I see a lot of viewers are having queries Where & How to Watch Rio Olympics on top streaming channels such as CBC, NBC etc. While there are so many free streaming sites which are illegal everywhere on internet, but be wary those might be filled with annoying ads and spam. So it’s better to opt for official channels in different language depending on your preference.
You can watch Rio Olympics games online on NBC channel. They have dedicated channel for Summer Olympics coverage. But it is only available in USA. Likewise there are other channels which are broadcasting Olympic Games online in particular countries.

Country - Channel
Brazil - Rede Globo, ESPN, Fox Sports
Canada - CBC (FREE)
China - CCTV (FREE)
France - Canal+
Germany - ARD, ZDF (FREE)
Russia - C1R, VGTRK, NTV Plus
UK - BBC (FREE)
USA - NBC
Austria - ORF (FREE)
Ireland - RTE (FREE)
Spain - RTVE (FREE)
Czech Republic - CT (FREE)

How can I watch Rio Olympics online?
In order to get complete access to free channels regardless of any geographical barrier, you have to be connected with respective country. An easy way is to connect via VPN and change your IP address/location. For example you can Watch Rio Olympics online on NBC Free by connecting to US IP address and enjoy streaming even if you are residing in any part of the world. You can find the complete streaming guide on USA VPN http://www.usavpn.com/how-to-watch-olympics-online/