Next Generation Wireless Networks

As a result of the popularity of mobile devices, mobile data traffic is increasing in exponential rate. According to the Ciscos prediction this trend will continue and by end of 2018 mobile data usage will be around 16 Exabyte per month compared to the 1:5 Exabyte in 2013. To manage this enourmous mobile data traffic one single step is not adequate. We have identified three issues related to mobile data traffic management as our objective of this thesis - 1) Efficient offload using Wi-Fi Network 2) Managing Heterogeneous Traffic 3) Restricting Unauthorized Traffic.

Efficient Offload Using Wi-Fi Network / Distributed Content Storage for Just-in-Time Streaming

Uninterrupted streaming on the fly becomes an interesting issue of research in last few years. Due to low data rate, high congestion, it becomes almost impossible to deliver streaming data to users on the fly in uninterrupted fashion. Municipal WiFi networks open up a new opportunity. External memory can be easily hooked up with Access Pointi(AP) to cache popular contents, so that when request for popular contents arrives it is served locally. However, there is a limit in the amount of memory added with an AP. A single AP would not be able to cache good number of popular files. If we can find out a content distribution strategy over municipal WiFi networks where APs of WIFi networks collaboratively cache popular contents then we can serve more requests. Collaborative caching strategy should take care of uninterrupted streaming on the fly.

Managing Heterogeneous Traffic / Association control scheme for wireless mobile environment

Wireless clients associate to a specific Access Point (AP) to communicate over the Internet. Current association methods are based on maximum Received Signal Strength Index (RSSI), implying that a client associates to the AP with the strongest signal around it. The main drawback in RSSI based technology is that the global parameters are not considered during association, hence effective strategy to handle skewed geographical distribution of devices (thereby ensuring fairness) cannot be devised. However, in today's enterprise WLANs, multiple APs are getting connected to a central controller through a high speed wired backbone. As a result, modern networks are becoming semi-centralized through hybrid wired-wireless architecture that offers new opportunities to redesign protocols for future wireless. Hence, there is a need to develop smart association control schemes which will ensure higher admission along with fairness, exploiting the global view of the APs. This is particularly pronounced in light of enterprise WLANs shifting to the single wide-channel mode (proposed by Meru Networks) to reduce the problems of interference management and frequent handoff. Association control is likely to play a key role in such environments. So, the broad objectives of our research can be summarized as follows; (a) Develop an AP-guided association control strategy that exploits the global view of APs for association decision. and (b) Maximize the number of connections admitted while maintaining fairness in bandwidth allocation.

Restricting Unauthorized Traffic/ Authentication Using User's Daily Activity

There are many paid services which grant access to valuable content like movies, news, songs etc. People used to share their subscription credential of such services either under social pressure or to reduce per head subscription charge. As an effect this increases unauthorized traffic. To restrict sharing of credential, we propose a new dynamic authentication scheme based on user's daily activity. For evaluation purpose, we develop a system which considers browsing history, Facebook activities, and phone activities. Our system collects users' activities, select potential activities for challenge generation, get response from users and verify responses to authenticate.