Improvement of TCP performance on asymmetric channels based on enhancements of compressing TCP/IP header algorithm

Since asymmetric channels will be common in the emerging Internet, the compressing TCP/IP header algorithm in RFC1144 is regarded as a key solution to a low-speed ACK channel. However, this algorithm has a problem in nature, i.e., if one frame containing the ACK is discarded due to frame CRC error, the successive ACKs within the window will be discarded, that results in the throughput degradation of the channel downstream. To solve this problem, we propose two algorithms: (1) introduce a counter to control the transmission of the compressed and uncompressed header; (2) define a new compressed header with uncompressed fields and use a counter to control the transmission of the old and new compressed header alternatively. The simulation results show that the proposed algorithms significantly improve the TCP performance.