The following is a quick hack together page to test the bandwidth used by streaming TV. It was inspired after numerous posts on forums where users experience breakup and poor buffering on lower speed broadband connections. In particular a thread about YouView IPTV prompted me to perform some tests of my own.
It is intended to be a guide of real time bandwidth used whilst viewing IPTV content and makes no claim to be accurate.
Monitoring bandwidth in use from streaming TV can be difficult as most devices used for streaming TV don't have any form of bandwidth monitoring. The way streaming content is delivered (buffered) to a PC also makes it hard to see what bandwidth is used in real time.
To check our baseline speed we downloaded and observed the speed of a 1GB test file from thinkbroadband. The result was a fairly level average of 16Mbps.
The idea behind the following tests are to stream content to various devices whilst simultaneously downloading the 1GB file. If we subtract the average download speed during the tests from the available bandwidth then we should have a rough idea of how much bandwidth is being used by the streaming media content.
Test 1 - iPlayer content to i-pad
Streaming BBC 4 -Natures Microworlds to iPad (wi-fi).
The above images show evidence of the buffering speed of the stream. Highs were around 16 Mbps, lows were just shy of 13Mbps, giving a spread of 3Mbps. DU Meter showed a mean average of around 14.5 Mbps, meaning as expected an average speed of 1500 kbps for an SD stream.
Spread = 3 Mbps
Average = 1500 kbps
Test 2 - iplayer content to TV via Apple TV
Streaming BBC 4 Natures Microworlds to TV via Apple TV over AirPlay.
The above test showed slightly more variance during the stream.
At the very beginning of viewing the TV screen displayed evidence of Adaptive Bitrate technology and switched to a better quality stream (800 -> 1500 stream).
Although the stream file was the same as the first test, for some reason there seemed to be slightly less available bandwidth on average for the 1GB file. Spread was larger and at times down to 11 Mbps or below. Average was nearer 14 Mbps meaning more like 2Mbps used for the stream.
Spread = up to 5Mbps
Average = 2 Mbps
Test 3 - HDTV
Streaming BBC1 Dr Who HD quality stream to Smart TV via Toshiba Places (LAN).
Eventually settled to a consistant buffered stream. Lows were generally around 10Mbps, although patches of 8Mbps were seen, meaning a variance of up to 8Mbps, but common average on DUMeter of around 12.5 Mbps. Resulting in an average of 3.5Mbps for a HD stream.
Spread = Up to 8 Mbps.
Average = 3.5 Mbps
Test 4 - Streaming to PC
Streaming BBC 4 -Natures Microworlds to PC (LAN)
Unable to conclude any useful data due to large spread and variance of the buffered stream.
Test 5 - Check bandwidth
Streaming tests completed but recheck base download speed is still a fairly static 16Mbps throughput.