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Comment by wmf | Hacker News Reader

Or the capacity of the network is really low.

According to Wikipedia they have 52 first-generation satellites from the late 90s, and 24 second-generation satellites from around 2010. And if we go by Iridium's lifetime I wouldn't expect the first generation to still be operational.

Compared to Starlink's 2400 currently operational satellites that does seem low. Even compared to Iridium's 75 from the late 2010s, Globalstar's 24 seems small.

It's the kind of 'low bandwidth' you'd see with analog telephone modems. A single JSON request-response over TLS would take many seconds.

Current generation globalstar is about the same speed as first gen iridium, which is around the speed of a 2400 bps dialup modem from the late 1980s.

With the current satellites, yes, if they think they have enough capital (at least many hundreds of millions) to launch a new clean sheet of paper design LEO network using the existing globalstar L/S-band spectrum licenses, they could implement something better.

The value of globalstar is not in the existing satellites and earth stations, which are pretty much trash at this point for any modern use except very low data rate M2M data in certain geographically restricted areas. The value is in the existing LEO network operational licenses.

Yep, similar value is found on other technically inept solutions that are mostly kept around to keep the license to operate active (since some of those require active use to retain them).

The mentioned in the announcement developing a very efficient data codec for text compression, I'd presume something Binary and not over TLS, just raw data packets probably with some encryption

Given that they're transmitting an app form over to Apple's server, they could encode checkboxes with bitmaps and text fields with dictionary LZMA. There probably will be only a few bytes of the actual data per emergency submission + protocol authentication and error correction overhead.

I'm sure the Apple use case is different from a web api, but it was more for illustrative purposes. I imagine most developers know how to wrap data in JSON and how to do a HTTP call over TLS. When using that as a point of reference, having such a transmission take a long time might show how little bandwidth some M2M networks have (or need).

I wouldn't be surprised if the current Globalstar network is so limited it wouldn't even do voice.

They support voice (https://www.globalstar.com/en-us/products/voice-and-data), it's my understanding that it's analog and not digital though, like a really narrowband landline phone call

That makes sense. Satphones are probably using that same super low symbol rate used by M2M.

Slightly apples-to-oranges comparison on the satellite count.

Unlike Globalstar, the Iridium network uses polar orbits which means they're covering a larger area and thus need more satellites to achieve comparable service in the limited latitudes that Globalstar covers.

(that being said, if you're going to be in mountainous terrain, higher latitudes, far from land, etc then Iridium will have better coverage)

>I wouldn't expect the first generation to still be operational

From Wikipedia:

>In 2007, Globalstar launched eight additional first-generation spare satellites into space to help compensate for the premature failure of their in-orbit satellites. Between 2010 and 2013, Globalstar launched 24 second-generation satellites in an effort to restore their system to full service.

So you're totally right.

They say 85% so it must be 17 out of 20, no?

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