Jkaptive is a simple captive portal without RADIUS and thus, without total security, but at the same time. without too much hassle. The reason behind this is because a lot of site administrators don't need tight security - their site is just a café which offers free internet access on an unsecured WLAN access point connected to the internet and they need a ticketing system to make it cumbersome for average people to use this offering without actually buying a single coffee.
Jkaptive itself just presents the login page,checks the token and places netfilter rules. Telling apart ticketed from unticketed traffic is done through Linux' netfilter.
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