To reduce PSTN connectivity charges, system administrators might want to route calls to off-net destinations by using the IP network to bring the egress point to the PSTN as close as possible to the called number.

G.SHDSL

Also known as G.991.2, G.SHDSL is an international standard for symmetric DSL developed by the ITU. G.SHDSL provides for sending and receiving high-speed symmetrical data streams over a single pair of copper wires at rates between 192 kbps and 2.31 Mbps. G.SHDSL was developed to incorporate the features of other DSL technologies, such as ADSL and SDSL and will transport T1,E1, ISDN, ATM and IP signals. This is the first DSL technology to be developed from the ground up as an international standard.
G.SHDSL was ratified by the ITU in February 2001.

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