Legacy Comms

Legacy protocols are still in use by many airlines around the world. Even though most airlines have decided to move to TCP/IP, there is still the die-hards that cling onto to ‘green screen technology’ with the supporting legacy technology underpinning it.
Some of the protocols are still embedded in the industry, so don’t be surprised if you come across them still….

Type A:

X.25:

X.28:

SDLC: