Big UK ISPs Clarify the Confusion over Network Level Internet Filters - ISPreview UK: "In essence what Claire Perry has proposed and what ISPs are adopting appears to be Active Choice Plus but the devil is in the detail and it’s important to understand the subtleties involved before drawing any conclusions.
Firstly we already know (since May 2013) that all of the major ISPs either have or will soon launch network level filtering by the end of 2013 (here). A “network level” solution means that the ISP controls the filtering at its end of the service and this allows the restrictions to be imposed across all your connected devices.
But will it be enabled by default? Well not quite. According to the ISPs, all customers (both new and existing) will at some point be presented with an OPTION to enable or disable the related Parental Controls" 'via Blog this'