Whether you are new to the field of Fixed Broadband Wireless Access Network (FBWA) or a salty old sea dog in my opinion the white paper “How to Build and Manage a Successful FBWA Business” [edit 16/06/2011 regretfully this article is no longer available online, sorry] is an excellent read. WISPs and WiFi hotspot network operators fall within the FBWA category, and even if you plan to run a single commercial WiFi hotspot, with one access point, I would recommend you read this article.
The article makes an important point in that providing a highly reliable service is a significantly greater challenge in the FBWA space than in the cellular mobile telephony service (CMTS) space. It does this by reminding the reader that reliability requirements in terms of backhaul links are significantly more stringent in FBWA networks than in CMTS networks, since with the former, backhual link downtime generally results on consumer downtime since one has a single point of failure, whilst in the latter, service degradation is the result, which is generally preferable to having no service at all.
In a nutshell, the article suggests, in my opinion, that you better know what you are doing if you are going to provide a high quality, highly reliable FBWA network. In my mind, if you are operating a commercial prepaid FBWA network, the demands are even greater and potentially commercial WiFi hotspot operations present the greatest challenge if you are serious about your service levels (and if you are not, thankfully in South Africa there is the Consumer Protection Act or the old fashioned way, consumers voting with their feet).