The public Git repositories are currently due to a denial of service attack intentionally not available. You can access git.iws.uni-stuttgart.de with your University account and a VPN. We are working on that for some public accesss especially for referrences in papers. If you are an active external developer working on code or a paper or some other repostitory please send me an email. Also if you need some code of a repo. The address is git-requests [-at-] iws.uni-stuttgart.de.
Your administrator
David Werner.