Parallel overhead extracting method and device in optical synchronization digital transmission system

Abstract

The present invention discloses a method of parallel spending pick-up in light synchronization digital transmission system which comprises an arrangement pick-up spending initial position; the counting of row and column according to a frame head of STM-N data frame; according to the pick-up appending initial position, the address formed by counting is judged; if the address belongs to a section spending part, the section spending counting is carried, and a spending byte is read in STM-N data frame and kept in a memorizer; if the address belongs to a payload part, a payload counting is carried and the spending byte is read in the memorizer. Simultaneously, a device parallel spending pick-up in light synchronization digital transmission system is disclosed which comprises an arrangement module, a row and column counting module, a judgment module, a section spending read preserving module, a memorizer and a section spending pick-up module. The present invention provides a parallel spending pick-up proposal which has the advantages of relatively simple circuit structure, high flexibility, small occupy of resources, and high circuit using rate.

Description

technical field [0001] The invention mainly relates to the field of digital communication, in particular to a method and device for extracting parallel overhead in an optical synchronous digital transmission system. Background technique [0002] Optical Synchronous Digital Transmission (SDH, Synchronous Digital Hierarchy) and Synchronous Optical Network (SONET, Synchronous Optical Network) are currently the most widely used networks in optical networks, and their operation, management and maintenance (OAM, Operation, Administration, Maintenance) are all This is achieved by overhead bytes. The SDH data frame structure sets two different overheads, including section overhead (SOH, Section Overhead) for section layer maintenance and path overhead (POH, Path Overhead) for path layer maintenance. The SOH contains certain frame information, information for maintenance and performance monitoring, and other operational functions. SOH can be further divided into regeneration sectio...

AI Technical Summary

Problems solved by technology

For the serial overhead extraction method, in the case of multiple transmission channels, especially when SDH cross-connect chips mostly use 8 channels, 16 channels, or even 128 channels, the method of serial overhead extraction makes the complexity of the circuit interface and the circuit scale appear as follows: Geometry speed increases, so serial overhead extraction methods are no longer suitable for multiplexed chips

[0004] For the parallel overhead extraction method, usually only a small amount of overhead bytes are extracted, such as the VCS9295 chip produced by VITESS Communication Chip Company, mentioned in the chip manual, in the STM-16 / STS-48 Under the working conditions, each channel can extract a group of 48-byte overhead, three groups of 16-byte overhead, and 3 bytes of overhead, a total of 99 overhead bytes, but when performing overhead extraction, two sets of RAM are required (RAM, Radom Access Memory) storage unit, wherein one group of RAM storage units receives the overhead bytes from the current data stream, and another group of RAM storage units sends the overhead bytes received in the previous frame to the overhead extraction interface , which requires 99×2×136, a total of 26928 RAM storage units, which has a great impact on the scale and timing of large-scale cross-chip

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