Units are needed to abide by a protocol so the interrupt-ask for (IRQ) traces can be shared. The PCI bus consists of four interrupt strains, INTA# by way of INTD#, all of which are offered to every machine. Nearly 8 PCI gadgets share exactly the same IRQ line (INTINA# by https://nathanlabsadvisory.com/achieving-fisma-certification-in-the-usa-ensuring-robust-information-security/