From Xojo Documentation
Specifies the available types of SSL connections.
|SSLv23||A TLS/SSL connection established with this value may understand the SSLv3, TLSv1, TLSv1.1 and TLSv1.2 protocols. If extensions are required (for example server name) a client will send out TLSv1 client hello messages including extensions and will indicate that it also understands TLSv1.1, TLSv1.2 and permits a fallback to SSLv3. A server will support SSLv3, TLSv1, TLSv1.1 and TLSv1.2 protocols. This is the best choice when compatibility is a concern.|
|TLSv1||TLS (Transport Layer Security) version 1. (default)|
|TLSv11||TLS (Transport Layer Security) version 1.1|
|TLSv12||TLS (Transport Layer Security) version 1.2|