Two-Stage Dialing (Spa3102) - Cisco Small Business SPA2102 Administration Manual

Configuring the PSTN (FXO) Gateway on the SPA3102
How VoIP-To-PSTN Calls Work
Cisco Small Business ATA Administration Guide

Two-Stage Dialing (SPA3102)

In two-stage dialing, the SPA3102 takes the FXO port off-hook but does not
automatically dial any digits after accepting the call. To invoke two-stage dialing,
the VoIP caller should INVITE the PSTN Line without the user-id in the Request-URI
or with a user-id that matches exactly the <
user-id in the Request-URI is treated as a request for one-stage dialing if one-
stage dialing is enabled, or dropped by the SPA3102 (as if no user-id is given) if
one-stage dialing is disabled.
HTTP Digest Authentication can be also used for two-stage dialing, as in one-
stage dialing. If using HTTP Digest Authentication or Authentication is disabled, the
VoIP caller should hear the PSTN dial tone right after the call is answered (by a SIP
200 response).
You also can enable PIN authentication. In this case, the VoIP caller is prompted to
enter a PIN number after the SPA3102 answers the call. The PIN number must end
with a # key. The inter-PIN-digit timeout is 10 seconds (not configurable). Up to
eight VoIP caller PIN numbers can be configured on the SPA3102. A dial plan can
be selected for each PIN number. If the caller enters a wrong PIN or the SPA3102
times out waiting for more PIN digits, the SPA3102 tears down the call
immediately with a BYE request.
The call scenarios may involve the following types of callers:
•
VoIP caller—Someone who calls the ATA device via VoIP to obtain PSTN
service
•
VoIP user—A VoIP caller that has a user account (user-id and password) on the
SPA3102
•
PSTN caller—Someone who calls the ATA device from the PSTN to obtain VoIP
service
VoIP callers can be authenticated by one of the following methods:
•
No Authentication—All callers are accepted for service.
•
PIN—Caller is prompted to enter a PIN right after the call is answered.
•
HTTP digest—SIP INVITE must contain a valid authorization header.
PSTN callers can be authenticated by one of the following methods:
•
No authentication—All callers are accepted for service.
•
PIN—Caller is prompted to enter a PIN right after the call is answered.
User ID
n> of the PSTN Line. A different
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