The BBC iPlayer diagnostics page has a speed testing service which shows whether your current broadband speed is adequate for various BBC services, radio, TV, HD-TV etc.
Here's what a typical results page looks like:
What are the three TV categories 1500, 800 & 500?
There's nothing on the page and no mouseover either.
BTW this screenshot done at work where the connection is great, reason for asking is home speed is so much worse and there I won't get those green ticks for the more demanding services.
Best Answer
The three TV categories 1500, 800 and 500 (kbps) would seem to relate to the different resolutions you can view SD content.
1500 kbps is the required bitrate for fullsize SD (832 x 468) (just shorter than the width of the website) - this is the default size when you navigate to the TV show (assuming your connection can cope). This is also considered "Normal Bandwidth" (option at bottom of screen.)
500 kbps (or rather 480 kbps) is the required bitrate for the smaller (640 x 360) "popout" player. This is also the "Lower Bandwidth" option - selected at the bottom of the screen (which changes what you see in the main player).
I can't currently see where 800 kbps is used. However, I suspect this might be the default if your connection can't cope with the full width 1500 kbps version. I thought iPlayer used to open at a smaller size by default and there was an option to display full width (like there is with YouTube). The 800 might relate to this smaller size. However, for me it opens full width and there is no option to make it smaller (unless I open it in the "popout" player).
You can right-mouse (context menu) on the streaming video to see what "version" you are viewing. From the popup menu you can also "Toggle info console" that shows you more information. eg. "Current Stream Bitrate: 1500 kbps" / "Avg Streaming Bandwidth: 9828 kbps" / "Stream Buffer Length: 75 seconds".