[Starlink] Re: Starlink looking less niche as its retail presence expands

[Michael Richardson <mcr@sandelman.ca>]

{oops, signed message rejected, resending}

As I understand it, the issue is that when a User Terminal changes satellites, it can wind up
going down to a "Landing Ground Station" (GS) different than it had before.
But, due to CGNAT at the GS itself, that packet can not be processed at the
local CGNAT, so it has to travel to the GS that it was allocated for the
CGNAT to work.   (Same thing, alas, with IPv6, which does not have that state!)

While we hope that the terrestrial fiber network is never congested, it does
create some annoying dependancies that are likely to show up when you least
want it.  Like during natural disasters.
Slide 7 thru 12 of Dr.Pan's presentation shows that terrestial network.
Lots of opportunities for jitter, latency, L2 bufferbloat, ...

MobileIP, had it been deployable, could have allowed the GS to send out
messages to corespondant nodes telling them that they should switch their
traffic to the new GS's Home Agent.  IPv6 at least could be less stupid.
Lots of reasons why MobileIP couldn't be done, that Marc alluded to.

Messaging apps that can change their IP will not benefit.
a) the local IP address, 192.168.1.101 hasn't changed.
b) the outside CGNAT address will not have changed, and there is no way
   (AFAIK) for the app to tell the CGNAT at the GS that it would prefer to exit there
   with a different IP.

Maybe I mis-understand what people are talking about.
Video conference calls often last more than the 15min view of a single
satellite.  The situation will be worse initially with OneWeb, as they have
fewer ground stations.