-# official debian DE repository:
-# deb http://ftp.de.debian.org/debian/ testing main contrib non-free
-# deb-src http://ftp.de.debian.org/debian/ testing main contrib non-free
-
-# official debian AT repository:
-# deb http://ftp.at.debian.org/debian/ testing main contrib non-free
-# deb-src http://ftp.at.debian.org/debian/ testing main contrib non-free
+# security updates:
+ deb http://security.debian.org/ testing-security main contrib non-free-firmware non-free
+ deb-src http://security.debian.org/ testing-security main contrib non-free-firmware non-free