As of LCOS version 8.60 RC2, you can restrict the registration of SIP users at the Voice Call Manager over a WAN link, or prevent this altogether. The configuration for the SIP user now includes a new parameter that controls this. You can allow unrestricted registration over the WAN, via VPN only, or you can prohibit this altogether.
Additional security for the registration is provided by a count of the number of times that a SIP user authenticates incorrectly. Once the counter reaches a threshold value, the device locks the SIP user's account for a certain time. During this period the SIP user cannot log on to the Voice Call Manager. You can freely set the values for the threshold and the duration of the lock.
