Products are necessary to observe a protocol so that the interrupt-request (IRQ) traces is often shared. The PCI bus contains 4 interrupt strains, INTA# as a result of INTD#, all of which are available to each gadget. Up to 8 PCI gadgets share the same IRQ line (INTINA# by INTINH#) https://nathanlabsadvisory.com/aramco-cyber-security-compliance/