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Re: issues from the bakeoff
>>>>> "Dan" == Dan Harkins <dharkins@network-alchemy.com> writes:
Dan> - Is it OK to send 3 copies of every single message (which one
Dan> implementation was doing)? Yes.
I don't think so.
The general rule of protocol design and implementation is: be strict
in what you send, lenient in what you receive.
To put that differently: I don't subscribe to the notion that
"everything not prohibited by the spec is permitted". Rather, I
interpret the principle above to say: on the transmit side, everything
not specifically allowed is prohibited. On the receive side,
everything not prohibited that can be handled sensibly without
excessive cost is permitted.
For example, I don't think the TCP spec says that you shouldn't send
each packet twice. Does that mean that an implementation that does
this (absent some specifically configured fault tolerance notion) is a
valid implementation? No way.
Similarly, the IKE spec doesn't specifically prohibit sending 3 copies
of the message because, I submit, no one thought that anyone would be
silly enough to do this, so it wasn't necessary to make a specific
rule "don't do this silly thing". But I would certainly call this
implementation broken.
paul
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