Secured KVM switching device with unidirectional communications

A Keyboard Video and Mouse (KVM) communication system, comprising:

• a host emulator (HE) module, configured to:
• (a) receive at least one peripheral device (PD) signal from at least one respective PD, (b) read a first version of Extended Display Identification Data (EDID) information from a first memory of at least one display device, and (c) manipulate the first version of EDID information to produce a second version of the EDID information;
• a first unidirectional optical fiber data connection, adapted to transmit the PD signals and the second version of EDID information to one or more device emulators (DEs), via a single optical fiber communication channel;
• and
• a first manually controlled relay having at least two states;
• wherein the one or more DEs are each associated with at least one corresponding computer, and wherein the one or more DEs are configured to:
• transmit the at least one PD signal to a PD signal interface of the corresponding computer;
• store the second version of EDID information on a second memory device, associated with the relevant DE, based on a first state of the first manually controlled relay;
• and
• enable the corresponding computer to read the stored EDID information via a DDC connection of the corresponding computer, based on a second state of the first manually controlled relay.