Topic 5: design of reactive, low-power MAC protocols

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Heap of batteries

(Picture from Jacques Grenier)

Although the batteries' market is going well, it is not easy to change them regularly on sensors, especially if those sensors are deployed in areas that are inhospitable or difficult to access.

The energy consumption of wireless sensors is mainly due to the radio component. Therefore, it is important to reduce its consumption by deactivating it as often as possible. This approach has the drawback of increasing the reactivity of the communication protocols, as no transfer can occur while the radio component is switched off.


The objectives of our team with respect to this topic are to study the tradeoff between reactivity and energy consumption. The protocols of interest are those able to take into account dynamic networks, where devices are mobile. In such networks, it is not possible to keep an accurate view of the topology for example.

Several approaches have already been proposed. One of them consists in identifying several types of end-devices according to their resources, and to allow them to work according to a different mode. Another approach is to combine the features of several layers of the OSI stack (for instance the MAC sublayer and the routing layer) in order to reduce the delays in forwarding the frames.

Keywords: tradeoff between reactivity and energy saving, mobility, dynamicity, IEEE 802.15.4, Zigbee.


Nassima Hadid is a PhD student, funded by a grant of the French ministery. She is studying a mechanism to communicate aside, that is, that allows devices having a lot of energy to work together while the rest of the devices sleep.

Nancy Rachkidy is a PhD student working on the cross-layering between the MAC sublayer and the routing layer. The goal of this cross-layering is to optimize the medium sharing of the MAC sublayer and to accelerate data forwarding, which has the consequence of improving the reactivity of communication protocols.


Current participants

Michel MissonFull professor

Scientific contact: Michel Misson.


AuthorsTitleConference or journalDateTopicMiscellaneous
Gérard Chalhoub, Nassima Hadid, Alexandre Guitton, Michel MissonDeference mechanisms significantly increase the MAC delay of slotted CSMA/CAICC (International Conference on Communications)June 2009T.4 and T. 5

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