Starting at midnight GMT, many sites started showing their IPv6 servers as being available. Here, pale yellow-green means the site will tell a visitor that an IPv6 server is available for visitors from all the points on the Internet from which the RIPE Internet registry is measuring. Darker colors show lower levels. Many sites already advertised their IPv6 servers, and some still don't, but a few toward the top, including Yahoo, Google, Bing, Facebook, YouTube, and Cisco, show a transition to IPv6 availability.