Patent ID: 6895023

Claim:
An apparatus for reading data from a packet header of an optical packet transmitted over an optical network, the packet comprising a packet header and a packet payload, the packet header preceding the packet payload, wherein the packet header comprises first and second sections, and wherein the first section comprises a series of clock pulses at the data rate of the second section of the packet header, or a multiple or sub-multiple thereof, the apparatus comprising: an opto-electric conversion circuit for converting the optical packet into an electrical signal; a splitter for splitting or duplicating the electrical signal; a delay element for delaying the first section of the split or duplicated electrical signal to provide timing instants for interpreting the second section; and a decision circuit for interpreting the electrical signal by comparing the signal with a threshold level at timing instants, the decision circuit having a timing input for controlling the timing of the timing instants, wherein the delay element supplies a delayed version of the electrical signal to the timing input of the decision circuit, such that the first section of the header is used to determine the timing instants for interpretation of the second section of the header.