Como funciona el Servicio SSL?

Buenas necesito resolver esta vulnerabilidad pero no tengo claro el concepto del servicio SSL.

Ensure that applications or services are configured to reject SSL version 2 and version 1 communications. Disabling weak cipher methods is a defense-in-depth measure against vulnerabilities that could allow SSL version downgrade attacks (e.g. CVE-2005-2969).

Gracias.