Products are needed to abide by a protocol so which the interrupt-request (IRQ) lines could be shared. The PCI bus incorporates four interrupt strains, INTA# via INTD#, all of which can be obtained to every device. As many as eight PCI gadgets share a similar IRQ line (INTINA# through INTINH#) https://nathanlabsadvisory.com/key-components-of-a-successful-incident-response-strategy/