ietf-nntp Response from ARTICLE

[Clive D.W. Feather]

John Line said:
> Since RFC 977's description of 502 is consistently
>       502 access restriction or permission denied
> it does not seem an unreasonable choice,

> The definition
>             5xx - Command unimplemented, or incorrect, or a serious
>                program error occurred.
> hardly supports use of 502 as the response to connection by an unauthorised 
> client,

> Either 502 was simply a mistake when allocating the codes 
> defined in RFC977 and used in early implementations, or it fitted the
> response code scheme as envisaged, but not as actually documented.

I've always understood the encoding scheme as:

   4xx - something's broken right now, try again later
   5xx - you might as well give up; some configuration thing would
         have to change or you'd have to use a different parameter
         for this to work

Thus for mail, recipient unavailable is a 4xx issue while nonexistent
domain is a 5xx one. On this basis, 5xx is the right group for permission
denied.

-- 
Clive D.W. Feather       | Work: <clive at linx.org>   | Tel: +44 1733 705000
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