ELVIS-PLUS Protocol TLS 1.3 is widely used to protect traffic in the Internet. However, the format of the TLS 1.3 ClientHello, ServerHello, and EncryptedExtensions handshake messages limits the size of extensions to 64 Kbytes. This specification extends TLS 1.3 to allow extensions in ClientHello, ServerHello, and EncryptedExtensions have size larget than 64 Kbytes.