[NNTP] Snapshot 6

Russ Allbery rra at stanford.edu
Fri Jan 7 10:02:06 PST 2005


Charles Lindsey <chl at clerew.man.ac.uk> writes:
> Ken Murchison <ken at oceana.com> writes:

>> 3.2.2:

>> Similarly, if we change the IHAVE capability back to TRANSIT, then the
>> STREAMING extension could simply be a STREAMING argument to TRANSIT
>> rather than its own capability.

> Yes, it seems more logical for the capability to be TRANSIT, because
> extensions might offer more transit commands (TAKETHIS, for example).

> Moreover, you MAY provide the IHAVE command even when in READER mode,
> but does this make you a transit/general server (i.e. do you advertise
> the TRANSIT/IHAVE capability)? I would have thought not (certainly not
> TRANSIT) because the exact semantics of IHAVE may be slightly different
> when in READER mode, and you wouldn't expect TAKETHIS suddenly to appear
> as well.

The way I look at this is that really it would be ideal to have every
command have its own capability.  We don't do that for reader commands
because there are too many of them, so we use the READER bundle with some
options instead.  But for transit, there's only one command, so we should
do things in the ideal way.

(It's worth noting that even a mode switching server may provide IHAVE in
reader mode -- but it may be a much less efficient IHAVE than what that
server wants high-traffic peers to use.  I'm not sure how to best capture
this in the language.  I'm not sure that the current MODE READER language
that focuses on whether one wants to use IHAVE is the right concept.
Blah.)

>> 5.2.3:

>> Second example advertises LIST HEADERS but not HDR, as I feared might
>> happen in real implementations.  I'm going to renew my concern over
>> having two capabilities for a single command (HDR & LIST HEADERS,
>> READER & LIST ACTIVE, etc), but I'll defer to the consensus.

> Yes. If we no longer have OVER and HDR as extensions, then we have lost
> the ability to say "If you provide this extension, then you MUST provide
> BOTH of the following commands". I don't think we ever intended to lose
> the ability to say that.

You mean OVER and HDR as capabilities, not extensions, right?

-- 
Russ Allbery (rra at stanford.edu)             <http://www.eyrie.org/~eagle/>



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