A Windows machine loses connectivity for a brief period of time during the network driver installation while the agent installs a network driver to examine traffic. This only happens the first time a policy is applied that includes one of the following:

A Windows machine uses the same driver that is used for all three protection modules. Enabling web reputation, firewall, or intrusion prevention after one of those features has already been enabled will not cause another network blip. You may see a similar interruption in network connectivity when the agent is upgraded (as the driver may also need to be upgraded).