Subject: Re: Relationship DNS-SD and SLP

From: Stuart Cheshire <[email-masked]>
Date: Tue, 6 Aug 2002 20:06:47 -0700

>> This does not satisfy:
>> 
>> 2.1 Name-to-Address Mapping
>
>Sure it does.  Search for the printer which has the name attribute
>equal to the name of the printer you are seeking.   Get its address.

Only if the application developer can safely assume that every printer 
has a unique name. As long as the name is allowed to be optional (or 
'unknown') the application developer has to think of some other way to 
reliably record the identity of the user's chosen default printer.

>> 2.7 "Name Space Management -or- Name Conflict Detection".
>
>Sure it does.  Search for the printer which has the name X.  If a
>printer replies, do not use the name X.

Are all printers *required* to do this? If not, then an application 
developer can't assume that all printers have unique names, so it's not 
much use.

>> 2.5 User-Friendly Names
>
>No, you can display a user friendly name attribute or even a binary
>image attribute icon, etc. in a human interface.

Sure, anyone *could* do anything, but *do* all printers have friendly 
name attributes and binary image attributes? If I'm trying to write 
printing software that works will all printers (the whole point of open 
standards, after all) what can I rely on to be implemented by *every* 
printer? Anything optional can't be safely assumed, so for practial 
purposes it may as well not be in the spec at all.

Stuart Cheshire <[email-masked]>
 * Wizard Without Portfolio, Apple Computer
 * Chairman, IETF ZEROCONF
 * www.stuartcheshire.org