I'm not sure if I met prisoners during the years, but I already came in contact with some younger people who were "stumbling" over common values like going to school, not stealing, avoiding drugs ... and these were sent to this walk instead of other kind of detention or social work. I haven't followed if it was just a experiment or is done on a regular base.
And you may rethink your idea of prisoners. Being in prison does not always mean, staying for months/years behind walls. Some prisoners do their daily work ouside in normal offices or factories and only come back to stay in prison at night.
Do you know?: It's an actual discussion to introduce free wifi/internet in prisons in Berlin (the discussion is mainly about costs and jealousy, because still not every citizen outside will be able to get it). The newly built detention centers already have it.