"One of the more difficult problems is "Do not stick out" ([I-D.ietf-tls-sni-encryption]; Section 3.4): if only sensitive/private services use SNI encryption, then SNI encryption is a signal that a client is going to such a service. For this reason, much recent work has focused on concealing the fact that SNI is being protected. Unfortunately, the result often has undesirable performance consequences, incomplete coverage, or both."
それなあっ