SPA and Wireless IP Phone Field Reference
SIP Tab
Cisco SPA500 Series and WIP310 IP Phone Administration Guide
193
B
SIP Timer Values (sec)
CTI Enable
The CTI interface allows a third-party application to
control and monitor the state of a phone that has
registered with the SPA9000. With this interface, an
application can control a phone to initiate an outgoing
call or answer an incoming call with a mouse click from
a PC.
Caller ID Header
Provides the option to take the caller ID from PAID-
RPID-FROM, P-ASSERTEDIDENTITY, REMOTE-PARTY-
ID, or FROM header.
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), which can range
from 0 to 64 seconds. Defaults to .5 seconds.
SIP T2
RFC 3261 T2 value (maximum retransmit interval for
non-INVITE requests and INVITE responses), which can
range from 0 to 64 seconds. Defaults to 4 seconds.