Abstract: A destination server communicates with a computer system using cryptographically protected communications utilizing a first negotiable feature. The destination server detects a triggering event and, in response to the triggering event, causes the cryptographic protected communications with the computer system to change from the first negotiable feature to a second negotiable feature. As a result of stored data indicating that the computer system fails to support the second negotiable feature, the destination server initiates a security measure.

Abstract: A destination server communicates with a computer system using cryptographically protected communications utilizing a first negotiable feature. The destination server detects a triggering event and, in response to the triggering event, causes the cryptographic protected communications with the computer system to change from the first negotiable feature to a second negotiable feature. As a result of stored data indicating that the computer system fails to support the second negotiable feature, the destination server initiates a security measure.

Abstract: A destination server receives an application layer request, including a user-agent and one or more cipher suites, from a user client to initiate a secure communications channel. In response to the request, the destination server obtains from a user-agent database a set of one or more cipher suites that are supported by a user agent corresponding to the user-agent provided by the user client. The destination server uses this set of one or more cipher suites to determine if the user client fails to support any of these cipher suites. If the destination server determines, based on the set of one or more cipher suites, that the user client fails to support any of these cipher suites, the destination server initiates one or more security measures.