The quality of Internet access for mobile users may suffer from highly variable communication characteristics (packet loss, delay, throughput) and from temporary disconnections. The former occur as a result of changing radio properties, handovers, or variable system load, the latter whenever wireless coverage is insufficient. While quite some research has tackled improving radio coverage to keep users always best connected and numerous approaches pursue improving wireless performance and robustness, these often assume a greenfield deployment or a tight integration with operators. We present the mobility support system architecture developed in the CHIANTI project. While building on related work in various technical respects, the CHIANTI architecture is specifically designed to be instantly and incrementally deployable in today’s Internet landscape, considering real-world legal and deployment constraints, and supports roles of different (independent) players. We also report on our...