Abstract: A method for allocating bandwidth and routing paths for isochronous packets of a data stream in a network of buses including a source bus and one or more remote destination buses interconnected by a switching fabric is described and implemented in a data network. A network management node is assigned from an available network node and weight is allocated to each channel input output, CIO, based on existing path allocations. For a new request, bandwidth allocation for the isochronous packets in the source bus is obtained and the network management node negotiates bandwidth and routing path allocation for the isochronous packets in the switching fabric and remote destination buses. The network management node obtains bandwidth allocation for the isochronous packets on the remote destination bus and selects the optimal routing path in the switching fabric in dependence on the bandwidth requirements of the data stream and assigned weights.