Re: [Starlink] dynamically adjusting cake to starlink

[Michael Richardson <mcr@sandelman.ca>]

[-- Attachment #1: Type: text/plain, Size: 2208 bytes --]


Mike Puchol <mike@starlink.sx> wrote:
    > This is correct, with a few twists once you throw in inter-satellite
    > links. In future satellite versions, optical
    > links will allow satellites within the same orbital plane to use each
    > other as relays, thus providing coverage in areas not within a
    > gateway’s coverage.

This would seem to wind up overloading the downlink to the gateway, as well
as causing hard to predict fluctuations in bandwidth.   This is definitely a
complex situation where I can see buffers being added looks like a good
cure-all.

Allowing for direct terminal to terminal traffic would ultimately help
as many of the latency sensitive things like gaming and video calls are often
rather local.

    mcr> (Also, we talk about uplink/downlink from the point of view of the the end
    mcr> user station. But, are there better terms from the satellite's point of
    mcr> view to distinguish traffic to/from the end user?)

    > In general, downlink is anything from satellite to ground, be it
    > satellite -> gateway or satellite -> terminal, and uplink the reverse
    > path. These are the clearest terms to use IMHO. Thus, if satellite to
    > terminal has 75/25 DL/UL duty cycle, the satellite to gateway link will
    > be reversed, with 25/75 DL/UL duty cycle.

Yeah, so in order to speak usefully about some of this stuff, I think we need
to distinguish between traffic going "up" which is going towards the Gateway,
from traffic which might be going "up" from the Gateway (or across from
another satellite).  Some additional terms would help.  I had hoped that
there were some :-)

Do you know how traffic is being steered?  I.e. how does the Gateway say
which terminal traffic is to?  All we know is that tweet "Simpler than IPv6"
Some kind of SDN, but based upon what kind of discriminators?
Are there circuits involved (ala ATM or PPPoE), tags like MPLS or 802.1Q?

--
]               Never tell me the odds!                 | ipv6 mesh networks [
]   Michael Richardson, Sandelman Software Works        |    IoT architect   [
]     mcr@sandelman.ca  http://www.sandelman.ca/        |   ruby on rails    [


[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 487 bytes --]