Bob,
Jon also signed on to "Be strict when sending and tolerant when
receiving" which is the version in RFC 1958 (to which he was
a major contributor, needless to say).
Brian Carpenter
[EMAIL PROTECTED] wrote:
>
> *> From [EMAIL PROTECTED] Sun Oct 31 17:32:53 1999
> *> Date: Sun, 31 Oct 1999 19:32:50 -0600 (CST)
> *> From: Tim Salo <[EMAIL PROTECTED]>
> *> To: [EMAIL PROTECTED]
> *> Subject: "Be liberal..."
> *> Content-Length: 925
> *> X-Lines: 28
> *>
> *> Bob Braden,
> *>
> *> It seems like I should know the answer to this, but...
> *>
> *> In RFC 1122 you quote Jon Postel as saying:
> *>
> *> "Be liberal in what you accept, and
> *> conservative in what you send"
> *>
> *> However, in RFC 791 Jon Postel actually said:
> *>
> *> "In general, an implementation must be conservative
> *> in its sending behavior, and liberal in its receiving behavior."
> *>
> *> I can't find the RFC 1122 quote in RFC 791. The RFC 1122 language is
> *> the form that is usually attributed to Jon Postel, but it appears to me
> *> that this may be either your summary of Jon's words or perhaps quoting
> *> Jon's spoken, rather than written, words.
> *>
> *> Do you have any suggestions about how to best reference "Be liberal..."
> *> I would like to quote a document edited by Jon, (without intending
> *> any disrespect for your editorial abilities and accomplishments...).
> *> Or, are you actually the author of the more concise version of "Be
> *> liberal..."?
> *>
> *> Thanks,
> *>
> *> -tjs
> *>
>
> Tim,
>
> I am taking the liberty of CCing this message to the ietf list, since
> the question has arisen several times recently and maybe I can answer it
> once for all.
>
> First of all, the two quotes above are (intended to be) semantically
> equivalent. Jon was fond of stating the idea, and those involved in
> the ARPAnet and early Internet research were familiar with his
> statements. The two quotes do differ in style; the RFC 1122 quote was
> intended to be closer to what Jon actually SAID, while the RFC 791
> version was couched in more formal written language. At the time RFC
> 1122 was published, I checked out the quote with Jon, and he was happy
> with the shorter form. So either quotation is "authorized".
>
> I have recently seen a version that goes something like, "Be
> conservative in what you do and liberal in what you accept". It seems
> to me this is not semantically equivalent to the quotes above, since it
> apparently extends the principle beyond its specific domain of protocol
> packets into some sort of philosophical doctrine about life and
> people. I believe that Jon would not have sanctioned such a liberal
> interpretation.
>
> Bob Braden
