AASTRA 6700i series, 9143, 9480i, 9480i CT SIP Administrator Guide EN - Manual (Page 673)

6-46 41-001343-01 Rev 03, Release 3.2.2
Ignore Out of Sequence Errors
An Administrator can configure the phone via the “sip accept out of order requests” parameter
to ignore CSeq number errors on all SIP dialogs on the phone. When this parameter is enabled,
the phone no longer verifies that the sequence numbers increase for each message within a
dialog, and does not report a "CSeq Out of Order" error if they do not increase.
An Administrator can enable/disable this feature using the configuration files only.
Enabling/Disabling “Out of Order SIP Requests”
Use the following procedure to enable/disable “out of order SIP requests”.
Note: As the default Asterisk configuration does not fully track dialogs
through a reboot, it is recommended that this parameter be enabled when
using the BLF feature with an Asterisk server. If you do not enable this
feature, then rebooting the Asterisk server may cause BLF to stop
working. With this parameter enabled, the BLF key starts working again
when the phone re-subscribes, which by default, are one hour apart.
Configuration Files
For the specific parameter you can set in the configuration files, see Appendix A, the section, “Ignore Out of
Order SIP Requests” on page A-247.