Re:Boeing 787 In Flight Entertainment System Security fun
by fragmede on Wednesday September 06, 2017 @10:42AM
(#15184048)
Optoisolators are a prolific and an extremely cheap electrical component that performs the "air-gap" functionality.
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Re:Boeing 787 In Flight Entertainment System Security fun
by SAI_Peregrinus on Wednesday September 06, 2017 @01:01PM
(#15185204)
Electrical safety airgapping and information security airgapping are different, and entirely unrelated. If data can pass from one side to the other it's not airgapped (from an infosec perspective).
Re:Boeing 787 In Flight Entertainment System Security fun
by bonzini on Wednesday September 06, 2017 @02:59PM
(#15186206)
Fiber needs transmitter and receiver transducers. If each side has only one of those, data can literally flow only in one direction. So it's still infosec-airgapped in the other.
Re:Boeing 787 In Flight Entertainment System Security fun
by SAI_Peregrinus on Thursday September 07, 2017 @02:53PM
(#15194713)
No, data diodes are a different (but related) concept. An airgap implies no information transfer, either in or out. Use an airgap when information leakage must be stopped (as well as remote attacks), use a data diode when information can be released but you need to stop remote attacks.
Fiber optic connections aren't required, anything with separate transmit and receive lines can be turned into a data diode (as long as the protocols used permit it). RS232 null modem cables with the RX lines disconnected are a classic.