Linksys VOICE SYSTEM SPA 900 SERIES - Manual (Page 122)

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Linksys IP Phone Administrator Guide
Firmware Version 5.1
Chapter 5 Linksys IP Phone Field Reference
SIP Tab
Linksys Key System Parameters
STUN Enable Enables the use of STUN to discover NAT mapping. Select yes or no from the drop-down
menu.
Defaults to no.
STUN Test Enable If the STUN Enable feature is enabled and a valid STUN server is available, the Linksys
IP 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 Linksys IP phone detects symmetric NAT or
a symmetric firewall, NAT mapping is disabled.
Defaults to no.
STUN Server IP address or fully-qualified domain name of the STUN server to contact for NAT
mapping discovery.
EXT IP External IP address to substitute for the actual IP address of the Linksys IP phone in all
outgoing SIP messages. If 0.0.0.0 is specified, no IP address substitution is performed.
If this parameter is specified, the Linksys IP phone assumes this IP address when
generating SIP messages and SDP (if NAT Mapping is enabled for that line). However,
the results of STUN and VIA received parameter processing, if available, supersede this
statically configured value.
Defaults to blank.
EXT RTP Port Min External port mapping number of the RTP Port Min. 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.
Defaults to blank.
NAT Keep Alive Intvl Interval between NAT-mapping keep alive messages.
Defaults to 15.
Field Description
Linksys Key System Enable or disable the Linksys Key System on the IP phone.
Defaults to yes.
Multicast Address The multicast address is used by the SPA9000 to communicate with the Linksys IP IP
phones.
Defaults to 224.168.168.168:6061.
Force LAN Codec The choices are: none, G.711u, or G.711a. Defaults to none.
Field Description