A method including obtaining parameters for a flow from a first network through a second network, the parameters including: a maximum protocol data unit volume PDUVmax in the first network, a maximum flow bit rate MFBR in the second network, a guaranteed flow bit rate GFBR in the second network, and a maximum protocol data unit delay budget in the second network; deriving from the obtained parameters: a maximum delay a packet of the flow experiences in the second network, wherein the maximum delay is a sum of a maximum PDUVmax dependent contribution and a maximum PDUVmax independent contribution, a minimum delay the packet experiences in the second network, wherein the minimum delay is a sum of a minimum PDUVmax dependent contribution and a minimum PDUVmax independent contribution.