xDSL circuits Becoming more popular than ever, more data and voice
companies are offering Voice over xDSL, which is nothing more than
using a portion of the circuit to transmit and receive voice traffic
between the end user and telco’s PBX system.The Cisco 1750 gateway
www.syngress.com
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is one such device now supporting ADSL for voice, as is the 2600 class
of gateway.
Deciding which technology to use is a matter of having previously decided
upon a voice-capable gateway, getting quotes from your local voice carriers, and
obtaining the cost of installing the appropriate hardware in your gateway. Our
local site decided to use the 2621 gateway with IOS v12.1(8)T, the NM-2V network
module which hosts our two VIC-FXO cards providing a total of four
POTS analog lines to the telco PBX. In this manner, even if our office had to
move, the same gateway can be used at any new site location independent of the
availability of PRI or xDSL circuits.The only drawback was we couldn’t support
more than four active calls simultaneously, regardless whether the calls were
inbound- or outbound-initiated.