ARD will together with ZDF in Germany broadcast from the Winter Olympics in Sochi. Both channels have great live streams available online, meaning that you can watch all of your favorite events online on both ARD and ZDF.
It is one month left today before the Winter Olympics in Sochi will be started, and so far I do not have any concrete information concerning what channel will broadcast what from the olympics, and also what kind of content will be available online, but considering the fact that both channels have great live streams, I believe that everything from the Olympics will be available on either the ARD or at the ZDF website, meaning that those who want to watch from the Olympics with Germany commentaries will have a very easy and joyful experience as they watch either ARD or ZDF online, from wherever they are in the world.
Do not forget though, that the live streams are only available for those surfing the Internet with a German IP address, meaning that you will need one of those to be able to watch. I have written more about how to get a German IP address in this article, and if you want more information on how to watch ARD from abroad, read this article.
If you would rather watch the Winter Olympics in English, read this article.