[Ham-Computers] Some probably dumb questions

[Paul R]

Hello Ham Computer Gurus (from Melbourne Australia)

I am considering setting up a remote station hf ham radio station and I am 
looking for some advice.

In particular:

I am looking to control my radio via the internet. I am concerned about 
hackers however and enquire as to a decent firewall which could possibly 
password protect the remote computer without disturbing audio streaming etc.

Alternately, is it possible to establish a connection to the remote 
computer using a phone line and say 2 adsl modems at each end.

In other words have a high speed connection between 2 computers linked via 
a phone line only with no internet connection??

My motivation to do this would be security (ie it is a closed system) and 
reduced expense (ie don't require high speed internet connection at each end).

Finally (and not quite computer related) what would be the best way to 
power up and power off the equipment ( I understand there is some way to do 
this via telephone - can you point me to some relevant web pages).

Any pointers you can give would be appreciated

Paul