NITOS Facility is an integrated facility with heterogeneous testbeds that focuses on supporting experimentation-based research in the area of wired and wireless networks. NITOS is remotely accessible and open to the research community 24/7 through the NITOS portal, allowing users from around the globe to take advantage of highly programmable equipment. The testbed is based on open-source software that allows the design and implementation of new algorithms, enabling new functionalities on the existing hardware. Parallel experimentation (slicing) of different users is enabled, through the utilization of the NITOS scheduler software. NITOS has an established user base of over 4000 users in the past years, with over 20 researchers using the infrastructure in a daily basis.