Methods and apparatus for the hardware implementation of virtual concatenation and link capacity adjustment over SONET/SDH frames

摘要

Methods and apparatus for the hardware implementation of virtual concatenation and link capacity adjustment over SONET/SDH frames include providing a state machine on chip with a SONET/SDH mapper and providing means whereby a plurality of members of a VCG can share the same state machine. The apparatus of the invention preferably includes a time wheel for granting access to the single state machine and memory for storing state information for each of the VCG members. According to the presently preferred embodiment, the invention is implemented on chip with an OC-3 Ethernet mapper. Up to eighty-four VCG members share the same state machine and memory is provided on the chip for maintaining the state information for eighty-four VCG members. Fifteen bits are used to store the state information for each VCG member in low order and seventeen bits are used to store the state information for each VCG member in high order. The presently preferred time wheel runs at 20 MHz.