l(_dot_)wood(_at_)surrey(_dot_)ac(_dot_)uk wrote:
I'd argue that, in ignoring the ramifications of the
end-to-end principle, the effects of errors, and needing
synchronized clocks, that the Bundle Protocol fundamentally
ignores entropy.
It seems to me that DTN and the Bundle protocol is wrongly
architected. As the Internet is mostly non-disruptive,
disruption tolerating technologies should be used only
in the disruptive part of the Internet.
As the Internet allows for great variations in L2 technologies,
some L2, such as IEEE1394, does have synchronized clock within
a link without ignoring entropy, though it is useless to other
part of the Internet.
And, for the disruptive part of the Internet, at the application
layer, we already have a solution: SMTP, POP, IMAP and MX of DNS.
Don't try to solve an already solved old problem.
Protocols like Bundle may be used by a pair of SMTP relays,
communication between which is very disruptive, as is
stated in rfc821:
SMTP is independent of the particular transmission subsystem and
requires only a reliable ordered data stream channel.
though Bundle, it seems to me, is partly a link and partly
a transport protocol.
Masataka Ohta