A Study for a Geographically Distributed Tier2 over Layer-Two Network

Geographic layer-two links, joint with Cloud technologies and new generation network file systems allow to design a new class of services for distributed infrastructures. In this work, we present the architecture of the prototypal distributed Tier2 created between the two sites INFN-Roma1 and INFN-Napoli. The designed architecture takes advantage of a geographic L2 link used to propagate a GlusterFS file system to create a single storage area. On top of this layer, we created a complete Infrastructure as a Service to manage virtual machine in the two sites. The performed analysis demonstrates that the latency does not affect the stability of the global system. Finally, with a set of use-cases we show the effectiveness of our approach.