On Tue, April 13, 2010 23:38, W B Hacker wrote:
> In RFC 822 et seq, how do you interpet the 'MUST' with regard to;
>
> "6. SUPPORT SERVICES
>
>
> 6.1 DOMAIN NAME TRANSLATION
>
> 6.1.1 INTRODUCTION
>
> Every host MUST implement a resolver for the Domain Name System
> (DNS), and it MUST implement a mechanism using this DNS
> resolver to convert host names to IP addresses and vice-versa
> [DNS:1, DNS:2].
> "
>
> also summarized in tabular form in 6.1.5
>
> How can it accomplish that both way lookup requirement if there are no
> records
> with which to do so?
It doesn't say a host MUST succeed at resolving, it says it MUST provide a
mechanism by which an attempt at resolving can be made.
That's a very very different thing to what you seem to interpret it to mean.
