Abstract: | With a large number of different heterogeneous network technologies (e.g. UMTS, WLAN, HIPERLAN) and operators expected in the future mobile communications environment, that should frequently and seamlessly interwork with each other and a constantly increasing population of communication parties, capturing the full benefits of open channel key transfers and scaling public key methods requires Public Key Infrastructure (PKI). In this paper, we discuss and investigate different ways to take advantage of a proposed PKI system. Focusing on UMTS Release 6 IP multimedia subsystem, we analyze the ongoing 3GPP specifications and its limitations and examine how PKI can provide robust security solutions to both 3G-and-beyond inter/intra core network and the mobile user. Public key security mechanisms to protect operator’s core networks seem to gain ground and protocols like IPsec and SSL, seconded by PKI, can support the continuous growth of diverse technologies and solve inter-operator many-to-many modeled trust relationships. From the user’s side we present solutions, which far enhance authentication procedures and end-to-end communication model trust. We argue that PKI can become a promising candidate, which offers the competitive framework to overcome symmetric key based security inefficiencies and provide powerful solutions to protect both network core signalling and user’s data from potential intruders. |