End-to-End TCP for Sensor Networks

Wireless sensor networks (WSN) enable the efficient collection of sensor data. They are, however, not useful when operated in isolation. To fulfill the vision of the Internet of Things, WSNs must be connected to an external network through which monitoring and controlling entities can reach the sensors. Since sensor nodes are usually battery-driven they cannot have their radios turned on continuously since the radio is the main energy consumer even when only in idle listening and neither transmitting nor receiving. Therefore, sensor nodes are duty-cycled, i.e., they turn off their radio most of the time. Neverthless, there exists data collection protocols, e.g. CTP [1], that achieve a long life-time. Nevertheless, duty-cycling makes TCP operation in sensor networks inefficient even though there are some optimizations that we have devised ([2] ,[3]).
Recently, Ferrari et al. have presented a new networking paradigm, the "wireless bus", that turns a multi-hop sensor networks into an infrastructure similar to a shared bus, where all nodes are potential receivers of all data [4]. In this project, we will make the wireless bus TCP-ready and study the end-to-end TCP performance from external Internet hosts to sensor nodes within a sensor network that is based on the wireless bus.

[1] O. Gnawali et al., "Collection tree protocol", ACM SenSys 2009
[2] A. Dunkels, J. Alonso, T.Voigt, H. Ritter, "Distributed TCP Caching for Wireless Sensor Networks", MedHocNet 2004
[3] T. Braun, T. Voigt and A. Dunkels, "TCP support for sensor networks", WONS 2007
[4] F. Ferrari, M. Zimmerling, L. Mottola and L. Thiele, "Low-Power Wireless Bus", ACM SenSys 2012

• Thiemo Voigt
• Kasun Hewage
• Venkatraman Iyer

You can find the source code at
https://github.com/kasunch/lwb

This project is funded by .SE, the Internet Infrastructure Foundation.