To secure an accessible computer system, the computer system is monitored for connection transactions. An access requestor is denied access to the computer system when the access requestor initiates a number of connection transactions that exceed a configurable threshold number during a first configurable period of time. The monitoring may include detecting connection transactions initiated by the access requestor, counting the number of connection transactions initiated by the access requestor during the first configurable period of time, and comparing the number of connection transactions initiated by the access requester during the first configurable period of time to the configurable threshold number.