It’s this text: First four bytes of the protocol header MUST be set to 0x00, 0x53, 0x50 and 0x01 respectively. If the protocol header received from the peer differs, the TCP connection MUST be closed immediately. The reality is that the fourth byte, version (8b), is 0 in the current implementation. -- Garrett D'Amore Sent with Airmail On March 4, 2014 at 1:55:35 PM, Martin Sustrik (sustrik@xxxxxxxxxx) wrote: -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On 04/03/14 22:47, Martin Sustrik wrote: >> The other thing is *interface* stability, where interfaces are >> not just API/ABI, but also *protocol* level details. The >> protocol asserts version 0 (despite the RFC indicating version >> 1). > > I'll have a look at that later on. You've probably meant this line in the RFC: "sp-tcp-mapping-01" 01 there is an IETF "Internet Draft" version number, not the version of the protocol. Actaully, it looks like that the RFC doesn't specify what the version number is. It should be adjusted to say that it is zero. Hmm… Martin -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.11 (GNU/Linux) Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/ iQEcBAEBAgAGBQJTFkvWAAoJENTpVjxCNN9Y9q4H/3lRjGZqMcjIYjmOm4Y5/L9i 4WM+HstwmHxcPU12ufpa2ARPwUhWHOFGFfIgl9vKhswwWXp5zhebHLOd+Rtu2TAg zH0/yz8loFeaOlzFkK4cfTJ/vQCx00qPnML3S7ZmTsFCz8aapiW14rJ91G9jirmh xLna0+ngGiSFdMPMqPiHWy8xZhupZfV1Hs/qS3OBait0YJ+QjMVQDoL9icUAeKj+ p+G+zQJ2p4BJSK2zADBd7MZG/uzEoScJvwVDLSNLhA9wD23Jbub/+5Wt3VK4kspK CT5ugc/GDROLJLLvD3rqzI3O7hlhTY+KU1z3d1Kf1tHij7doKVzVWSeNUnaky2s= =S6fz -----END PGP SIGNATURE-----