4 ms·

You are underestimating the capacity of modern core routers. A single PTX10016 router could route the entire starlink customer base with no over-subscription at

You are underestimating the capacity of modern core routers. A single PTX10016 router could route the entire starlink customer base with no over-subscription at all (230 Tbit/s vs 75 Tbit/s from 50 Mbit/s * 1.5M). Actual estimates of the total capacity of Starlink puts it more in the 20Tbit/s range (and that's without taking into account coverage over less populated areas).

Retric 3y ago
First my 3 Tbit/s estimate was wildly pessimistic and only covered current network utilization. Adding missing countries plus ships more than doubles land area, 42,000 satellites is more than 10x current satellites, v2 is ~10x current individual satellite bandwidth. So current goals are at least 200x current bandwidth. (Satellites also so point to point links which we are ignoring in terms of what the total routing capacity of the network has.) Total estimate for a “fully deployed” Starlink network is therefore 600 Tbit/s from my pessimistic estimate (or half that if your thinking in terms of customer bandwidth vs traffic handled by the network) A more realistic estimate is more like 3,000 TBPs as lower density areas can offer higher bandwidth per customer a village of 100 in the Sahara gets the same bandwidth as a town of 100,000 in the US. How much of that actually gets used is a different story. PS: Individual switches can handle a surprisingly large percentage of total internet bandwidth as packets travel through many of them. 100 switches / average of 4 hops per packet has 25x the bandwidth of a single switch.
- welterde 3y ago
  I was only talking about the currently deployed constellation, which of course is much smaller, but for which we have actual numbers from measurements. For the completed Phase 3 constellation I have read numbers in the range from 1.7 - 2.3 Pbit/s as theoretical maximum. So would need around 8-12 PTX boxes to reach the same total routing capacity as the whole future constellation. The current single-fiber bandwidth record is 1.53 Pbit/s. And nevermind that Starlink will run out of ground station / inter-satellite link capacity long before reaching the theoretical maximum.
  - Retric 3y ago
    Ah, you said planned here so I assumed that was what you where talking about: > The entire _planned_ starlink constellation has less aggregate switching capacity than a pair of current generation core routers. I generally agree with those estimates based on how they’re defining limits though those definitions really depend on what you care about. Aka predicting actual utilization at one end vs just considering what the satellites could physically do in ideal conditions etc. Thus the theoretical impact of direct customer to customer links for a satellite over the Atlantic for example can vary wildly.

Retric 3y ago

First my 3 Tbit/s estimate was wildly pessimistic and only covered current network utilization. Adding missing countries plus ships more than doubles land area, 42,000 satellites is more than 10x current satellites, v2 is ~10x current individual satellite bandwidth. So current goals are at least 200x current bandwidth. (Satellites also so point to point links which we are ignoring in terms of what the total routing capacity of the network has.) Total estimate for a “fully deployed” Starlink network is therefore 600 Tbit/s from my pessimistic estimate (or half that if your thinking in terms of customer bandwidth vs traffic handled by the network) A more realistic estimate is more like 3,000 TBPs as lower density areas can offer higher bandwidth per customer a village of 100 in the Sahara gets the same bandwidth as a town of 100,000 in the US. How much of that actually gets used is a different story. PS: Individual switches can handle a surprisingly large percentage of total internet bandwidth as packets travel through many of them. 100 switches / average of 4 hops per packet has 25x the bandwidth of a single switch.

welterde 3y ago
I was only talking about the currently deployed constellation, which of course is much smaller, but for which we have actual numbers from measurements. For the completed Phase 3 constellation I have read numbers in the range from 1.7 - 2.3 Pbit/s as theoretical maximum. So would need around 8-12 PTX boxes to reach the same total routing capacity as the whole future constellation. The current single-fiber bandwidth record is 1.53 Pbit/s. And nevermind that Starlink will run out of ground station / inter-satellite link capacity long before reaching the theoretical maximum.
- Retric 3y ago
  Ah, you said planned here so I assumed that was what you where talking about: > The entire _planned_ starlink constellation has less aggregate switching capacity than a pair of current generation core routers. I generally agree with those estimates based on how they’re defining limits though those definitions really depend on what you care about. Aka predicting actual utilization at one end vs just considering what the satellites could physically do in ideal conditions etc. Thus the theoretical impact of direct customer to customer links for a satellite over the Atlantic for example can vary wildly.