We will learn about the lowest level of communication protocols in IoT - the MAC layer. This is the layer that deals with all the unpleasant and challenging situations that come about through the use of RF in challenging environments. We will learn about mechanisms to efficiently send and receive data, with low power, discover and pair with other nodes, deal with transmission collisions, and so on.

We will talk about mesh networking, a set of techniques that allow wireless devices to work together to discover and maintain working paths to destinations. These techniques enable communication across multiple hops, by having nodes help each other out, routing through multiple layers of intermediate proxies to construct paths to any destination that needs to be reached. The techniques we talk about in this lecture form the foundation for many operations needed to be conducted in IoT, such as dissemination, replication, multicast, service discovery, and so on.

We will study the next layer up of distributed algorithms that are used in IoT networks. We will continue our exploration of mesh routing, and describe how such techniques can be used to place data at geographic locations, forward in "intermittently-connected" setting, perform multicast, and more.