Cisco 8800 Series, Manual

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Description Parameter
Configured NAT keep alive message periodically.
Perform one of the following:
• In the phone configuration file with XML(cfg.xml), enter a string in this format:
<NAT_Keep_Alive_Enable_1_ ua="na">Yes</NAT_Keep_Alive_Enable_1_>
• In the phone web page, set to
Yes
to configure periodic NAT keep alive
messages.
The service provider might require the phone to send NAT keep
alive messages to keep the NAT ports open.
Check with your service provider to determine the requirements.
Note
Allowed values: Yes and No.
Default: No
NAT Keep Alive
Enable
(Optional)
Configure NAT mapping with STUN
If the service provider network does not provide a Session Border Controller functionality and if the other
requirements are met, it is possible to use Session Traversal Utilities for NAT (STUN) to discover the NAT
mapping. The STUN protocol allows applications operating behind a network address translator (NAT) to
discover the presence of the network address translator and to obtain the mapped (public) IP address (NAT
addresses) and the port number that the NAT has allocated for the User Datagram Protocol (UDP) connections
to remote hosts. The protocol requires assistance from a third-party network server (STUN server) located on
the opposing (public) side of the NAT, usually the public Internet. This option is considered a last resort and
should be used only if the other methods are not available. To use STUN:
• The router must use asymmetric NAT. See Determine Symmetric or Asymmetric NAT, on page 392 .
• A computer running STUN server software is available on the network. You can also use a public STUN
server or set up your own STUN server.
Before you begin
Access the phone administration web page. See Access the Phone Web Interface, on page 104 .
Procedure
Step 1 Select
Voice
>
SIP
.
Step 2 In the NAT Support Parameters section, set the Handle VIA received , Insert VIA received , Substitute
VIA Addr , Handle VIA rport , Insert VIA rport , and Send Resp To Src Port parameters as described in
the NAT Mapping with Static IP Parameters, on page 388 table.
Step 3
Set the parameters as described in the NAT Mapping with STUN Parameters table.
Step 4
Click the Ext(n) tab.
Step 5 In the NAT Settings section, set the parameters as described in the NAT Mapping from Ext Tab with Static
IP Parameters table.
Cisco IP Phone 8800 Series Multiplatform Phone Administration Guide for Release 11.3(1) and Later
391
Cisco IP Phone Installation
Configure NAT mapping with STUN