Filter
Top Products
Advanced Options for Voice Services
VoIP-to-PSTN and PSTN-to-VoIP Calling
Cisco SPA232D Administration Guide 215
C
VoIP-to-PSTN and PSTN-to-VoIP Calling
The ATA allows calls to be made by using SIP-based Voice-over-IP (VoIP) services
and traditional telephone Public Switched Telephone Network (PSTN) services.
Calls can be placed and received by using an analog phone or fax machine and
Cisco SPA302D Mobility Enhanced Cordless Telephone Handsets.
The ATA maintains the state of each call and makes the proper reaction to user
input events (such as on/off hook or hook flash). Because the ATA uses the Session
Initiation Protocol (SIP), it is compatible with most Internet Telephony Service
Provider (ITSP) offerings.
How VoIP-To-PSTN Calls Work
To obtain PSTN services through the Cisco SPA302D, the VoIP caller establishes a
connection with the PSTN Line by way of a standard SIP INVITE request
addressed to the PSTN Line.
IP
Analogue
Phone
(FXS port)
or
SPA232D typical topology
or
FXS/DECT
LAN
PC
FXO
WAN
Active PSTN
Cisco SPA232D
Internet Service Provider
Internet (ADSL/Cable
Modem)
Cordless
Phone
(DECT)
Fax Machine
(FXS port)