PASSTHROUGH><td><code>PASSTHROUGH</code></td><td><p>The SNI string presented by the client will be used as the match
criterion in a VirtualService TLS route to determine the
destination service from the service registry.</p></td></tr><tr id=Server-TLSOptions-TLSmode-SIMPLE><td><code>SIMPLE</code></td><td><p>Secure connections with standard TLS semantics.</p></td></tr><tr id=Server-TLSOptions-TLSmode-MUTUAL><td><code>MUTUAL</code></td><td><p>Secure connections to the downstream using mutual TLS by presenting