to assemble the pages displayed by web browsers. Mobile services, and the mobile devices consuming them, have made this trend even more evident, and virtually all content mobile users see is the result of multiple steps of real-time, on-the-fly processing. Prominent examples include videos, that are transcoded to match the screen size and resolution of the device playing them, and social networks, which decide what to show to their users based on their identity and location.

[*Where*]{} such processing ought to be performed is a fundamental question. The traditional approach was to use ad hoc servers placed within each content provider’s network; cloud computing, with shared virtual servers placed in the Internet, provides a more efficient but substantially equivalent alternative [@5gcloud]. The recent multi-access edge computing (MEC) paradigm takes a different approach: it envisions moving services, i.e., the servers providing them, as close to mobile users as possible. Servers will not be localized in remote datacenters, but at different entities within the mobile core network itself, from core switches to base stations [@noi-pof; @noi-workshop]. Similarly to cloud scenarios, there is a measure of cooperation between content providers and network operators. The servers deployed by the network operators will run services 