In many technical fields, resources are shared by more than one units or devices. To give some examples, in a master slave configuration a plurality of masters may share a common slave, a plurality of units may share a common bus, a plurality of processors may share a common memory or pieces of information such as data packets may be transferred over a common data channel. When more than one unit requests to get access to the shared resource at the same time, a conflict exists between the units requesting access since at a given time only one of the units can get access while the other has to be prevented from accessing.
To address this problem, arbitration is used. Arbitration is a process, where a unit is given priority over another unit (or a plurality of other units). Many arbitration techniques with different degrees of fairness for the requesters and different degrees of complexity are known. Arbitration may take for example into account the number of previous requests by a given unit or the identity of the unit (i.e. the identity of the port. Furthermore, fair arbitration techniques may take into consideration that requesters are handled fair and one requester is for example not blocked by another requester. Fair arbitration techniques include for example round robin arbitration (RR), weighted round robin (WRR) or deficit round robin (DRR).