  This paper discusses the design, implementation and field trials of WiMesh -
a resilient Wireless Mesh Network (WMN) based disaster communication system
purpose-built for underdeveloped and rural parts of the world. Mesh networking
is a mature area, and the focus of this paper is not on proposing novel models,
protocols or other mesh solutions. Instead, the paper focuses on the
identification of important design considerations and justifications for
several design trade offs in the context of mesh networking for disaster
communication in developing countries with very limited resources. These
trade-offs are discussed in the context of key desirable traits including
security, low cost, low power, size, availability, customization, portability,
ease of installation and deployment, and coverage area among others. We discuss
at length the design, implementation, and field trial results of the WiMesh
system which enables users spread over large geographical regions, to
communicate with each other despite the lack of cellular coverage, power, and
other communication infrastructure by leveraging multi-hop mesh networking and
Wi-Fi equipped handheld devices. Lessons learned along with real-world results
are shared for WiMesh deployment in a remote rural mountainous village of
Pakistan, and the source code is shared with the research community.
