Cisco 7800 Series Administration Manual page 157

Parameter
Send Resp To Src Port
STUN Enable
STUN Test Enable
STUN Server
EXT IP
EXT RTP Port Min
NAT Keep Alive Intvl
Description
Enables to send responses to the request source port instead of the VIA
sent-by port.
Default: No
Enables the use of STUN to discover NAT mapping.
Default: No
If the STUN Enable feature is enabled and a valid STUN server is
available, the phone can perform a NAT-type discovery operation when
it powers on. It contacts the configured STUN server, and the result of
the discovery is reported in a Warning header in all subsequent
REGISTER requests. If the phone detects symmetric NAT or a
symmetric firewall, NAT mapping is disabled.
Default: No
IP address or fully-qualified domain name of the STUN server to contact
for NAT mapping discovery. You can use a public STUN server or set
up your own STUN server.
Default: Blank
External IP address to substitute for the actual IP address of phone in
all outgoing SIP messages. If 0.0.0.0 is specified, no IP address
substitution is performed.
If this parameter is specified, phone assumes this IP address when
generating SIP messages and SDP (if NAT Mapping is enabled for that
line).
Default: Blank
External port mapping number of the RTP Port Minimum number. If
this value is not zero, the RTP port number in all outgoing SIP messages
is substituted for the corresponding port value in the external RTP port
range.
Default: 0
Interval between NAT-mapping keep alive messages.
Default: 15
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