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Cisco SPA IP Phone Field Reference
SIP Tab
Cisco Small Business SPA300 Series, SPA500 Series, and WIP310 IP Phone Administration Guide
265
A
RTCP Tx Interval
Interval for sending out RTCP sender reports on
an active connection. It can range from 0 to 255
seconds. During an active connection, the
SPA9000 can be programmed to send out
compound RTCP packet on the connection. Each
compound RTP packet except the last one
contains a SR (Sender Report) and a SDES
(Source Description). The last RTCP packet
contains an additional BYE packet. Each SR
except the last one contains exactly 1 RR
(Receiver Report); the last SR carries no RR. The
SDES contains CNAME, NAME, and TOOL
identifiers. The CNAME is set to <User
ID>@<Proxy>, NAME is set to <Display Name> (or
Anonymous if user blocks caller ID), and TOOL is
set to the Vendor/Hardware-platform-software-
version (such as Cisco/SPA9000-1.0.31(b)). The
NTP timestamp used in the SR is a snapshot of
the SPA9000 local time, not the time reported by
an NTP server. If the SPA9000 receives a RR from
the peer, it attempts to compute the round trip
delay and show it as the <Call Round Trip Delay>
value (ms) in the Info section of SPA9000 web
page.
Defaults to 0.
Parameter
Description