Matt-J.co.uk : Ramblings

While waiting for a few things to install / copy before starting a huuge project (more laters) I thought I would take this time to have a small ramble about the new sun streaming system I was setting up last week;

It’s called the StreamStar, or the sun streaming system (depending on whether you like snazzy marketing names, or more sensible names that better describe the product you are about to buy :P) And it’s suns new solution for massively parallel simultaneous IP Video streaming.

The Jist of it is this:
“The Sun Streaming System’s revolutionary design scales up to provide personalized unicast streaming to every television set – enabling operators to offer new personalized television services faster and more economically, such as customized content per subscriber, targeted advertising, high-definition video streaming and time-shifted television and video on demand with anything, anytime, anywhere television personalized for everyone. The result – operators can increase subscriber revenue at dramatically lower technology costs” - Sun Microsystems (http://www.sun.com/servers/networking/streamingsystem/features.xml)

Roughly translated, This thing is seriously impressive;

• It has the capability to stream 160,000 2Mbit/second streams to individual users (unicast) SIMULTANEOUSLY! While providing each user the ability to stop / pause / rewind / fast forward etc.
• The smallest setup comes with 24TB of back end secondary (Hard disk) storage, Enough to store 9,400 Hours of video at 2Mbit.
• The system can scale up, allowing each component in the system to have one or more systems dedicated to each task, for more processing power if need be (and hot fail over), and allowing the connection of upto 32 x4500 (Back end storage servers) Allowing for a 768TB Content library.

The operation of the system is pretty cool too, On top, there is a web and CLI interface for the administrator to add content, provision new servers into the system etc (More regarding this side of the kit when I’ve had more of a chance to look around)

For now, I just know about the Setup.
The streaming system is made up of a number of components, the storage servers (x4500’s) which have already been discussed. Then there are a number of 1U systems (X4100’s) that manage the health of the system, as well as controlling the system and managing the establishment and control of each users video stream.(Distributed software that all loads via net boot from one of the X4100’s) Last but not least, is the Streamstar Video switch, but more on that later.

The control nodes (X4100’s as mentioned above) co-ordinate (via a seperate, private 1GB/s Switched link) each of the systems..

say a user requests a stream (Most likely through an ISP / cable providers content management system/set top box.. but anyway);
the control nodes (using open standards and protocols such as RTSCP/RTSP) will establish a session with the user, at the same time, will order the back end storage to output the requested content to the streamstar video switch (if not already cached in the switch.. More on this later), which will have been told (by the control nodes also) what to do with the stream, how to packet-ise it up into UDP packets, and the destination IP etc, and it’s doing this for up to 160,000 different streams! at the same time!
The main component that makes this possible (Apart from the impressive compute/data throughput of the other sun systems (ie the X4500)) is the streamstar switch, It is basically a large cache for media bearing UDP packets, that allows control messages from the control nodes which tell it which UDP data packets to assign which IP’s too, It will then send this data out to the operators network via one of it’s 32 (yes.. 32!) 10Gb/s XFP Fiber ports!

(the impressive thing here, is that since the actual client’s session is controlled by one or more of the x4100 control nodes, the streamstar switch only needs to fire out the relevant UDP packets (the actual video stream)..
any control packets from the client are returned to the control nodes that co-ordinate this whole process. Because of this, (apart from the 1Gb/s Copper control link) the streamstar only ever needs to receive (RX) from the x4500 storage array, and transmit (TX) to the network, without worrying about any ACK’s (UDP only remember)

This means that you only use one fiber connection for a connection to an X4500 and the network, as you hook the TX of the X4500 upto the RX of Fiber XFP1 on the streamstar switch (for example) and then the TX of XFP1 to the providers network fabric! This allows for a much better utilization of your fiber network adapters.) … Anyway, back to the streamstar switch itself!

To do this for so many streams, the streamstar switch needs a lot of quick to access memory, and it definitely has that! the system is built in a vertical blade chassis, with each blade having 64 standard Dimm slots (Plus an individual network processor per board to tag the packets etc) This allows for upto 1TB of RAM per streamstar switch! (using 2Gb Dimm’s)

This system is definitely aimed at high uptime in a busy environment too, with each system having multiple redundant PSU’s, easily replaceable (mainly hot swappable) components, and the ease at which the interface allows for failover nodes to be set up.

I have spend nearly a week with this piece of kit, helping some of the designers / engineers who worked on creating the system set it up, and im VERY impressed! sun really seems to be keeping it coming with a great lineup of products! long may it continue!

I’ll let you know more about the management of the system when I have had a peek around it’s interfaces!

//Matt

(I feel I need to say here, just to cover all bases, that this post reflects my own opinions of this product and it’s setup, and what I have written here (apart from the quote directly from the sun website) should in no way be taken as the views of Sun Microsystems inc or its affiliates)

For more reading on this product have a wander over too: http://www.sun.com/servers/networking/streamingsystem/