Not a scientific paper, more an opinion about the subject. Hopefully of interest<br><br><a href="http://searchcloudprovider.techtarget.com/feature/Differentiating-your-cloud-computing-SLA-Availability-vs-performance">http://searchcloudprovider.techtarget.com/feature/Differentiating-your-cloud-computing-SLA-Availability-vs-performance</a><br clear="all">

<br>-- <br>Augusto Ciuffoletti<br>Dipartimento di Informatica<br>Università di Pisa<br>56100 - Pisa (Italy)