uses higher frequencies, it does not work on lines that have load coils.

[edit] External links

• ITU-T Recommendation G.992.2 : Splitterless asymmetric digital subscriber line (ADSL) transceivers