[nos-bbs] linFBB outgoing compressed fwd to JNOS - a discovery
g.ponza at tin.it
Wed Feb 11 05:14:28 EST 2015
> I noticed for multiple messages, the first one linFBB sends as FA proposal,
> then for reasons unknown to me the second (and subsequent?)
> ones are sent as FB, I don't understand why (might not even try to).
There are so many intrigues discovered after reading and re-reading
the original FBB protocol specification and on the field experience
all let to think that the *practical implementation* of the actual
linFBB (and derivatives) differ from that *original* paper.
However I focused on the following statements:
"The submission of an ASCII message will be in the form :
FA P FC1CDC F6ABJ F6AXV 24754_F6FBB 345
The submission of a binary file will be in the form :
FB P FC1CDC F6ABJ F6AXV 24754_F6FBB 345
• The actual message content is transfered in a different format from
the ASCII protocol.
The transfer is done in binary mode. The format used is derived from the
YAPP protocol which is very reliable.
Each message is made up of a header, blocks of data, an end of message
marker and a checksum. This is directly equivalent to the transfer of
one message in the ASCII protocol.
Unlike YAPP transfers, there is no individual packet acknowledgement
during the transmission of messages, the protocol is thus simpler and
and then, a first protocol deviation:
"French regulations require that the title of the message or the file
name are transmitted in readable ASCII and are not compressed".
So, a chance to clear some real doubts may be that of reading
the actual sources and try to understand the 'why'.
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