this book constitutes the thoroughly refereed post-conference proceedings of the ifip-tc6 7th annual international working conference on active networks, iwan 2005, held in sophia antipolis, france, in november 2005. the 13 revised full papers and 13 revised short papers presented were carefully reviewed and selected from 72 submissions. the papers are organized in topical sections on programmable networks and heterogeneity, architectural frameworks, node architectures, and services.