Snort is the most popular Open Source Intrusion Prevention System, (IPS), in the world. Snort IPS uses a set of rules to help identify malicious network activity. It then uses those rules in order to find packets that match their criteria and generates alerts. To stop these packets, Snort can also be deployed inline. Snort can be used inline to stop these packets. Snort is available for both personal and business use. Once Snort rules have been downloaded and configured, they are divided into two sets: the "Community Ruleset", and the "Snort Subscriber Ruleset." Cisco Talos has approved the Snort Subscriber Ruleset. Subscribers to the Snort Subscription Ruleset will be notified in real time when the ruleset is released to Cisco customers.