I retired in 1998. I then spent 20 years, next March, teaching USAF Computer technicians. The career fields (MOS/Ratings) has changed so much. We used to have separate maintenance crews versus operations; that merged. Crypto became crypto-computer now cyber systems or cyber something (sounds like a Doctor Who episode). We have all kinds of classified networks that use TCP/IP but NOT connected to the Unclassified world.
I was in the Pentagon late 1980s, running the SIOP data center. Had lots of Navy Data Processing ratings and Marines, Army, Air Force working there. Good times, good people, but the Pentagon sure sucked!
Left during Desert Storm and never looked back. Spent 7 years in Europe shutting things down and moving equipment, gear and hard disks for No Such Agency back to Fort Meade for destruction.
Things have changes so much. The Cold War military is as different from today’s as WWII was from the Reagan era.
All encryption at the end points?
None on the long haul trunks?