Running the Italian tier-1 for CMS using Grid tools

The CMS computing system relies on a distributed infrastructure of Grid resources,services and toolkits, whose building blocks are provided by World-wide LHC Computing grid (WLCG). CMs builds application layer able to interface with few at most Grid flavours (LCG2, Grid3,EGEE,Nordugrid,OSG). In the grid-enabled tiered architecture depicted in the CMS computing model, the Tier-1 centers play a crucial role. As an example, recent CMS activities at the INFN Tier1 are birefly outlined and discussed