SNI
acronymcryptographynetworking
Stands for: Server Name Indication
The field in a TLS handshake that names which site the client wants.
Server Name Indication (RFC 6066) lets one IP address host many TLS sites: the client sends the hostname in the ClientHello so the server can present the right certificate. It is sent in the clear in TLS 1.2, which is why Encrypted Client Hello exists.
Also known as: sni