u03bcs and is divided into a plurality of 64 bit time slots the start of each frame is identified by a so called synchronisation slot s and the end of each frame is provided with so called guard band slots g included to accommodate for small jitters in the network frame frequency the remaining slots of the frame are control and data slots used for transporting control signalling and payload data respectively between the nodes n on the link l write access to the control and data slots are distributed and may at any time be re distributed as desired among the nodes n connected to the link l in the following figures it is assumed that changes in the distribution of write access to slots as well as ownership of time slots is handled by control messages sent and received by the nodes of the network and that said messages include resource transfer res_tr messages ownership change own_ch messages probe pr messages and probe reply pr_rep messages said massages having the following characteristics a resource transfer res_tr is used when a node transfers the write access to a slot to another node it is a unicasted message that is sent from the former node to the latter node and identifies the slot or slots for which write access is transferred an ownership change own_ch message is used by a master node on the link for.