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This article discusses how congestion control works in a network, focusing on the scenario of two senders, one router, and two receivers. It explains the concept of router capacity and how it affects the receive rate. The article also explores the delay caused by the router and the exponential rise in the curve as the send rate approaches the router's capacity. Additionally, it provides data for exponential curve buffer overflow and examples of TCP congestion control efficiency with different window sizes.
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Congestion Control Thanks to Kai Shen’s Networking Course at the University of Rochester.
Packets Backup In Network Host C Host D Two Senders, One Router, Two Receivers C (or capacity) is maximum transmission rate that router can sustain.
Assume both HostA and HostB send packets at the same rate. As send rate aproaches half the router’s capacity, the receive rate is throttled by the router. The total receive rate can never exceed “C”, so the receive rate for HostC or HostD can never exceed “C/2” The residence time (Service Time plus Wait Time) can be used to compute the delay caused by the router: Residence Time = Service Time / (1 – Utilization) As send rate approaches C/2, the router’s utilization approaches 100%. This creates the exponential rise in the curve above.
Buffer Overflow In Network Host C Host D
TCP Congestion Control Example 2 3 8 9 14 15 1 4 5 6 7 13 10 11 12 16