handshake
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... Server Identification and Handshake ...
... the importance of using protocol-specific handshakes to determine and
confirm the identity of the server that is eventually reached.
...
... application protocol developers using S-NAPTR should
identify the mechanics of the expected identification handshake when
the client connects to a server found through S-NAPTR ...
... BEEP,
and IMAP define the necessary handshake mechanisms to accomplish this
task. Newly defined application protocols should take this into
...
... The basic mechanism works as follows:
1. During some portion of the protocol handshake, the client sends to
the server the original name of the desired destination ...
... channel.
Note that this document does not define either the handshake
mechanism, the specific credential naming fields, nor the name-
matching semantics ...