02488nas a2200313   4500000000100000008004100001653003100042653002800073653002300101653001400124653002600138653001300164653001900177653002800196653002300224653002700247100001600274700002100290700002000311700002000331700001500351700001400366700001600380700001800396245010200414856005900516300000800575520159100583       2018                            d10aBiological system modeling10aBroadband communication10acommunity networks10aEconomics10aincentive mechanisms.10aInternet10asustainability10aSustainable development10aTelecommunications10aWireless communication1 aP. Micholia1 aM. Karaliopoulos1 aI. Koutsopoulos1 aLeandro Navarro1 aRoger Baig1 aD. Boucas1 aM. Michalis1 aP. Antoniadis00aCommunity Networks and Sustainability: a Survey of Perceptions, Practices, and Proposed Solutions  uhttp://people.ac.upc.edu/leandro/pubs/cn-sust-ieee.pdf  a1-13 aCommunity network (CN) initiatives have been around for roughly two decades, evangelizing a distinctly different paradigm for building, maintaining, and sharing network infrastructure but also defending the basic human right to Internet access. Over this time they have evolved into a mosaic of systems that vary widely with respect to their network technologies, their offered services, their organizational structure, and the way they position themselves in the overall telecommunications’ ecosystem. Common to all these highly differentiated initiatives is the sustainability challenge. We approach sustainability as a broad term with an economical, political, and cultural context. We first review the different perceptions of the term. These vary both across and within the different types of stakeholders involved in CNs and are reflected in their motivation to join such initiatives. Then, we study the diverse approaches of CN operators towards the sustainability goal. Given the rich context of the term, these range all the way from mechanisms to fund their activities, to organizational structures and social activities serving as incentives for the engagement of their members. We iterate on incentive mechanisms that have been proposed and theoretically analyzed in the literature for CNs as well as tools and processes that have been actually implemented in them. Finally, we enumerate lessons that have been learned out of these two decades of CNs’ operation and discuss additional technological and regulatory issues that are key to their longer-term sustainability.