  Mobile Edge Computing (MEC) has been gaining significant interest from first
responders and tactical teams, primarily because they can employ handheld
mobile devices to form a computing cluster (for computing tasks like face/scene
recognition, virtual assistance) when connectivity to the cloud is not present
or it is limited. High user mobility in first responder or tactical
environments makes MEC challenging, as wireless links observe substantial
fluctuations. Typical cloud-based coordination (e.g., ZooKeeper-based service
discovery and coordination, device naming, security) needed by edge computing
tasks cannot work in these environments. Driven by the need for a resilient and
lightweight coordination service, in this paper, we design and implement \ek to
provide cloud-like coordination for MEC systems. It provides naming, network
management, application coordination, and security to distributed edge
computing applications. It maintains an edge cluster among devices and
intelligently stores its data on a group of replicas to guard against node
failure and disconnections. We provide a full-system implementation of
EdgeKeeper for Android and Linux platforms. We have integrated EdgeKeeper with
existing MEC applications and performed real-world performance evaluations in a
wide-area search and rescue operation conducted by first responders, which
proves it to be lightweight and suitable for mobile devices.
