Dynamic virtual AliEn Grid sites on Nimbus with CernVM

We describe the work on enabling one click deployment of Grid sites of AliEn Grid framework on the Nimbus 'science cloud' at the University of Chicago. The integration of computing resources of the cloud with the resource pool of AliEn Grid is achieved by leveraging two mechanisms: the Nimbus Context Broker developed at Argonne National Laboratory and the University of Chicago, and CernVM – a baseline virtual software appliance for LHC experiments developed at CERN. Two approaches of dynamic virtual AliEn Grid site deployment are presented.