Instructor: The next wireless connection
we need to discuss is satellite connections.
Satellite internet access is a method
of using communications satellites located in space
to connect a user to the internet.
Now up until recently,
satellite internet was really reserved
for just a few special use cases.
For example, if you happen to live out in the countryside
or in a remote area where you couldn't get cable
or cellular or fiber or copper connections,
well, you might want to look at using satellite internet.
Now the great thing about satellite connectivity
is that you can get it anywhere
because pretty much the entire Earth
can be covered by satellite internet at this point.
As long as you can mount an antenna
and it has a clear line of sight
up to the satellite overhead in space,
you can get internet service.
For home users who live in a remote area
of the United States, for example,
you can use a commercial service like HughesNet,
which puts a small satellite dish on your roof,
much like DirecTV or Dish Network does
for your satellite TV,
and then you can use that
to get some decently high speed internet.
Now this is going to cost you more
than an equivalent home fiber, cable or DSL service, though.
But since you're in a remote area,
satellite might be your only option here.
Now remote users are one area that satellite is used,
but the real place where satellite service
really makes its mark is for mobile users on the go.
If you're somebody who's working out of an RV
or a truck in the middle of the oil fields of Texas,
this might be a great place to use satellite.
Or if you're a business traveler like me,
you can be flying around the world on a commercial airplane
or taking a cruise across the ocean
and still remain connected to the internet the entire time.
For example, a few years ago, I took a cruise,
but I couldn't afford to be offline for 10 days
because I had to ensure I could answer student questions
if they came in.
So while I was on that cruise ship,
I was able to get online for about an hour a day
and answer student questions
before I had breakfast in the morning.
This is because the ship had wifi,
but that wifi was connected to satellite internet.
Now it was a bit expensive to use this, but it worked well
and the speeds were actually pretty darn good
with these newer satellite constellations they're using.
In fact, I was able to stream Netflix and Hulu movies
and television shows and answer student questions
and do all of that with no problem.
It was very much like sitting back at home
and using my cable modem.
Now satellite internet does have some drawbacks though.
First, the speed is not going to be as fast as a fiber modem
or a microwave link or even a cable modem.
Now second, it's pretty expensive
for most satellite internet providers
compared to these other options you have.
And third, there's a good amount of latency
in the internet connection when you're using satellite.
This is because communication satellites for the most part
are using geosynchronous satellites located
about 22,000 miles away from the Earth.
Now what happens is you're going to send the signal up
really, really high and that takes one-eighth of a second
to go all the way up to space.
Then, it takes another eighth of a second to go down
to your internet service provider's ground station.
Then it connects to the internet and gets your data
and it goes back up to the satellite,
another eighth of a second,
and then down to you, another eighth of a second.
So that round trip is going to take about 500 milliseconds
or half a second to complete.
For comparison's sake, my microwave length
only has a latency of about five milliseconds,
100 times faster.
So if you're a big video gamer,
that 500 millisecond latency
will simply kill you time and time again.
Now when it comes to satellite,
things are rapidly changing from 2020 to 2025.
Many companies are racing
into the satellite internet market,
especially in the direct to consumer space.
SpaceX with their Starlink is a major player,
having already launched over 1,700 satellites
and gaining regulatory approval to launch
up to 12,000 satellites in total.
Now Starlink is a low-cost option for many consumers as well
with their monthly service
being only about 100 to $200 per month.
But the best part is they've gotten their latency down
to about 30 to 35 milliseconds.
So how did they do this?
Well, they chose not to use geosynchronous orbits.
You see, when you're in geosynchronous orbit,
you only need about three to six satellites
to fully cover about 90% of the Earth,
which is really good,
but you have to be further out from the Earth
to be able to maintain line of sight with all those areas.
From 22,000 miles away,
you can see about a third of the Earth
with a single satellite.
Now Starlink, on the other hand,
has opted to use low Earth orbits,
which is only about 340 miles from Earth.
This is much, much closer
and this is how the latency is reduced
because it has to travel less distance.
So the trade-off here is they now have a much smaller area
with each individual satellite.
For Starlink, each individual satellite
can only cover an area of about 350 miles on the ground
or around 563 kilometers.
This is why Starlink needs to have a lot of satellites
to fully cover the world and provide service.
And that's why they're launching about one satellite a day
to be able to meet this demand.