Towards Realizing the Performance and Availability Benefits of a Global Overlay Network

Hariharan Rahul, Mangesh Kasbekar, Ramesh Sitaraman, Arthur Berger
Seventh Passive and Active Measurement Conference (PAM), Adelaide, Australia, March 2006

Prior analyses of the benefits of routing overlays are based on platforms consisting of nodes located primarily in North America, on the academic Internet, and at the edge of the network. This paper is the first global study of the benefits of overlays on the commercial Internet in terms of round trip latencies and availability, using measurements from diverse ISPs over 1100 locations (77 countries, 630 cities and 6 continents).

Our study shows that while overlays provide some improvements in North America, their benefits are especially significant for paths with Asian endpoints. Regarding practical considerations in constructing overlay routes, we show that an algorithm that randomly chooses a small number of alternate redundant paths achieves an availability of over 99.5%. We also propose and evaluate a simple predictive scheme that achieves almost optimal latency using only 2-3 paths, and show that this is achievable with surprisingly persistent routing choices.

[PDF (117KB)]

Supplement to the conference paper: MIT CSAIL Tech Report 2005-070

Bibtex Entry:

@inproceedings{rahul2006overlays,
   author =       "Hariharan Rahul and Mangesh Kasbekar and Ramesh Sitaraman and Arthur Berger",
   title =        "{Towards Realizing the Performance and Availability Benefits of a Global Overlay Network}",
   booktitle =    {PAM 2006},
   year =         {2006},
   month =        {March},
   address =      {Adelaide, Australia}
}