1 research outputs found
Nonlinear Instabilities in D2TCP-II
In the era of heavy-duty transmission control protocols (TCP), adapted for
extremely hi-bandwidth datacenters, the fundamental question of stable
interaction with either proposed active queue management(AQM) or popularly
discussed Random Early Detection (RED) remains a hotly debated issue. While
there are claims of "oscillation" only dynamical behavior, there are equally
large number of claims which demonstrate the chaotic nature of different
flavors of TCP and their AQM interaction. In this work, we provide a sound and
analytical mathematical model of DTCP/D2TCP and study their interaction with
threshold based packet marking policy. Our work shows that for a simple
scenario this interaction is chaotic in nature and has large variability in
dynamical behavior over orders of magnitude changes in parameter range as
demonstrated by bifurcation diagrams. We conclude with numerical simulation
evidence that chaotic behavior of protocols is inherent in their design which
they inherit from their early vanilla TCP days, and it has serious implications
for data-center throughput, load batching and collapse in Incast kind of
scenario.Comment: Seven Pages, TIME-E conference at Bandung Indonesi