[p2p-hackers] p2p in some place or other

[Matthew Kaufman]

Alen Peacock:
>
>   I'd add: what is the self-interested motivation for a node 
> to agree to cache the content in the first place? 

This could be some external motivation like "I want anonymously-posted files
about certain political views to be available for all to see" or "my
corporate IT department says that we have to use this distributed
collaboration tool"

> If proactive caching were turned on by default in my p2p 
> filesharing client, don't I have a very real incentive to 
> turn this off in my own node to preserve bandwidth, disk 
> space, and perhaps limit any legal liability? 

In the general "filesharing" case? Absolutely. But that's not the only use
for P2P technology or even P2P file transfer.

> ...which is similar to many of the arguments made against 
> pre-fetching in traditional caching literature: how do you 
> ensure that you prefetch the right content, especially when 
> the cost of prefetching the wrong content is very high?

Actually, if you're replicating content to other nodes in order to ensure
availability or create more downloadable nodes in order to speed future
downloaders, it is more like the RAID arguments than the cache arguments.

The real question is, IF you had a high-availability file sharing system,
what files would you want to make available on it? (The answer is probably
*not* the long tail of all files ever seen on generic file sharing services)

Matthew Kaufman
matthew at matthew.at
www.amicima.com