RE: Slight OT: NASA World Wind project looking for support from network operators.

Since there seems to be a lot of list-related chatter suggesting we use
bittorrent for our distribution needs, I'd like to respond on-list to those.

Why we don't use Bittorrent for distribution of the program:

Actually, theirs no real problem here, we have used bittorrent in the past.
The only real issue is that there are so many non-savvy users, that most of
the users just click past the bittorrent link and go straight for the HTTP

Why we don't use Bittorrent for the distribution of the satellite data:

This is just where P2P and satellite data don't mesh. In order for the
program to work and not be incredibly frustrating and boring, the tiles
(imagery and elevation) have to be loaded at a somewhat speedy rate. Due to
the way P2P has to find and connect to peers before it can start downloading
tiles, it is just too slow for it to work well (and not make everyone
unhappy/ the program useless). The other problem here is that there is
hundreds of gigabytes composing of millions of files, so to be able to get
full coverage of just one dataset would be an enormous effort.

I also received a few responses recommending Coral CDN. Unfortunately for
the program, Coral has a file size limit of 50 MB (Client is currently 188
MB). Unfortunately for the satellite data, since there are so many small
files, it would be quickly pushed out of the cache. Also, coral isn't all
that speedy with responses, so it makes the program moderately sluggish.

Also, while I'm posting, I'd like to ask if anyone has contact information
for someone at, could you please contact me with it? I've been
trying to get in reach with someone over there but all my emails seem to
find a black hole.

Thanks to all.
Matt Mills

hello matt,

i working on another peer tp peer project that was used by the nasa
before you might have a look.



Linux users trying to download updates from their distributors
have similar requirements - though far less of a latency constraint
of course. I wonder if there is a P2P mechanism out there that
would do the right thing for this kind of application.