Method and Network Nodes for Handling End-to-End Delays for Voice Calls in a Communication Network

The embodiments herein relate to a method, performed by an IMS core network node (140), for handling end-to-end, E2E, delays for voice calls in a communication network (100). The communication network (100) comprises a packet core network node (130), the IMS core network node (140) and a radio network node (110). The radio network node (110) is serving one or more UEs (120). The IMS core network node (140) obtains a Packet Delay Budget, PDB, for the IMS core network node (140). The IMS core network node (140) estimates a packet delay related to a first voice call, wherein the packet delay is caused by the IMS core network. The IMS core network node (140) determines a PDB for a packet core network node (130) related to the first voice call, taking the estimated packet delay caused by the IMS core network into account. The IMS core network node (140) provides, to the packet core network node (130), the determined PDB for the packet core network node (130). The embodiments herein further relate to corresponding methods, performed by the packet core network node (130) and the radio network node (110).