RootCAs:            config.RootCAs,
			ClientSessionCache: tls.NewLRUClientSessionCache(tlsClientSessionCacheSize),
		})
	} else {
		client = kes.NewClientWithConfig("", &tls.Config{
			MinVersion:         tls.VersionTLS12,
			Certificates:       []tls.Certificate{config.Certificate.Get()},
			RootCAs:            config.RootCAs,
			ClientSessionCache: tls.NewLRUClientSessionCache(tlsClientSessionCacheSize),
		})
	}

	}

	tlsClientConfig := tls.Config{
		RootCAs:            s.RootCAs,
		CipherSuites:       s.CipherSuites,
		CurvePreferences:   s.CurvePreferences,
		ClientSessionCache: tls.NewLRUClientSessionCache(tlsClientSessionCacheSize),
	}

	// For more details about various values used here refer
	// https://golang.org/pkg/net/http/#Transport documentation
	tr := &http.Transport{

		IdleConnTimeout:       timeout,
		TLSHandshakeTimeout:   timeout,
		ExpectContinueTimeout: timeout,
		TLSClientConfig: &tls.Config{
			RootCAs:            globalRootCAs,
			ClientSessionCache: tls.NewLRUClientSessionCache(tlsClientSessionCacheSize),
		},
		DisableCompression: true,
	}
	return updateTransport
}

		PreferServerCipherSuites: true,
		MinVersion:               tls.VersionTLS12,
		NextProtos:               []string{"http/1.1", "h2"},
		GetCertificate:           getCert,
		ClientSessionCache:       tls.NewLRUClientSessionCache(tlsClientSessionCacheSize),
	}

	tlsClientIdentity := env.Get(xtls.EnvIdentityTLSEnabled, "") == config.EnableOn
	if tlsClientIdentity {
		tlsConfig.ClientAuth = tls.RequestClientCert
	}

pkg crypto/tls, const CurveP521 = 25
pkg crypto/tls, const CurveP521 CurveID
pkg crypto/tls, func DialWithDialer(*net.Dialer, string, string, *Config) (*Conn, error)
pkg crypto/tls, func NewLRUClientSessionCache(int) ClientSessionCache
pkg crypto/tls, type ClientSessionCache interface { Get, Put }
pkg crypto/tls, type ClientSessionCache interface, Get(string) (*ClientSessionState, bool)