Eli5: How can we beam unlimited HD satellite TV to billions of homes but satellite internet is objectively terrible?

1.46K viewsOtherTechnology

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

39 Answers

Anonymous 0 Comments

Among other issues, it doesn’t make a difference whether you’re broadcasting a channel to one house or billions. You’re just sending out a single signal and houses can choose to tune in or not. For the internet, each house needs to get a different signal.

Anonymous 0 Comments

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Anonymous 0 Comments

Satellite TV is one-way communication. Think like a radio station, they just transmit their music or talk show and everyone can listen. It doesn’t matter how many people are listening, they could have a billion people receiving or zero and they wouldn’t be able to tell the difference.

Satellite internet is two-way communication. Each user is talking back and forth with the satellite and the more users there are the more demand there is on the satellite for communications. There is a limit to how many people it can talk to before the service starts to degrade. Considering satellites are extremely expensive the company that owns them has a strong incentive to allow as many people use the same satellite as possible since that makes more money back on their investment, and as long as the service isn’t completely unusable people will accept it because they have no other options.

Another thing to consider is the lag time inherent to using satellites. The signal needs to go up to the satellite, then back down to the ground. Potentially it even bounces between satellites in orbit. If that introduces a second of delay then you would never know with TV service; your show being a few seconds behind is undetectable. But with two-way communication of the internet service every interaction experiences that lag. Your computer issues a request and then waits, the satellite sends a response and waits for your reply, etc. All that adds up to a significantly worse experience.

Anonymous 0 Comments

In networking jargon we have one-to-many and many-to-many relationships between clients, switches, servers and all of the services that communicate with them. Satellite TV is a one-to-many network, delivering a single service of content to many endpoint clients. Satellite internet is a many-to-many network relationship, delivering and receiving ambiguous content to and from many endpoint clients to and from many servers. The bandwidth and switching speeds required for satellite internet is far and beyond what is required for satellite TV.

Anonymous 0 Comments

Satellite TV is like radio in your car. It’s just one strong signal send from/to antenna and it’s the same everywhere within range.

With internet it must process received / prepare to send multiple signals as fast as it can in the way only one device on one end will be legible to decipher it.

Anonymous 0 Comments

one person yelling through a bullhorn can speak to a hundred people all at the same time. it’s when those hundred people try to have a direct conversation with that person all at the same time things become complicated

Anonymous 0 Comments

You can shout out in a room full of people and all of them can hear you. However, trying to hold an individual, private conversation with each and every person in the room, at the same time, is far, far more complicated.

Broadcasting satellite TV is the same thing–send out a signal, and the same signal can be “heard” by millions of receivers. But in order to have millions of homes sending and receiving *different* data all day long requires a whole lot of computer-processing power and a whole lot of individual signals.

Anonymous 0 Comments

Broadcast technology.

You’re beaming THE SAME DATA to everyone. The TV channels are the same for everyone, they are all shown at the same time, and they all get sent to everyone.

But the Internet has a vast array of data. You can’t predict what people are going to ask for, not everyone wants to watch the same thing at EXACTLY the same time.

So satellite TV (and radio) is rather easy. Just put your programming on and then just blast it at everyone.

But satellite Internet has three problems:

1. You have to work out what everyone wants. They need to be able to tell you that. That’s difficult – they all individually would have to talk to you somehow, either to the satellite or to a groundstation. That’s complex hardware and a lot of people wanting to talk means they only get a brief time each to talk.
2. When you know what they want, broadcasting it to them means they’re sharing the airwaves with an entire continent of other people’s content too. And pretty much nobody wants exactly the same thing at the exact same time. So instantly the speed of the connection is chopped up among all your active customers.
3. The distance between the ground and the satellite introduces latency. There’s little you can do about this. It’s simple physics – the distances involves means that there will always be a delay between you sending a message and someone receiving it. Most satellite internet sucks for gaming, video- and audio-conferencing (telephony) because of this. Everything feels “laggy”. Browsing and streaming are generally okay but real-time protocols can get laggy.

Basically, it’s the difference between you reading out the newspaper over a tannoy (lots of people get the news, but they don’t get much choice about what news they get and when) and people picking up their own newspaper from the stands (where they can choose which newspaper to read, and when to read it).

Anonymous 0 Comments

Satellite TV is like shooting birds with a shotgun. Satellite Internet is like shooting birds with a rifle, but each bullet has a specific bird’s name on it.

Anonymous 0 Comments

Tl;dr, if you’re not on starlink the satellite is really far away, really old, really slow, and the signal is really weak.

Outside of starlink, most internet satellites are in geosynchronous orbit, which means they are around 35,000km above the earths surface. To beam a signal from your parents house, to the satellite, then back to a ground relay station means it needs to travel 70,000km. If we ignore all the processing needed, that’s 250ms of lag right out of the gate.

Now on top of that, the satellite isn’t going to be that computationally powerful. It can only use as much power as it can get from the solar panels, and it’s going to have to use a radiation hardened CPU(, and its power budget is shared with the processor that flys the satellite and the receive/transmit antennas. On top of that it’s not like you can just go replace it with the latest and greatest tech every year, satellites are expensive and it likely needs to be in orbit for 10+ years to be economical.

And to make matters worse, radiation hardened CPUs are slow, like painfully slow. Think mid-90’s palm pilot slow. A first gen iPhone would run rings around them. This painfully slow CPU has to route data from thousands of endpoints back down to the ground relay, which then has to connect it all the internet. And because the satellite is 35,000km up, the signal isn’t that powerful, so it can only send so much data at a time.