Setup SSL session resumption
SSL/TLS standards define two methods of session resumption -- state-based and stateless. Stateless mechanism has been introduced in '2008 with RFC 4507 (superceded by RFC 5077) as part of TLS family of protocols.
In both cases you need to assign an instance of TElSessionPool class to ElSSLServer.SessionPool property (the pool is shared across instances of ElSSLServer class). That is enough for state-based session resumption.
To support session resumption in a stateless way you need to set ElSSLServer.Extensions.StatelessTLS property to true.