A4-Mesh is a SWITCH/AAA joint project among the University of Bern, the University of Neuchâtel and SWITCH. It develops a completely functional wireless mesh infrastructure, which enables broadband network access for researchers in remote locations. The A4-Mesh wireless mesh network provides authentication, authorization, accounting, and auditing. The A4-Mesh authentication and authorization are fully compatible with the existing SWITCHaai. They protect a network against illegitimate stations by granting access to the authorized machines and users. In addition, the A4-Mesh project offers detailed accounting to enable infrastructure and cost-sharing among different organizations.

A4-Mesh offers a cost-efficient and robust way to interconnect remote sites to a network backbone.
In the course of this project, we have set up a wireless mesh network in the area of Crans-Montana and Emmental for connecting hydrological measurement stations to the fiber network backbone and to provide network access for environmental researchers in the field. Using this experience, we show how wireless mesh technology can be used to provide communication facilities for environmental research in the field or to easily extend coverage of campus networks.