Alcatel SPEED TOUCH 710, Руководство пользователя

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Implementation of
VoDSL at your home
Implementation of
VoDSL at the Central
Office
12 Networking - ATM
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3EC 17605 AAAA TCZZA Ed. 02
12.3 The AST710 Voice VC
For Voice over DSL all VoDSL ports are crossconnected to the
Central Office (CO) via a single dedicated VC.
The
AST710 uses ATMAAL2 to encapsulate the digitized voice
packets.
To ensure the quality of service for a phone connection, the VoDSL
VC occupies a (minimum) secured bandwidth space in the DSL
frequency spectrum, and overrules the migration priority of data
packets.
Moreover, the ATM cells containing the voice packets are sent with
a Constant Bit Rate (CBR) over this privileged space, thus ensuring
impeccable voice quality, and solid connectivity.
The VC ends up at the CO where a VoDSL Gateway extracts the
digitalized voice packets from the ATM cells.
The analog baseband information is retrieved from the voice
packets and forwarded towards the classic telephony network.
From that point on, your telephone connection is a true regular
telephone connection.