Data Inter-Working Aspect of Network Cooperation in 4G: The Case of Registry Composition in Ambient Networks

Fourth generation networks are foreseen as coexisting and cooperating legacy (e.g. 3G networks) and new networks (e.g. mobile ad-hoc networks). Network cooperation is no novelty - roaming between 2G/3G cellular networks is just one example. However, network cooperation as envisioned for 4G goes beyond the static cooperation of today. Ambient networks are a new architectural concept for 4G networks. Network composition is a concept of ambient networks which will allow scalable and automatic cooperation between heterogeneous networks. Ambient networks can host various registries (e.g. relational databases, UDDI). When ambient networks compose, the hosted registries have to follow suit and compose. Two problems are related to registry composition: interface (i.e. protocol and APIs) inter-working and data inter-working. Data inter-working requires overcoming content heterogeneity (e.g. type, format and granularity) for giving clients a uniform access to heterogeneous data sources. This paper deals with the data inter-working aspects of network cooperation in 4G and focuses on the specific case of registry composition in ambient networks. A novel architecture is proposed, along with its architectural components and the inter-working related procedures. A proof-of-concept prototype is also described.