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A new functionality that allows sipXecs the to detect DoS attacks and prevent it from crashing the system is available starting with version 4.6. This new Call Rate Limit functionality can be configured from config UI by navigating to System > Call Rate Limit
Call Rate Limit Settings
Packet Rate Counter
The algorithm is a simple packet rate counter that measures the number of packets received per second. A certain threshold can be set via the web UI on what the threshold limit is. The current default is 100 packets per second.
This can be adjusted based on the actual traffic intensity or lack thereof in a particular deployment. A threshold violation triggers an Alarm to be raised so that administrators get a notification when the threshold is reach and if they need to increase it.
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