The oscillator control

The invention relates to a method for adjusting an oscillator (44), a packet switched network (21) locating between the oscillator and a specified time source (31), which knows a clock time with a specified accuracy. In the method, a clock (42), which is on the same side of the packet switched network (21) as the adjustable oscillator (44), is updated over the packet switched network (21) on the basis of the clock time known to said time source (31). Said clock (42) is used in the adjustment of the oscillator (44) for making the oscillator (44) to oscillate at a desired frequency. The invention also relates to an apparatus and computer software for adjusting the oscillator.