TCP-ENO: Encryption Negotiation Option
RFC 8547

Received changes through RFC Editor sync (created alias RFC 8547, changed abstract to 'Despite growing adoption of TLS, a significant fraction of TCP traffic on the Internet remains unencrypted.  The persistence of unencrypted traffic can be attributed to at least two factors.  First, some legacy protocols lack a signaling mechanism (such as a STARTTLS command) by which to convey support for encryption, thus making incremental deployment impossible.  Second, legacy applications themselves cannot always be upgraded and therefore require a way to implement encryption transparently entirely within the transport layer.  The TCP Encryption Negotiation Option (TCP-ENO) addresses both of these problems through a new TCP option kind providing out-of-band, fully backward-compatible negotiation of encryption.', changed pages to 31, changed standardization level to Experimental, changed state to RFC, added RFC published event at 2019-05-22, changed IESG state to RFC Published)