CRT-Based AL-FEC and Its Application on Streaming over the WiMAX Networks for High-Speed Rail Reception

In recent years, Application-Layer Forward Error Correction (AL-FEC), especially rateless AL-FEC, receives a lot of attention due to its superior performance in both transmission and computation efficiency. Rateless AL-FEC (e.g., Raptor code or LT code) can protect large data block with the overhead somewhat close to ideal codes. In the meantime, its data processing rates of both encoding and decoding are quite efficient even in software implementations (probably reaching Gbps throughput on a modern PC). Due to its properties, rateless AL-FEC is suggested to be used to protect packet erasure for wireless communications or the environments where retransmissions are infeasible. However, we found that conventional rateless AL-FEC may not be the best candidate when considering streaming over WiMAX networks for high speed rail reception in Taiwan. To facilitate streaming service delivery for high-speed rail reception, we proposed a new AL-FEC scheme based on Chinese Remainder Theorem (CRT). The scheme supports greater symbol size than conventional ideal codes and requires less overhead than conventional rateless codes, making the proposed AL-FEC scheme more feasible to harsh bandwidth-limited networks.