If you are planning to kick off YouTube TV in SFO, how much bandwidth would be required?
Google- Ana Rodriguez
First, I’d like to make sure we’re aligned on the exercise. A few questions:
- I’m not super familiar with Youtube TV. If I remember correctly it allows you to stream TV channels into your devices by paying a monthly fee. Is that correct?
- Ok, so by having “youtube tv” in SFO do you mean streaming tv channels at the airport’s TVs? Or allowing users to connect to the airport wifi to stream any channel on their personal devices? Both.
- Are we trying to calculate streaming between Youtube’s servers and the SFO tech hub? Or between the SFO tech hub and passengers’ personal devices? Both.
- Is there a streaming solution implemented to have one stream of each channel from Youtube to SFO and then broadcast x times to each personal device? Or there is one stream from each personal device directly to Youtube’s servers? Let’s assume there is one stream per channel from youtube to SFO, that gets broadcasted x times from there to users devices. Ok, then I’ll ignore the stream from SFO to youtube given it’s insignificant compared with the broadcast bandwidth within the airport to each passenger.
- What video quality level should we assume? 4K.
Ok, so here’s what I’d like to know:
- How many passengers we have at the SFO airport on a given year.
- What % of those would connect to the wifi.
- What % of those would connect to the wifi and stream tv.
- For how long on average they stream tv.
- Average bandwidth required per second for 4k streaming. I believe it’a around 25Mbps = ~3 MBs per second
| How many passengers we have at the SFO airport on a given year. | What % of those would connect to the wifi. | What % of those would connect to the wifi and stream tv. | For how long on average they stream tv. | Total |
| Nr of gates * hours open in a day / nr of average hours per plane at gate * utilization of gates * utilization of planes * average plane capacity * 30 days / month * 12 months per year * 2 (arriving passengers + departing passengers on each airplane) * passengers per flight
Nr of gates = ~30 per terminal * 4 terminals = 120 120 * 20 / 2 *.9 * .8 * 30 * 12 * 2 * 250 = ~150M passengers per year |
Arriving passengers = 10%
Departing passengers = 20% |
Arriving passengers = 20%
Departing passengers = 40% |
Arriving passengers = 10 mins = 600 secs
Departing passengers = 30 mins = 1800 secs |
75M*.1*.2*600 + 75M*.2*.4*1800 = ~12.5 T secs per year |
Total bandwidth = ~12.5T secs per year * 3MB per second = ~37.5 Trillion MB per year = 37.5 PB per year
For a more precise calculation I would use 1,024 conversion rate for MB to GB to TB to PB.