TURN listener port for TLS. Note: actually, "plain" TCP and UDP sessions can connect to the TLS and DTLS port(s), too - if allowed by configuration. The TURN server "automatically" recognizes the type of traffic. Actually, two listening endpoints (the "plain" one and the "tls" one) are equivalent in terms of functionality; but we keep both endpoints to satisfy the RFC 5766 specs. For secure TCP connections, we currently support SSL version 3 and TLS version 1.0, 1.1 and 1.2. For secure UDP connections, we support DTLS version 1.
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