Cisco SPA IP Phone Field Reference
Ext Tab
Cisco Small Business SPA300 Series, SPA500 Series, and WIP310 IP Phone Administration Guide 296
B
 
NAT Settings
Network Settings 
Parameter Description
NAT Mapping Enable  To use externally mapped IP addresses and SIP/RTP 
ports in SIP messages, select yes. Otherwise, select 
no.
Defaults to no.
NAT Keep Alive Enable  To send the configured NAT keep alive message 
periodically, select yes. Otherwise, select no.
Defaults to no.
NAT Keep Alive Msg  Enter the keep alive message that should be sent 
periodically to maintain the current NAT mapping. If the 
value is $NOTIFY, a NOTIFY message is sent. If the 
value is $REGISTER, a REGISTER message without 
contact is sent.
Defaults to $NOTIFY.
NAT Keep Alive Dest  Destination that should receive NAT keep alive 
messages. If the value is $PROXY, the messages are 
sent to the current or outbound proxy.
Defaults to $PROXY.
Parameter Description
SIP TOS/DiffServ Value  TOS/DiffServ field value in UDP IP packets carrying a 
SIP message.
Defaults to 0x68.
SIP CoS Value CoS value for SIP messages. 
Defaults to 3.