> -----Original Message-----
> From: Larry Masinter [SMTP:masinter@parc.xerox.com]
> Sent: Monday, June 23, 1997 5:32 PM
> To: Paul Moore
> Cc: 'Scott Isaacson'; ipp@pwg.org; rturner@sharplabs.com
> Subject: Re: IPP>PRO: sorry, binary is better (?)
>
> > -If the protocol is going to be read by a program then the encodings
> are
> > just 'magic numbers' regardless of text or binary. We could choose
> the
> > number '42' to mean 'copies' or we could choose numbers 'COPIES' to
> mean
> > copies just so long as we (the implementors) all agree.
> >
>
> One of the things that is affected by this choice is the extension
> mechanism. Suppose I want to try out a new feature. I'll do it
> privately, and then I want to register it and make it public. If
> I just pick a number, '43', I'm likely to hit someone else's number.
> So maybe I'll use a number out of the private extension space, e.g.,
> '123451'. But then when I change from 'private extension' to
> 'public', I have to go back and recompile all my test code.
>
> With strings, I can pick a string that isn't used by anyone now,
> and most likely won't have to change it by the time I register it.
>
> This sounds pretty sloppy, but it's mainly what's done now for
> many protocols and it's much more robust than numbers.
>
> The protocol strings aren't human-language, they're just close enough
> to
> language to believe that they're extensible in a more distributed
> fashion.
>
> In addition, the debugging and testing aspects shouldn't be ignored;
> it's useful to be able to write a test program in a scripting language
> or even to telnet to port 80 at a host and just type "GET url
> HTTP/1.0"
> without having to count bytes.
>
> Larry
>
> --
> http://www.parc.xerox.com/masinter