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Configuring SIP, SPCP, and NAT
Configuring SIP
Cisco SPA500 Series and WIP310 IP Phone Administration Guide
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4
Configuring SIP Timer Values
To configure SIP timer values:
STEP 1
Log in to the web administration interface.
STEP 2
Click Admin Login and advanced.
STEP 3
Click the SIP tab.
STEP 4
Under SIP Timer Values, make the necessary configuration changes to the fields
shown in the following table and click Submit All Changes.
SRTP Method
Selects the method to use for SRTP. Two choices are available:
•
x-sipura—legacy SRPT method
•
s-descriptor—new method compliant with RFC-3711 and
RFC-4568
The default value is "x-sipura.”
NOTE
Not applicable to WIP310.
Hold Target Before
REFER
Controls whether to hold call leg with transfer target before
sending REFER to the transferee when initiating a fully-attended
call transfer (where the transfer target has answered). Default
value is “no,” where the call leg is not held.
NOTE
Not applicable to WIP310.
Parameter
Description
Parameter
Description
SIP T1
RFC 3261 T1 value (RTT estimate). Ranges from 0 to 64 seconds.
Defaults to .5 seconds.
SIP T2
RFC 3261 T2 value, which is the maximum retransmit interval for
non-INVITE requests and INVITE responses. Ranges from 0 to 64
seconds.
Defaults to 4 seconds.