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Re: Re: Discovery Project: Which Mission Next?





Tim Salo wrote:
> 
> I assume that earth stations could use (existing) 44.xx.xx.xx addresses
> to communicate via satellite without the need for DHCP by using a subnet
> mask of 255.0.0.0.  This would allow any two stations with 44.xx.xx.xx
> addresses to communicate without need to dedicate a subnet (with a longer
> subnet mask) specifically for satellite use.  Of course, earth stations
> using this strategy would need to rationalize their IP routing with other
> uses of 44.xx.xx.xx addresses on other interfaces.  And, never mind that
> this approach conflicts with the conventional use of the 44. net
> (namely, a subnet mask of 255.255.255.0).
> 
> On the other hand, I generally like dynamic IP address assignment.  I
> suspect that DHCP could profitably be hacked to work better in this
> environment.  Without referring to the protocol spec, I think that DHCP
> requires at least two round trip times to assign an address.  It
> would be nice to reduce this to one round trip time for satellites.
> You also might want to convince the ground stations to not request an
> address assignment until after AOS, and then perhaps ask a bit aggressively.
> 
> -tjs


I mentioned this in a recent posting about OUTER SPACE - AMSAT having
44.193.x.x assigned for use. How about using those numbers as the
dynamic IP addresses so as not to cause confusion to the rest of the
44.x.x.x net? Would that work? Could we use a variant of Linux (AMSAT
LINUX?) for this on the bird along with releases for users that could be
tied into local J/TNOS stations? 

If you have NOSINTRO by Ian Wade G3NRW, take a look on page 338 Table
A5-2:International IP Address Coordinators. I don't know if Tom Clark
W3IWI is still a coordinator for the 44.193.x.x batch.

How many users at one time would be trying to use this satellite in a
footprint?  10?  20?  100?


I for one know how things can get around here locally when someone is
testing a new J/TNOS system and don't have everything configured
correctly (I caused some problems a few years ago when I started my
system and told not to put it up till I had it running right..<G> ).

Remember that these comments and ideas are only suggestions and dreaming
on the part of one ham that has learned a whole lot and still has a
WHOLE lot more to go.

James KD4DLA
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