On the present time, the most used technology of core networks is Wavelength-division multiplexing (WDM) which save a lot of bandwidth of optical fiber. But in each node all optical signals must be converted into the electrical domain, processed and converted back into the optical domain. Result of all these steps is that the data spend in the node a lot of time. This time decreases total available bandwidth in the optical networks. One of the results is that we compose WDM nodes which represent hybrid system of switching and controlling. If we use out-of-band signalizing it is simpler to separate control head from the data. For effective control and transmission of data over the optical networks, the reservation protocols are needed in WDM/OBS4,5. In today’s networks exist a lot of the protocols, which have their own advantages and disadvantages. For our investigation it was chosen the reservation protocol called Search & Compare (S &C)1, because it uses parallel-segment based and parallel link reservation. The structure of data will be designed from the point of view of wavelength for transmission channels, length of optical burst, source and group addresses in the segment, number of nodes and the total time needed for switching. Structure of the protocol will contain all of the control messages which are necessary for reservation a path along all segments. The design of the protocol follows the ITU-T recommendation2,3.