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Linksys ATA Administration Guide
81
Other Options
Configuring the PSTN (FXO) Gateway
Other Options
This section describes other options provided by the Linksys ATA device. It includes the
following topics:
•
”PSTN Call to Ring Line 1” section on page 81
•
”Symmetric RTP” section on page 81
•
”Call Progress Tones” section on page 81
PSTN Call to Ring Line 1
This feature allows a PSTN caller to ring Line 1. When the PSTN line rings, the PSTN Line makes a
local VoIP call to Line 1. If Line 1 is busy, it stops. After a given number of rings, the VoIP gateway
picks up the call.
Symmetric RTP
The
Symmetric RTP
parameter is used to send audio RTP to the source IP and port of the
inbound RTP packets. This facilitates NAT traversal.
The following table lists symmetric RTP parameters.
Call Progress Tones
The ATA has configurable call progress tones. Call progress tones are generated locally on the
ATA, so an end user is advised of status (such as ringback). Parameters for each type of tone (for
instance a dial tone played back to an end user) may include:
•
number of frequency components
•
frequency and amplitude of each component
•
cadence information.
When one VoIP account is shared between the FXS and PSTN Lines, the following parameters
are recommended to be set. See the
Regional
page in the
”Linksys ATA Voice Field Reference,” on
page 94
for these and other call progress tone parameters.
Parameter
Web
Page
Description
Values
Symmetric RTP
Line 1
Enable symmetric RTP operation. If enabled, the Linksys ATA
device sends RTP packets to the source address of the last
received valid inbound RTP packet. If disabled, the Linksys ATA
device sends RTP to the destination as indicated in the inbound
SDP.
Yes or
No
The
default
is
yes
.
Symmetric RTP
PSTN Line
Same as above for the PSTN line.
Yes or
No
The
default
is
yes
.