Speeding up TCP/IP: Faster Processors are not Enough

Over the last decade we have been witnessing a signi cant increase in the capabilities of our computing and communication systems. On the one hand, processor speeds have been increasing exponentially, doubling every 18 monthsorso,while network bandwidth, has followed a similar (if not higher) rate of improvement, doubling every 9-12 months, or so. Unfortunately, applications that communicate frequently using standard protocols like TCP/IP do not seem to improve at similar rates. In our attempt to understand the magnitude and reasons for this gap between processor speed and interprocess communication performance, we study the execution of TCP/IP on several processors and operating systems that span a time interval of more than eight years. Our main conclusion is that TCP/IP performance does not scale comparably to processor speed, and this poor scalability is magni ed andpropagated to higher-level protocols like HTTP.