Depends on the program. I have used several, and I know there are secure telnet programs, although I have not used them.
PuTty comes to mind. In fact, I have suspected that BC was running PuTty on the Blackjack and that is how the remote call was triggered.
Before my back gets overloaded with folks jumping on it, let me say that:
1. It was not found on the BlackJack
2. It is MY OPINION
3. He was seen pressing keys on the HT video
4. There was data useage at the time of the HT trip.
The data usage was during the first HT trip. The call occurred 1 minute before the second trip. So he would have had to set it up with a time delay.