i'm sure eve can give us some even-more-up-to-date references on work
related to the above, right eve? <g> the above does look like
interesting work though; i'll have to spend some time there (when i
have some - time, that is). in fact, i can pretty much guarantee it
is/will be good work since i'm friends with the p.i. from umass (jim
k.) and my first industry job offer was from tasc. :)
> Unfortunately, (naive) ACK definitely won't scale to the 'Net : just
> imagine an efficient hardware multicast to a million nodes, with
> a million point-to-point replies back to the origin! Ack! Ack! No
> kidding. I'd like to see even Apache running on an Alpha try
> to keep up with that :-). Of course, you don't have to be naive:
> you can build a tree fanout, and acks don't go back to the root.
> Still, ACK is generally seen as less scalable than NAK.
actually, this is what ibm's cryptolopes claim to provide - exactly a
p-2-p ack for arbitrary content much like the acks you get with
smtp-derivatives nowadays on wintel boxes (and the next five years
ago). interestingly enough, the privacy issues are what folks and
corporations are screaming about, not the network load-related ones.
> So, unrel mcast could conceivably scale pretty high, I guess, and
> even NAK based rels could too. (I'm just guessing here, of course).
> But I doubt ACKs could go to the limit.
what about some kind of collated, inverse-multicast acks? is there
such a thing?
> Another question that would need answers wrt mcasts is mcast
> over wireless IP networks - of particular interest to munchkin fans I think.
> Does anyone know of wireless mcast work? Unlike Ethernet,
> where's the 'shared bus' to deliver packets for free? Perhaps
> all participating mcast nodes tune into the same wireless frequency,
> not unlike how radio and TV broadcasts work. But I thought wireless
> data networks are much lower power, and need very local transmisison
> stations - kind of like current gen. cellular networks. Then a real
> wide area mcast still needs to do a lot of p-to-p propagation to all
> the transmitters, no? Hey - maybe put all of them on a common Ethernet
> structure? Hell, I'm clueless here. Does anyone know??
> Dan at Teledesic maybe?
or perhaps the karma-kids?
---removed dan's excellent and well-balanced comments---
Mark Baker writes:
> On Wed, 11 Jun 1997, Dan Kohn wrote:
> > Remember, as Deering says, that unicast communication is merely a
> > special case of multicast.
>
> Moreover, unicast to an object is a special case of multicast to an
> object group, even with response semantics - be they reliable mcast ACKs
> or responses from an RPC to that group (ala VS).
>
> Put *that* in your pipe and smoke it you "document caching solves all
> my problems" web-heads! 8-)
puff puff...cough cough.
> Mark "recently confirmed at the Church of Objectology" Baker
joe