The invention includes a method and apparatus for generating virtual clock signals for differing hierarchies in a communication system conveying data frames of differing hierarchies. Specifically, a method according to one embodiment of the invention includes receiving data frames of a first hierarchy, receiving at least one input clock signal, and generating a virtual clock signal using the at least one input clock signal and a clock enable signal. The clock enable signal is generated using at least one of a data rate ratio and a clock rate ratio. The virtual clock signal is adapted for converting at least a portion of the data frames of the first hierarchy to data frames of a second hierarchy. The frequency of the virtual clock signal is determined by applying the clock enable signal to a common clock signal.