Products are necessary to adhere to a protocol so the interrupt-ask for (IRQ) lines could be shared. The PCI bus incorporates 4 interrupt lines, INTA# by INTD#, all of which can be obtained to each system. Nearly 8 PCI devices share a similar IRQ line (INTINA# through INTINH#) in APIC-enabled https://nathanlabsadvisory.com/smart-contract-audit-copyright-companies/