Field
Description
Usage tips
Standard
registration
refresh
strategy
The method used to generate the SIP registration expiry
period (the period within which a SIP endpoint must re-
register to prevent its registration expiring) for standard
registrations.
Maximum
: uses the lesser of the configured
Maximum
refresh value and the value requested in the registration.
Variable
: generates a random value between the
configured
Minimum
refresh value and the lesser of the
configured
Maximum
refresh value and the value
requested in the registration.
The default is
Maximum
.
The
Maximum
setting uses the
requested value providing it is
within the specified maximum and
minimum ranges.
The
Variable
setting calculates a
random refresh period for each
registration (and re-registration)
request in an attempt to continually
spread the load. The VCS never
returns a value higher than what
was requested.
This applies only to endpoints
registered with the VCS. It does not
apply to endpoints whose
registrations are proxied through
the VCS.
Standard
registration
refresh
minimum
The minimum allowed value for a SIP registration refresh
period for standard registrations. Requests for a value
lower than this will result in the registration being rejected
with a 423 Interval Too Brief response. The default is 45
seconds.
See
Registration refresh intervals
[p.82]
Standard
registration
refresh
maximum
The maximum allowed value for a SIP registration refresh
period for standard registrations. Requests for a value
greater than this will result in a lower value being returned
(calculated according to the
Standard registration
refresh strategy
). The default is 60 seconds.
Outbound
registration
refresh
strategy
The method used to generate the SIP registration expiry
period for outbound registrations.
Maximum
: uses the lesser of the configured
Maximum
refresh value and the value requested in the registration.
Variable
: generates a random value between the
configured
Minimum
refresh value and the lesser of the
configured
Maximum
refresh value and the value
requested in the registration.
The default is
Variable
.
These options work in the same
manner as for the
Standard
registration refresh strategy
.
However, outbound registrations
allow a much higher maximum
value than standard registrations.
This is because standard
registrations use the re-registration
mechanism to keep their
connection to the server alive. With
outbound registrations the keep-
alive process is handled by a
separate, less resource-intensive
process, meaning that re-
registrations (which are more
resource-intensive) can be less
frequent.
Outbound
registration
refresh
minimum
The minimum allowed value for a SIP registration refresh
period for outbound registrations. Requests for a value
lower than this will result in the registration being rejected
with a 423 Interval Too Brief response. The default is 600
seconds.
Cisco VCS Administrator Guide (X8.1.1)
Page 86 of 507
Protocols
Configuring SIP