The 100 Gbit/s problem in your network

Tue Feb 12 15:32:11 UTC 2013

On 12/02/13 14:14, fredrik danerklint wrote:
> Just to clarify, Patrick is right here.
>
>
> Assumptions:
>
> All the movies is 120 minuters long. Each movie has an average bitrate 
> of 50 Mbit/s.
>
> (50 Mbit/s / 8 (bits) * 7 200 (2 hours) / 1000 (MB) = 45 GB).
>
>
> That means that the storage capacity for the movies is going to be:
>
> 10 000 000 * 45 (GB) / 1000 (TB) / 1000 (PB) = 450 PB of storage.
>
>
> Some of you might want to raise your hand to say that this quality of
> the movie is to good. Ok, so we make it 10 times smaller to 5 Mbit/s
> in average:
>
> 450 PB / 10 = 45 PB or 45 000 TB.
>
>
> If we are using 800 GB SSD drives:
>
> 45 000 TB / 0,8 TB = 56 250 SSD drives!
>
> (And we don't have any kind of backup of the content here. That need
> more SSD drives as well. And don't forget the power consumption).
>
>
> So over to the streaming part.
>
> 10 000 000 Customers watching, each with a bandwidth of 5 Mbit/s =
> 50 000 000 Mbit/s / 1000 (Gbit/s) = 50 000 Gbit/s.
>
>
> We only need 500 * 100 Gbit/s connections to solve this kind of
> demand. For each ISP around the world with 10 000 000 Millions
> of customers.
>
>
> Will TLMC be able to solve the 100k users watching 10 different
> movies? Yes.
>
> Will TLMC be able to solve the other 10 Million watching 10 Million
> movies. No, since your network can not handle this kind of load in
> the first place.
>
>

Fortunately, we have some fascinating recent research on exactly this:

http://www.land.ufrj.br/~classes/coppe-redes-2012/trabalho/youtube_imc07.pdf

-- N.