Interrupt servicing node for servicing interrupt requests on a pended bus. The interrupt servicing node provides interrupt acknowledge messages including destination data specifying a particular interrupting node at times when the interrupt servicing node is ready to service the interrupt request message. The interrupt servicing node includes storage elements for indicating whether an interrupt request is pending from a particular interrupting node. An interrupt request message on the bus includes ID data for identifying a particular interrupting node as the source of an interrupt request.