Summary
Asymmetry affects TCP performance
- ACK channel affects forward throughput
Asymmetry comes in various flavors
- Bandwidth asymmetry (technology)
- Latency asymmetry (MAC interactions)
Fortunately, good performance can be obtained using a two-pronged approach
- Reduce frequency of ACKs (AF, ACC)
- Handle infrequent ACKs (SA, AR)
Cross-layer optimizations are A Good Thing!