The purpose of this thesis is to build, configure, and test the IP Multimedia Subsystem signaling network used for voice calls of the Voice over LTE on a virtual machine.
In a VoLTE voice call, instead of the LTE core network, signaling messages run over the architecture of the IP multimedia services controlling architecture, through the IMS system. I introduce the network elements and the protocols that such a system uses, then I install and configure the network components one by one, and finally check their correct functioning.
Users can find each other in the system by using these network nodes. Text based signalling messages are transmitted through the network with the help of the so-called Call Session Control Function components. An element of the system, the Home Subscriber Server contains the personal profiles and information of the registered users. An application server also provides multimedia, even third-party developed services.
During the tests, I study how to register an IMS end-user in the operating network, and then study the voice call structure between two registered devices, rather focusing on how text based SIP messages are transmitted to each other by the network elements and how they communicate in this way. Finally, after the implementation of a multimedia voicemail service, I will present and study its proper functioning.