17 Jun 2012

Paris University and Telecom ParisTech Publish Availability Ranking of World Cloud Computing

Posted by iwgcr

Press Release

Paris, June 18, 2012. The International Working Group on Cloud Computing Resiliency (IWGCR) formed in March 2012 by Telecom ParisTech and Paris 13 University has published on June 18, 2012, the first Availability Ranking of World Cloud Computing (ARWC). Average unavailability of Cloud services is estimated to 10 hours per year or more. Average availability is estimated to 99.9% or less.

Laurent Séguin, Coordinator of IWGCR, says “The Availability Ranking of World Cloud Computing provides an initial estimate of the average availability of of Cloud Computing services.”

Yingjie XU, PhD student at Paris 13 University, adds “The average unavailability of  public Cloud services can be estimated to 7.5 hours per year or more.” Christophe Cérin, Prof. at Paris 13 University, notices that “this estimate could be compared to the 15 minutes of average unavailability of domestic electricity in a city like Paris.”

Maurice Gagnaire, Professor at Telecom ParisTech says “Data collected for Availability Ranking of World Cloud Computing will be used to analyze the risks of Cloud Computing from a resiliency point of view with a scientific approach taking its roots in Telecommunications.”

Christophe Cérin, Prof. at Paris 13 University, concludes “The Availability Ranking of World Cloud Computing – as any ranking – is tightly related to the estimation method which was adopted. Current ranking relies on public Press reports. Cloud incidents which were not reported by Press were not taken into account. The number of users hit by an outage was also not taken into account due to the lack of public data. We encourage reading the report to understand the limitations of the current ranking and how we plan to improve it in the future.”

The report can be downloaded here: Downtime Statistics of Current Cloud Solutions (PDF). Current ranking (2007-2012) is:

Rank  Service Yearly Unavailability (hour) Availability(%)
1 Amadeus  0.167  99.998%
2 Facebook  0.500  99.994%
3 ServerBeach  0.667  99.992%
4 Paypal  0.833  99.990%
5 Google  0.833  99.990%
6 Yahoo!  1.000  99.989%
7 Twitter  1.167  99.987%
8 Amazon  4.000  99.954%
9 Microsoft  5.167  99.941%
10 Hostway  12.000  99.863%
11 BlackBerry  12.000  99.863%
12 NaviSite  28.000  99.680%
13 OVH  28.333  99.677%

Permanent Link


Contact Information

Name: Jean-Paul SMETS (French, English, Spanish, Japanese)
Email: contact@iwgcr.org
Phone: +33 629 02 44 25


The International Working Group on Cloud Computing Resiliency (IWGCR) is a working group with a mission to monitor and analyze Cloud Computing resiliency. The working group is composed of I.T. Executives, academic researchers and industry representatives.

  • Laurent Séguin (VIFIB, France)
  • Prof. Maurice GAGNAIRE (Telecom ParisTech, France)
  • Felipe Diaz (Telecom ParisTech, Colombia)
  • Camille Coti (Galileo Institute, France)
  • Christophe Cérin (Galileo Institute, France)
  • Kazuhiko SHIOZAKI (Nexedi, Japan)
  • Yingjie XU (Nexedi, China)
  • Dr. Pierre DELORT (ANDSI, France)
  • Dr. Jean-Paul SMETS (VIFIB, France)
  • Jonathan LE LOUS (Alter Way, France)
  • Stephen LUBIARZ (Institut Mines-Telecom, France)
  • Pierrick LECLERC (Institut Mines-Telecom, France)