This series of articles was also posted on 10GbE.net.
At CES this week Netflix, announced streaming support for SuperHD and 3D. For a select few in the back of their booth, they also showed off UltraHD (4K) streaming. Some of you may know that Hulu Plus already supports HD streaming, but NetFlix is the 800Lbs gorilla, and when he moves people pay attention. Also this month we learned that Redbox has partnered up with Verizon to deliver their new Redbox Instant streaming service for the same $8/month that NetFlix charges. Let us not forget that Amazon Prime also offers HD streaming, so there are plenty of choices now for streaming quality commercial content.
Now, to be honest, most of my NetFlix streaming is still on my iPad, and the content is older TV shows that are likely only stored in Standard Definition (SD) format in the “cloud”. Also like most folks these days my primary TV is one of those jumbo sets, but unlike my college sophomore daughter who exclusively uses a Roku box, ours is still connected to a digital Time Warner set top box. So what does all this have to do with 10Gb Ethernet?
Streaming content comes from service providers and content delivery networks that make up the “cloud”. As we move from SD to HD formats like SuperHD, 3D, and soon UltraHD their servers and networks will be bursting with the new demand for bandwidth. What is the actual impact of moving to these high-resolution options?
Here are some rough numbers that I’ve pulled from Wikipedia’s page on H264 stream encoding:
Format Bandwidth SD Equivalent H264 Level
SD (480i) 5Mbps 1X 2.1
SuperHD (1080p) 25Mbps 5X 4
UltraHD (3840p) 300Mbps 60X 5.1
How does this impact the video servers on the other side of the network providing your content? Well if they’re still using Gigabit (GbE) links, and only serving up SD streams they can support about 150 customers per network port. When they move to 10GbE that jumps up to 1960 streams (10GbE links are a bit more efficient) per port. Most of the Content Delivery Networks (CDNs) have already moved to 10GbE for this initial boost. It becomes even more affordable when they utilize dual port cards so they can provide nearly 4,000 customers service from a single server.
Now along comes HD, and these servers with dual 10GbE ports can only handle about 800 customers. Once those customers upgrade to UltraHD that number drops to 65 customers/server. Wow from 4,000 to 65, and those 65 are consuming the same number of bits/sec so the backend storage demand remains constant. Server managers have to balance demand, people wanting to watch videos, with the hardware capability of both their storage & network infrastructure. As we saw on Christmas morning when NetFlix’s streaming service crashed for 24 hours, it’s not hard to miscalculate maintaining this balance.
Stay tuned, and next week I’ll share what technology is available to ease the burden on these video server vendors and server managers.