Radio access networks

A communication system includes remote units, a UTC or GPS reference timing source, and a controller. The controller includes one or more modems and is connected to an external network, at least one of the modems being a baseband modem and being configured to pass first data corresponding to the information. The controller is separated from the remote units by an intermediate network over which second data corresponding to the information is transmitted in frames between the controller and the remote units. The second data includes baseband data. A controller clock is synchronized with the reference timing source and provides timing information to the controller. A remote unit clock is synchronized with the controller clock and provides timing information to a remote unit, the controller and the remote unit being configured to transmit time stamp messages to synchronize the controller clock and the remote unit clock.