GENI, the Global Environment for Networking Innovation, is a distributed virtual laboratory for research in networking and distributed systems, with applications in domain science. The main components of GENI include OpenFlow-enabled software defined networking (SDN) resources deployed on over 40 university campuses across the U.S. These resources include both switches and GENI Racks (SDN capable compute clusters with OpenFlow switches for internal and external communications). GENI Racks are currently installed on dozens of university campuses and within R&E network backbones. Also available is a diverse group of programmable computing and wireless networking resources. Researchers access this collection of resources via the key GENI techniques of deep programmability and slicing. Collectively, these resources and methods enable GENI to support a wide variety of research efforts.