Page 371 - Asterisk™: The Future of Telephony

rtautoclear (global)
This specifies whether or not Asterisk should auto-expire friends created on the fly
on the same schedule as if they had just registered. If set to yes, when the registra-
tion expires, the friend will vanish from the configuration until requested again. If
set to an integer, friends expire within that number of seconds instead of the normal
registration interval:

rtautoclear=yes|no|seconds
rtcachefriends (global)
If rtcachefriends is turned on, Asterisk will cache friends that come from the re-
altime engine, just as if they had come from iax.conf. This often helps with items
such as message-waiting indications on realtime peers:

rtcachefriends=yes|no
rtignoreregexpire (global)
If rtignoreregexpire is set to yes, and a realtime peer’s registration has expired
(based on its registration interval), then Asterisk will continue to use the IP address
and port stored in the database:
rtignoreregexpire=yes|no
rtupdate (global)
If set to yes Asterisk will update the IP address, origination port, and registration
period of a peer upon registration. Defaults to yes:

rtupdate=yes|no
tos (global)
Asterisk can set the Type of Service (TOS) bits in the IP header to help improve
performance on routers that respect TOS bits in their routing calculations. The
following values are valid: CS0, CS1, CS2, CS3, CS4, CS5, CS6, CS7, AF11, AF12, AF13,
AF21, AF22, AF23, AF31, AF32, AF33, AF41, AF42, AF43, and ef (expedited forwarding).
You may also use a numeric value for the TOS bits.
For more information, see the doc/ip-tos.txt file in the Asterisk source directory.
trunk (channel)
IAX2 trunking enables Asterisk to send media (as mini-frames) from multiple
channels using a single header. The reduction in overhead makes the IAX2 protocol
more efficient when sending multiple streams to the same endpoint (usually an-
other Asterisk server):

trunk=yes|no
trunkfreq (channel)
trunkfreq is used to control how frequently you send trunk messages, in millisec-
onds. Trunk messages are sent in conjunction with the trunk=yes command:

trunkfreq=20

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