Current communication approaches assume network associations as a prerequisite to both content discovery and access. This network-centric paradigm incurs substantial communication and time overhead, as devices build knowledge of content availability only after blindly associating to a network. In pervasive mobile networking, this prerequisite and associated overhead prevents devices to efficiently identify desired communication partners, i.e., devices running an application or providing content of interest, within the broad mass of devices in communication range as found in everyday scenarios. SO-Fi, instead, realizes content-centric wireless networking by enabling pervasive content discovery before establishing a network infrastructure. SO-Fi builds on the IEEE 802.11 wireless broadcast medium to instantly achieve a discovery scope covering all devices in communication range. Realizing content discovery outside of secure network associations, SO-Fi supports use-case-specific communication security, i.e., confidentiality, WPA2 network security, DoS robustness, and user authentication. We show SO-Fi's feasibility and performance through real-world experimentation. Indeed, SO-Fi makes instant, content-centric wireless networking readily accessible to application designers.

Typical scenarios in the city or on campus, show a high proliferation of wireless communication devices such as smartphones, laptops or netbooks. Wireless 802.11 networks between these devices allow for a spontaneous exchange of content or provision of services without the need for infrastructure-based services. However, the above mentioned proliferation of devices and therefore large number of networks hinders users in identifying and selecting the network that serves a specific request. We propose an approach to client-driven content-centric wireless networking in which the user specifically signals his request for a user, content item or service via 802.11 management frames. Upon reception of these frames, wireless devices that serve this request establish a dedicated wireless network on-demand. Our approach seamlessly integrates into the 802.11 association process and therefore provides support for unmodified wireless devices. Furthermore, by leveraging the wireless broadcast medium, we achieve pervasive service and peer discovery without the overhead of iterating through existing networks or running a traditional service discovery protocol.

Rapidly changing link conditions make it difficult to accurately estimate the quality of wireless links and predict the fate of future transmissions. In particular bursty links pose a major challenge to online link estimation due to strong fluctuations in their transmission success rates at short time scales. Therefore, the prevalent approach in routing algorithms is to employ a long term link estimator that selects only consistently stable links - PRR >; 90% - for packet transmissions. The use of bursty links is thus disregarded although these links provide considerable additional resources for the routing process. Based on significant empirical evidence of over 100,000 transmissions over each link in widely used 802.15.4 and 802.11 testbeds, we propose two metrics, Expected Future Transmissions (EFT) and MAC3, for runtime estimation of bursty wireless links. We introduce the Bursty Link Estimator (BLE) that, based on these two metrics, accurately estimates bursty links in the network rendering them available for packet transmissions.