On designing of LCAS over VCAT for an EOS chip

Ethernet over SDH/SONET (EOS), which connects different Ethernets through the existing SDH/SONET infrastructure, is a promising data transmission technology in today's networks, for it successfully combines the simplicity and affordability of Ethernet with the resilience and scalability of SDH/SONET. Virtual Concatenation (VCAT) is one of the key technologies in EOS, which provides the capability to transmit and receive over several noncontiguous parallel Virtual Container (VC) fragments as a single flow and drastically improves efficiency of over 33 percent against standard concatenations. Link capacity adjustment scheme (LCAS) over VCAT signaling scheme further enhances VCAT to tune bandwidth dynamically at the requests of network management system without disturbing the existing traffic. In addition, the scheme will automatically decrease the capacity if some member of VCAT experiences a failure in the network, and increase the capacity when the network fault is repaired. In this paper, our design of LCAS over VCAT within an EOS chip is provided, which supports four Virtual Concatenation Groups (VCG) to adjust their bandwidth simultaneously. The block diagrams of the total design for LCAS over VCAT are also provided and several open problems that we encountered during implementation and their corresponding solutions are discussed in focus. Thoroughly functional simulations and FPGA verifications have been done to the design to prove its validity. Finally, we have the design synthesized with Synopsys's Design Compiler, which reveals that the whole design is realizable in ASICs.