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Cisco ATA 186 and Cisco ATA 188 Analog Telephone Adaptor Administrator’s Guide (SIP)
OL-3410-01
Chapter5 Parameters and Defa ults
Operating Parameters
Note You cannot simultaneously set bits 20 and 21 to 1. Also, if you set both these bits 0, the action parameter
is not included in the REGISTER message, forcing the proxy ser ver to perform the next step in the call
process.
17—SIP only 0/1—Disable/enable call forwarding performed by the CiscoATA. In SIP, call forwarding can be
performed locally by the CiscoATA or it can be performed by the SIP proxy. If this bit is disabled, the
Cisco ATA forwards the entire dial string, including service activation code, to the SIP proxy for
processing.
18—SIP only 0/1—Disable/enable SIP call return performed by the CiscoATA.
19 0/1—Disable/enable the Cisco ATA to send a ringback tone to the caller.
20—SIP only 0/1—Disable/enable SIP to perform action=proxy in a REGISTER message.
21—SIP only 0/1—Disable/enable SIP to perform action=redirect in a REGISTER message.
22—SIP only 0/1—Disable/enable SIP to process a receive d= tag in the VIA header to extract the exernal IP addresses
used by the Network Address Translation (NAT) router.
When the Cisco ATA is operating behind a NAT, the NATIP parameter must be set to the external IP
address of the NAT router. This allows the correct IP address to be placed in the Contact and SDP
headers.
In release 2.14 or later, you may leave the NAT IP address at the default value of "0" or "0.0.0.0" a nd let
the ATA automatically scan the Via header for a "received=" parameter. The parameter, if present, would
indicate that the CiscoATA is operating behind a firewall.
The Cisco ATA proceeds as follows:
1. If the "received=" parameter is in an INVITE response, the current INVITE is canceled and a new
INVITE is sent with the new IP address extracted from the "received=<NAT IP address>" parameter
in the Contact and SDP headers.
In addition, the Cisco ATA will cancel all previous registrations and re-register with the new IP
address in the Contact header. This step is performed only if registration is currently in an idle state.
2. If the "received=" parameter is in a REGISTER response as a result of a REGISTER command, the
Cisco ATA will cancel all previous registrations and re-register with the new IP address extracted
from the "received=<NAT IP address>" parameter in the Contact header.
Note For the CiscoATA to automatically detect its presence behind a NAT, the SIP proxy server
or remote user agent server must include the "received=" parameter in the Via header in the
responses to the Cisco ATA if the proxy detects that the source address and port do not match
those in the Via header.
23 0/1—Disable/enable the end user to specify the default call waiting state for every call. This can be done
on a permanent basis.
24 0/1—Disable/enable the mixing of audio and call waiting tone during a call.
25—SIP only 0/1—Disable/enable DNS lookup of hostname “From ” header hostname for call return.
26 to 31 Reserved.
Table5-4 ConnectMode Parameter Bit Definitions (continued)
Bit Number Definition