A method for assessing the performance of packet synchronization services in a packet data transmission network. The method includes, at a packet data transmission network probing point, determining at least two synchronization quality describing or influencing parameters based on at least one of a digital timing signal (Sp) received, the recovered time information for at least one timing parameter transmitted into the packet data transmission network, and parameters having impact on the synchronization quality and describing or controlling properties of hardware components present at a receiving network node. The method also includes, at the packet data transmission network probing point, determining a value of at least one synchronization performance score based on the at least two synchronization quality describing or influencing parameters.