Troubleshooting Assistance Services in Community Wireless Networks

We have identified new services intended for users and administrators of community wireless networks. Troubleshooting assistance services will assist the users during solution of communication problems, gathering data for expert analysis, informing the user about the state of the network (including outages), and so forth. Network administrators will be provided with a unique tool supporting the network analysis, operation, and development. We have mainly focused on the use cases and prerequirements—the problem of topology discovery. 1. Introduction Community Wireless Networks (CWNs), the phenomenon of the last decade, differ in many ways from the usual enterprise computer networks or access networks of Internet service providers (ISPs). We have to address common problems appearing in these networks with regard to their specifics. Our experiments were done in local community wireless network—http://www.hkfree.org/—operating on the territory of Hradec Kralove town and the surrounding conurbations. 2. Community Wireless Network Characteristics We deal with the specifics of CWNs networks in the Czech Republic in this paper, but many conclusions can be generalized. We will briefly discuss individual differences. History of CWNs in the Czech Republic starts in 2002 when in Prague and other places the first small neighbour networks appear. Their advantages are economies of scale, removal of margin of a commercial ISP, and also the possibility to influence the functioning of the network itself and to contribute to it (e.g., to implement own services related to the network). The development of these networks was stimulated by far too high price of fast and unlimited internet connection (broadband) and by decreasing price of electronics, especially components for building wireless radio networks (WiFi cards) [1]. Later, they evolved from unorganized neighborhood networks to large organized communities forming a civic association or other legal forms. Other terms such as Mobile Ad Hoc Network (MANET) and Wireless Mesh Network (WMN) are related to the CWNs; Mahmud et al. [2] explains these types of network in detail. CWNs, at least in the form in which they occur in the Czech Republic, do not fully comply with the definition of either MANETs or WMNs. Its technical characteristics are closer to the ISP access networks, with the different last mile and backbone technologies. For example, unlike ADSL, they use low-cost WiFi outdoor links. Spontaneous changes in topology and outages are more frequent. Worldwide CWNs are typically rather simple (often homogeneous) WMNs