So, my parents livr in an area where the only internet available is satellite. It sucks.
However, they also have satellite TV and can watch that no problem.
What’s the difference? Is it just a scale issue where TV has more money and resources compared to satellite internet companies?
In: Technology
Which satellite Internet do you have? I (and 3 of my neighbours) have StarLink and it’s awesome (compared to 4G or ADSL). 200MBS download speeds, 50 up, ping rates between 20-50 ms.
A few reasons:
Satellite TV only receives a signal, it doesn’t broadcast one back. The LNB in your dish is incapable of sending data back to the satellite. Dishes that can do so are equipped with powerful transmitters that can actually cause damage if you spend enough time between them and the dish.
TV satellites broadcast a single group of signals to their entire service zone. You’re not getting a different signal when you change the channel, you’re just interpreting a different part of it. (Yes, I know technically SD/HD/international channels are pulling from potentially different satellites)
Terrestrial to satellite communications have latency. A lot of latency. A truly awful amount of latency. Ignoring Starlink, which is its own thing, nearly all satellite communications talk to satellites in geostationary orbit. That’s roughly 22k mi/35k km away. Meaning a round trip request to a satellite Internet provider has to travel 22k miles for your request to reach the satellite, 22k miles for the satellite to look up what you requested from a terrestrial node, 22k miles to send that response to the satellite, and 22k miles to send that response back to you. And that’s assuming it gets the right node on the first try, and ignoring processing queues for other users who also have to go through the same process.
All in all, yeah, satellite Internet blows, but it’s mostly due to physics.
Satellite TV is a one-way broadcast. Satellite internet is point-to-point.
Broadcast works by having a single sender that sends the same signal to everyone. It doesn’t matter whether there’s one receiver or two million receivers, you’re all watching the same set of channels and the infrastructure cost and complexity doesn’t change. When your device is “tuning” to to watch particular channel, what it really does is filter out the signal that you’re not watching.
Point-to-point connection need to be scale with the number of users; you’re competing for a limited resource with all the other users.
Secondly, satellite TV is doesn’t care about latency; if you saw a show 5 seconds later than your neighbor who watches the same show using cable, you would never notice it.
Satellite internet is much more latency sensitive. Sending internet signal up the atmosphere and down again takes a much longer time than through copper/fiber optic, even at the speed of electromagnetic radiation (i.e. speed of light).
Think of it like this.
Satellite TV is kind of like radio. You send out a signal that contains information everybody can read. So one connection can reach millions of people. And it only needs one signal and a transmitter.
Satellite internet is kind of like a telephone. information goes both ways and others cannot listen in. So one connection can only reach one other person. Here you need multiple signals and both a transmitter and receiver. Also individual encryption to make sure that only you can read the data.
As the others said TV signal is shared between all subscribers while Internet data is not. While data is sent to one subscriber the frequencies can’t be used to transmit data to other subscribers nearby from the same satellite.
Try Starlink. While it’s not as good as fiber or cable it’s much better than “traditional” geostationary satellite internet. 20-30 times lower latency, no data caps, and higher speed. They figured how to manufacture satellites cheaper (mass production vs a single monster satellite) and launch cheaper (rocket reusability). That allowed them to orbit satellites much lower profitably. That in turn allowed them to point much more beams at subscribers. The whole Starlink constellation has several hundred times more beams than all geostationary satellites. The more beams, the more capacity.
Broadcast is 1 way, 1 message, no need for dedicated channel,
Dude on top of a tower can shout and hundreds can hear him…
Internet is 2 way, and therefor needs a dedicated channel…
Dude at top of tower now has a single wire to each of 100 people…
Now he can only talk 1/200th of the time to deliver the unique message to each person, and its 1/200th because he has to listen for half the time, so its 1/(people*2),
and as you can see adding more people will make it slower.
They transmit via radio. There’s only so many useful radio frequencies, so this bandwidth is limited.
TV is the same signal sent in one direction to everyone. Internet works in 2 directions and so you are dividing the available radio frequencies by each person using it.
There are ways to make this work better, like splitting the radio beams in different directions that work independently but even then you are likely sharing your beam with others. The more sharing, the slower it gets. If you live somewhere with nobody else around then that’s the best scenario. When there are lots of subscribers around, that’s the worst.
Further to this, each satellite is only going to have hardware that can support a certain amount of traffic. A ground based system is going to see regular improvements. But to improve the hardware on the satellites you are going to have to send up rockets.
In lay terms… Imagine that you’re throwing a party. You post this on FB. People see that… done. Now, instead of doing that, imagine having to call (not text) every person you want to invite.
This is the difference. Megaphone to a crowd vs individual conversations.
Latency. It takes a minimum of 2,000 milliseconds (2 seconds for the signal to travel to space and back. Many times the latency is much higher, like 5 seconds or more. When I had Sat, a few times it spiked up to 20 seconds. This takes gaming completely out of the picture. It is really not possible. And other services will time out after a few seconds of delay and fail.
With TV the signal is 95% one way, and the signal is not interactive, so no one notices if the signal is delayed unless it is by hours.
Many companies also block all ports at the Network Operations Center (NOC) before the signal reaches you, which can also interfere with many services.
Lastly, bandwidth. Internet signals take much higher bandwidth than TV signals, and companies never have enough, so they institute data caps. Hughes Net had a 300MB cap per day. It sounds like plenty, but they count every bite, ever show streamed, every picture loaded on every web page, everyone data sync done in the background on your phones, every single piece of data from every Device on your network. It will eat through that Cap before you know it. After the cap, the service barely works, it is around 28.8k dial up, when it works at all.
Avoid Satellite, it is not worth it. It is also expensive to install and has 2 year contract, with a min 400 dollar early termination fee.
For TV, you send one signal over a wide area, and each house then tubes into segments of that signal for each channel.
For internet, the satellites are so far away that there is actual travel time involved both ways, that can be measured in human noticeable terms. On the internet, this travel time is called lag. Many services on the internet need very low lag to work correctly.
Also, the bandwidth, or pipe that information travels to and from is fairly restricted, so you are very limited as to how many people can use it at once for decent speeds. This is why services like starlonk and such are limited to millions of people worldwide even at full rollout.
Note, that’s not tens of millions, or even hundreds. It’s millions.
Maybe in the future it will be viable for more than super basic internet for a few. But that day is not this day.
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