Grandstream UCM series IP PBX offer an extensive set of unified communication features in easy-to-manage IP Telephone System. This Grandstream PBX Dubai is a on premise Telephone system with no licensing fees, upgrade fees or costs per feature. The UCM6100 series is designed for small and medium businesses as it supports up to 500 users and the UCM6510 is ideal for small and medium enterprises as it supports up to 2000 users.