[Starlink] Starlink Digest, Vol 12, Issue 6

[David Lang]

On Sat, 5 Mar 2022, Ulrich Speidel wrote:

> On 5/03/2022 7:38 pm, Dick Roy wrote:
>> 
>> */[RR] But they are assuming a “single” channel in the time domain.  When 
>> you can take advantage of other dimensions (eg. space) to create more 
>> channels, (aka SDMA) the capacity goes up!/*
>> 
> /*Taken as read - but it's beside the point. Shannon-Hartley allows you to do 
> what was proposed - turning a channel that supplies a small number of users 
> with a lot of capacity each into one that supplies a large number of users 
> with a little capacity each, and of course if you add diversity (space, 
> polarisation, ...) then this applies even more so. But the point is that each 
> communication system is designed around an expectation of how many users will 
> access it, and that you can't simply take an existing technology and somehow 
> assume that it will work with a larger number of users just because it's 
> theoretically possible. Basically, you can't simply throw more dishys at the 
> problem if you need to serve more users.*/

I don't think anyone is suggesting throwing a massive number of dishys at the 
problem, instead I'm saying that one dishy can support a rather larger number of 
people than one household (with appropriate app selection)

Up until about a year ago, the best that I could get at my house was a 8/1 pair 
of bonded DSL lines (supposed to be a 10/2, but reliability). That actually 
supported 3 people watching videos plus a mail server and various downloading 
(and one of the video watching was commonly replaced by video meetings). I did 
try to avoid large downloads during meetings :-)

Currently I have the 8/1 DSL and a 600MB cable (and haven't yet integrated 
starlink), but I don't always notice when the cable goes out right away (without 
doing something extremely bandwidth heavy), although if it drops to 4/.5 (cable 
and one DSL down), it's pretty noticable.

people who are used to multi hundred Mb or Gb lines don't realize that a lot of 
the stuff they use (outside of bulk downloads) isn't really using that much 
bandwidth (insert bufferbloat rant here :-) )

David Lang