This paper studies the problem of TCP in-cast in 802.1Qau network environment. This paper reveals that,

  • TCP with RTO shortened (~10ms) can improve in-cast
  • QCN cannot solve in-cast. Sometimes it worsens the scenario
  • If QCN do sampling more frequent (e.g. sample every packet), the in-cast problem is mitigated
  • When timeout occurs, it would be good if the rate increment in AI phase is smaller, so that when RTO expires, there would not be a big burst

The paper then implements such modification in ns2 and shows the improvement.

Bibliographic data

   title = "Performance of Quantized Congestion Notification in TCP Incast Scenarios of Data Centers",
   author = "Prajjwal Devkota and A. L. Narasimha Reddy",
   booktitle = "Proc. MASCOTS",
   year = "2010",