Products are needed to comply with a protocol so that the interrupt-request (IRQ) lines may be shared. The PCI bus involves four interrupt strains, INTA# by INTD#, all of which are offered to every machine. As many as eight PCI equipment share the exact same IRQ line (INTINA# through INTINH#) https://nathanlabsadvisory.com/cisa-certified-information-system-auditor/