Any form of encryption on amateur radio frequencies is prohibited under FCC Rules Part §97.113 Prohibited transmissions Section 4 http://www.arrl.org/part-97-te

Any form of encryption on amateur radio frequencies is prohibited under FCC Rules Part §97.113 Prohibited transmissions Section 4 http://www.arrl.org/part-97-text http://www.arrl.org/part-97-text. This makes things like TCP/IP over HAM frequencies legal (as seen here https://en.wikipedia.org/wiki/AMPRNet https://en.wikipedia.org/wiki/AMPRNet) but not SSL traffic. No business transaction required.