sorry, but ...

Tom Thomson colinthomson1 at
Wed Aug 1 11:12:21 BST 2012

Roland Perry wrote
> A message in a bottle is somewhat of a single thing that's sent, whereas
> smoke signals are also communications, and surely must be considered as
> having been sent long before the fire is put out and the final puff of
> smoke emitted? In other words, it's one of those "flows" I keep
> mentioning, where the reception takes place continuously rather than in
> one "lump".

There is a difference between the message having being sent and part of the message having been sent.  Certainly the smoke signal message has not been sent until the last puff of the smoke signal has been emitted.  Of course it is utterly irrelevant whether the fire has been put out or not.   The fire may be used subsequently to send another message, which would be difficult if it had been put out.

Equally a message is received when it is all received.  "Part of the message is received" does not mean 2All of the message is received".

I can encrypt a message by first inverting the order of its bits to achieve an intermediate text, then sticking a nice long salt in front of that string (at least 1.75*network interface unit length bits, and at least as long as the cipher block length and at least as long as the key), then encrypting the result with a decent cipher, lets say AES,  (with block chaining), then inverting the order of the bits in the cyphertext.  If I then transmit the resulting cyphertext, no part of the message can be decrypted until the message has been received; and when the message has been received, all of the message can be decrypted.  I don't think anyone would claim that the meaning of "received" in that sentence is not the normal meaning of the word (which is the meaning I understand words in acts and in regulations made under acts to be required to be interpreted as carrying in cases when no different definition is explicitly provided by legislation) so I don't think it's like that the law will allow you to claim that the message has been received when it has been only partly received.


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