what type of media do you propose to run ISBP over?
Sailor-to-Sailor Relay....
Relay? Sounds like a synchronous protocol, requiring heavy use of
real-time techniques such as semaphores --
http://www.anbg.gov.au/flags/semaphore.html
If it were truly "carrier class" it would have large enough spools
to handle plenty of asynchronous messages --
http://www.anbg.gov.au/flags/signal-flags.html
However, those of us who choose to use asynchronous protocols can
more easily make use of powerful, space saving message compression --
http://www.anbg.gov.au/flags/signal-meaning.html
If there is ever an IETF held at sea, I nominate the flag for
"Y - I am carrying mails" as a conference logo.
Cheers,
James