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RE: Re: Discovery Project: Which Mission Next?

> If there was sufficient processing on board, the ideal 
> situation would be 
> to have the satellite operating as a gateway using DHCP. This 
> would allow 

Well, if the host CPU could run Linux, DHCP would be a breeze. :)  Perhaps
an embedded Linux like platform may work.  There are also reference DHCP
implementations around, so it shouldn't be too difficult to code for another
OS, such as an AMSAT specific one.

> users to be assigned an IP address that is good for the 
> duration of the 
> session or pass. Once the pass is over or the user has logged 
> off (or timed 
> out), the address would be available for a new user. This is how most 

You could simply set a short (20 min) lease tiome for a LEO, and a longer (~
12 hour) for a bird like P3D.  You have to make sure that the available pool
is larger than the maximum number of leases likely to be issued at any given

> dial-up internet accounts work. As for the one-to-many issue, 
> perhaps IP 
> multicast could be used. This should work for transmitting 
> data such as 
> video or bulletins, but I'm not sure how it would work for a 
> round table 
> type discussion.

There are voice multicast apps that will work like this.  Speak Freely is
one open source example (i.e. legally hackable :) ), and probably a good
test bed for multimedia multicast technology.

There is no reason why multicast can't be extended to video.  Again,
examples do exist.  Look up applications written for the MBONE (multicast
backbone).  I suspect there's lots of raw material for IP based multimedia
that could be adapted for satellite use.
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