[LINK] web: The NBN satellite Malcolm Turnbull never wanted prepares for liftoff

[Tom Worthington]

On 30/08/15 11:26, Karl Auer wrote:

> ... Probably because compression costs CPU. Like any communications device,
> a satellite is fastest when it can just ship stuff in and out. If it has
> to process what it ships, it slows down. Also, CPU is energy, and a
> satellite has limited energy. ...

As you say, the satellite has only to relay the data, so I would expect 
compression is done in the ground-stations.

The NBN satellite service has separate options for compression of the 
packet headers and data payload. It is the headers which might be used 
in a satellite for routing, but NBN ISS has compression of headers 
turned ON by default and payload compression OFF. This is the opposite 
of what I would expect.


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