The project focused on one of the most prominent FI technologies, namely Information-Centric Networking (ICN) and investigated its application in hybrid satellite and terrestrial network configuration scenarios. ICN constitutes an alternative communication paradigm to the conventional, IP-based internetworking, which is based on accessing named-content in the network, instead of host-to-host communication as in today's Internet.
φSAT proposed a novel reference architecture, which integrates the ICN architectural components into the satellite network (see Figure 1), supporting a wide variety of use cases. Considerable benefits are derived from the integration of the wide-area coverage and native broadcast/multicast capabilities provided by satellite networks, together with the FI architecture that supports content- and information-centric data exchange.
Figure 1: Satellite-assisted Information-Centric Networking (ICN) Architecture
click for larger image
φSAT has selected the Publish-Subscribe paradigm, as one of the most popular flavours of ICN. PS involves three major entities: the publishers, the subscribers and a name resolution (RendezVous) service.
Publishers hold the role of information providers, advertising the availability of information items by issuing publication advertisements.
Subscribers are information consumers, who express their interest for specific information items by issuing subscription requests.
The RendezVous service maps information item names or identifiers to the actual items, locating the publishers who can provide the information items that satisfy the consumers' subscriptions. Following name resolution, a forwarding path from the information providers towards the information consumers is created.
The publication and subscription operations described above do not have to be in sync. Moreover, publishers and subscribers - the principal actors of the architecture - do not have to be fully aware of each other: they only need to be aware of the information that they want to exchange. The above properties allow efficient support for multicast, mobility and multihoming.
The aforementioned ICN functions (publication, subscription, rendezvous service, forwarding) need to be integrated in the hybrid satellite/terrestrial network. Depending on the scenario, these functions can be implemented either in the satellite gateway, in the satellite terminals or even onboard the satellite.
Furthermore, a survey on security solutions designed for ICN architectures is performed. Among the surveyed technologies, four ICN-compatible security mechanisms, enabling access control, content authentication, subscriber privacy and forwarding plane availability respectively, are selected for φSAT, adapted accordingly and integrated into the reference architecture.
For proof-of-concept validation and assessment purposes, a lab-based emulated testbed was developed, based on the OpenSAND satellite emulator and the Blackadder publish-subscribe ICN platform. The use cases tested (video multicast, cache-assisted file transfer, Voice-over-ICN, multipath delivery, scalable video transmission, ICN-assisted mobility, access control, content authentication, subscriber privacy, forwarding plane availability) illustrate the added-value introduced via the satcom/FI synergy.