A Novel Interrupt Method for OTN Defect Transport

There are lots of alarms in an OTN network equipment which need to be processed by a reliable and fast way. After comparing several fault defect circuits, and analyzing the disadvantage of software polling method, a novel interrupt method for OTN defect transport is proposed. The interrupt method is based on a Handshaking mechanism between hardware and software, and the RAM fault defect circuit is used. The Method is described and analyzed in detail especially in reliability and processing time, which is also verified by simulation. As the results show, processing time can be less than 100 us, and omission or mistake for alarm events report can be reduced sharply. This method can successfully deal with collection of lots of alarm in OTN. It has been implemented in FPGA and applied in several OTN products.