Virtual PBX systems, cloud PBX systems or hosted PBX systems are business telephone systems that deliver PBX functionality as a service, available over the public switched telephone network (PSTN) or the Internet. Hosted PBXs are typically provided by a telephone company or service provider, using equipment located in the premises of a telephone exchange or the provider's data center. This means the customer does not need to buy or install PBX equipment. Generally the service is provided by a lease agreement and the provider can, in some configurations, use the same switching equipment to service multiple hosted PBX customers.
See Melrose Labs Voice Gateway/CloudPBX
Melrose Labs: We deliver innovative services in cloud communications across mobile, fixed-line, satellite and internet. Through these services, we enable businesses to communicate better with their staff and customers, and by doing so, increase their success.