In the last few years satellite began to be applied in Internet networking, mainly by medium-big ISPs and we have seen it diffused between users. Sat connections are a very different kind of networking than terrestrial ones, with different timing such as higher RTT (round trip time), but also with different bandwidth value, up to 2 Mbps or more.
How does it work
We can imagine a path like this:
So first we make the request (1) (using our Internet connection) to the Sat-Server, after it will retrieve out info from Internet (2) and it will send it to Satellite (3); in the end we would receive data from the it (4) to our home using a parabolic antenna and a Sat Card.
Typically exist 2 kinds of request :
* Http
* Ftp
Both of them have a little request data and a much bigger answer size, so satellite works very well with it, but with a big time of answer, this is the biggest problem of satellite connection (consider a typical Sat distance, like 36.000 km, so you would have a time access of [ 36000 km / 300.000 km/s = 0.120 s = ] 120 ms you have to add (2 times, cause first ISPs server send it to, then you download it from) to classical Internet time access.
Recently ISP allows their clients to use also other kind of service, like
* Chat
* News
and many others.
There exist also services called "one-way", which consist in mail service , download on-demand (where you make a file reservation to be scheduled at some time) and site download: these services are offline, so you can access to them without modem (or other kind of) connection.
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