• Underwater Acoustic Sensor Networks
• Temporal Graphs
• Argo Project
• Delay Tolerant Networks

Underwater Acoustic Sensor Networks (UASN) represent a novel technology for monitoring the underwater environment. However, underwater communications through acoustic modems rise several networking challenges for UASN.
In our work, we study the possibility to use Opportunistic Routing to overcome the limitations posed by the acoustic communication channel in UASN.
For our study, we used a real-world mobility dataset obtained from the Argo project. In particular, we used data produced by the 51 free-drifting floats deployed on the Mediterranean Sea for approximately one year to build a fictitious network called the Argo Underwater Sensor Network. Then we analyse some important properties of the underwater network we built. Specifically, we analyse the network degree, density, properties of the connected components, properties of contact and inter-contact time while varying the connectivity degree of the whole network.
We then consider four known opportunistic routing algorithms, namely Epidemic, PROPHET, SprayAndWait and Direct Delivery, with the goal of measuring their performance in real conditions for UASN. We finally discuss the opportunities arising from the adoption of opportunistic routing in UASN showing that, even in a very sparse and strongly disconnected network, it is still possible to build a limited but working networking framework.