computer network? Well we were discussing VSAT. Then the question came up as if we saw any security issues with satellite based computer networks. Explain.

I'm not sure what issues you are concerned about. Which system-hughes?

I don't know for sure, but I would expect that the communication from the satellite to your computer (actually not your computer, but the receiving equipment that they provide) would be encrypted. After all the if it wasn't not only would there be the security issues, but people could also steal free service with the right equipment and I'm sure they want to prevent that.

First, uplink. Someone would have to be relatively close, but they could intercept your uplink communications (similar to any wireless transmission). With a packet sniffer, they could decode all your transmissions. Once the signal is received by your satellite carrier, anyone with access to its servers (their techs, hackers, etc.) could also access your data. Second, downlink. Since the downlink is going to be VERY broad, just about anyone in the country could intercept the transmission down. You have all the issues with the uplink, but over a much wider area. The solution, like all wireless security solutions, is to encrypt the data, up and down. For some satellite systems, you'll find VPN connections achingly slow.