Re: IM2000 Won't Be Worth It

James Craig Burley <[email protected]> wrote:
> >The no-subscription model of mailing lists is certainly interesting.
> >But what does it achieve that cannot be achieved via NNTP today?
> 
> Isn't NNTP a push protocol, requiring its subscribers to, essentially,
> pay for maintaining incoming messages somehow?

No, it's a hybrid. In fact, it seems to me that NNTP offers every
advantage that IM2000 could possibly offer for mailing lists, and
more, and only uses software and protocols that are already available
today.

Take, for example, "microsoft.com". Instead of running thousands of
mailing lists, they run a news server, "news.microsoft.com". You
simply point your news client at that server and you can see all the
"lists". If you subscribe to any then your news client will keep track
of which messages you have read and which you have not. It is "pull"
system just like IM2000 - you go ask for the messages when you want to
read them.

However, your ISP can also run its own news server, and can replicate
all the articles onto that local server (they can either do this via
the "pull" method described above, or they can ask the origin news
server to "push" articles to them as they are posted). This way
customers of that ISP get faster access to the news articles, and the
load on the origin server is reduced.

You can even get cacheing news servers that will pull the articles
from the origin server and then keep them around so other users of
that cache get them more quickly.

> >Also, how do "subscribers" know when there is new mail to be fetched?
> 
> There are at least three fundamentally different models of list
> handling I can think of that IM2000 cleanly supports:

Yes, but they are all one of two things: the users must poll the
central server to see if there are new messages, or the central server
must keep track of a list of subscribers, in which case most of the
benefits of the "no-subscription" model are gone.

> No, but for lists that would be polled by most subscribers only once
> every few days or so, it can be *very* efficient compared to on-demand
> push-style delivery a la SMTP.

Why? Each message is still being download (at least)
once-per-subscriber, so no bandwidth is saved, and resources are
wasted on "are there any new messages? no. oh." transactions. The SMTP
advantages of having to only send a message once per however many
recipients are subscribed at a single domain are lost (unless we
propose some sort of cacheing mechanism too). Plus if the subscribers
really are only polling once every several days, they're on average a
couple of days behind on the list!

Cheers


Jon