text: Abstract Community networks differ from regular networks by their organic growth patterns—there is no central planning body that would decide how the network is built. Instead, the network grows in a bottom-up fashion as more people express interest in participating in the community and connect with their neighbors. People who participate in community networks are usually volunteers with limited free time. Due to these factors, making the management of community networks simpler and easier for all participants is the key component in boosting their growth. Specifics of individual networks often force communities to develop their own sets of tools and best practices which are hard to share and do not interoperate well with others. We propose a new general community network management platform nodewatcher that is built around the core principle of modularity and extensibility, making it suitable for reuse by different community networks. Devices are configured using a platform-independent configuration which nodewatcher can transform into deployable firmware images, eliminating any manual device configuration, reducing errors, and enabling participation of novice maintainers. An embedded monitoring system enables live overview and validation of the whole community network. We show how the system successfully operates in an actual community wireless network, wlan slovenija.
  @cite_35: This study experimentally compares the performance of three different multi hop ad hoc network routing protocols. Traditional routing protocols have proven inadequate in wireless ad hoc networks, motivating the need for ad hoc specific routing protocols. This study tests link state, distance vector and biologically inspired approaches to routing using OLSR, Babel and BATMAN routing protocols. The importance of OSI layers is also discussed. This study concludes that the routing protocol's overhead is the largest determinant of performance in small multi hop ad hoc networks. The results show that Babel outperforms OLSR and BATMAN routing protocols and that the OSI layer of the routing protocol has little impact on performance.
  @cite_47: Community networks are self-organized networks which exist all around the world. For a large number of users, they are the only form of communication in the community itself and with the Internet. All community networks maintain some database where all information about the nodes in the community network is stored. The database information is manually inserted in the database, which commonly leads to a mismatch between the documentation and reality. In this paper we present a dynamic community network mapper, complementary to the node database. We explain the goals of this approach, show the challenges and steps we took to realize such a mapper, and give initial results.
  @cite_10: Nowadays there are inexpensive WiFi devices that have fostered the deployment of wireless communities. Well known routing protocols used in the Internet do not fit well to time varying characteristic of wireless networks. This has motivated an intensive research on routing protocols for wireless mesh networks. At this time there are a number of mature and stable implementations that are being deployed in production networks. In this paper we focus on the experimental evaluation of a production Wireless Mesh network being deployed in a testbed at Universitat Politecnica de Catalunya (UPC) and a quarter of the city of Barcelona, Spain. To our best knowledge, this is the first paper where a production community wireless network using 802.11an is analyzed.
  @cite_21: This paper presents a measurement study of the topology and its effect on usage of Guifi.net, a large-scale community network. It focuses on the main issues faced by community network and lessons to consider for its future growth in order to preserve its scalability, stability and openness. The results show the network topology as an atypical high density Scale-Free network with critical points of failure and poor gateway selection or placement. In addition we have found paths with a large number of hops i.e. large diameter of the graph, and specifically long paths between leaf nodes and web proxies. The usage analysis using a widespread web proxy service confirms that these topological properties have an impact on the user experience.
  @cite_39: Nowadays, a growing number of communities of citizens build, operate and own open IP-based community wireless networks with thousands of low capacity nodes actively participating in routing the data traffic. This article focuses on one of their concerns, routing and its scalability, by presenting BatMan-eXperimental Version 6 (BMX6) and evaluating its performance. BMX6 is a low overhead and scalable mesh network routing protocol inspired by human networks. Its performance is evaluated in comparison with OLSR in terms of overhead and convergence time as networks grow in number of nodes and diameter. The results show that the convergence time and protocol overhead per node in BMX6 is not significantly affected by the addition of new nodes in contrast with OLSR, where both parameters can grow super-linearly. This confirms the excellent scalability of BMX6.
  @cite_5: Wireless Community Networks (WCNs) are created and managed by a local community with the goal of sharing Internet connection and offering local services. This paper analyses the data collected on three large WCNs, ranging from 131 to 226 nodes, and used daily by thousands of people. We first analyse the topologies to get insights in the fundamental properties, next we concentrate on two crucial aspects: (i) the routing layer and (ii) metrics on the centrality of nodes and the network robustness. All the networks use the Optimized Link State Routing (OLSR) protocol extended with the Expected Transmission Count (ETX) metric. We analyse the quality of the routes and two different techniques to select the Multi-Point Relay (MPR) nodes. The centrality and robustness analysis shows that, in spite of being fully decentralized networks, an adversary that can control a small fraction of carefully chosen nodes can intercept up to 90 of the traffic. The collected data-sets are available as Open Data, so that they can be easily accessed by any interested researcher, and new studies on different topics can be performed. In fact, WCN are just an example of large wireless mesh networks, so our methodology can be applied to any other large mesh network, including commercial ISP networks.
  @cite_31: Wireless mesh network (WMN) is a new wireless networking paradigm. Unlike traditional wireless networks, WMNs do not rely on any fixed infrastructure. Instead, hosts rely on each other to keep the network connected. Wireless Internet service providers are choosing WMNs to offer Internet connectivity, as it allows a fast, easy and inexpensive network deployment. One main challenge in design of these networks is their vulnerability to security attacks. In this paper, we investigate the principal security issues for WMNs. We study the threats a WMN faces and the security goals to be achieved. We identify the new challenges and opportunities posed by this new networking environment and explore approaches to secure its communication.
  @cite_51: Community wireless mesh networks are decentralized and cooperative structures with participation rules that define their freedom, openness and neutrality. The operation of these networks require routing algorithms that may impose additional unnecessary technical restrictions in the determination of routes that can restrict the freedom of community users. We propose a receiver-driven discretionary routing mechanism where each receiver (the intended destination of the packet) can freely specify delivery objectives and remain compatible with the collaborative approach of community networks. Each node has a unique identifier and can announce the description of its offer and also the description of its routing policy with preferences to deliver traffic to it. BMX6 provides a “hash-based profile propagation mechanism” to disseminate descriptions. This receiver-driven routing can be applied to express preferences for desirable nodes and paths, or to restrict traffic to trusted nodes enabling trust and security aware routing. We validate our contributions with a proof of concept implementation of key concepts, as an extension of the BMX6 routing protocol, that confirms its feasibility and scalability.
  @cite_25: This paper proposes the performance evaluation and comparison of the main topology-based routing protocols commonly used in wireless ad hoc networks: DSDV, OLSR, AODV and DSR in a different environment such as wireless mesh network. It provides an overview of available solutions based on detailed simulation study. The performance comparison is done with regard to the network size, network load and the mobility of nodes. Based on the experimental results, we recommend using particular protocols in certain conditions.
summary: A lot of research has been done into individual wireless mesh network building blocks. Among them are routing @cite_35 @cite_39 @cite_51 , security @cite_31 , and analyses of topologies, performance, mobility @cite_21 @cite_25 @cite_47 @cite_10 @cite_5 . But research into community network management solutions and best practices still remains scarce. This is why most of the related work in this area comes from the individual community networks which have each developed its own solutions, practices and philosophy.