Method and apparatus for correcting a packet delay variation

Abstract

A method and system of correcting a packet delay variation, PDV, of express traffic comprising high-priority express packets interspersed at a transmitter () by a preemption mechanism with a best-effort traffic comprising low-priority best-effort packets, wherein the method comprises the steps of: calculating (S) at the transmitter () a preemption delay value, PRDV, which indicates a preemption delay, PD, introduced by the preemption mechanism; writing (S) the calculated preemption delay value, PRDV, into a delay header field of a header of a high-priority express packet transmitted by said transmitter () via a signal line () to a receiver (); extracting (S) the preemption delay value, PRDV, from the delay header field of the header of the high-priority express packet received by the receiver () via the signal line () from the transmitter (); calculating (S) at the receiver () a variation compensation delay, VCD, value by subtracting the extracted preemption delay value, PRDV, from a predetermined worst-case preemption delay value, PRDV; and applying (S) at the receiver an additional delay to the high-priority express packet according to the calculated variation compensation delay, VCD, value to compensate the preemption delay, PD, introduced by the preemption mechanism at the transmitter ().