i have the following Szenario. 2 Origin-Servers (i7-4770 and Xeon E5-1650 running under Win2k12 R2 Standard), one as Primary Origin and the second as Backup Origin. Both with a 1Gbps Network-Connection. 4 Edge-Servers to serve the Stream to Viewers in different Datacenters. All Edges are Intel Quadcores (Xeon E3-1230 with 8-16GB RAM an 10Gbps Network-Connection). Each Edge has a configured Limit of 1500 simultan Player-Connections. The general Config is a classic Origin-Edge Config with Loadbalancer on the Origins and runs fine. All Servers run with the newest Wowza 4.1.2 Monthly Edition. All incoming Streams has a Resolution of 720p25 and 2-3 MBit Bitrate. Transcoder does also run and transrate a Single 360p (800Kbit Bitrate) Stream from all incoming Streams.
Now we will reach more Viewers worldwide. Also the Stability auf our System is partial a Problem, during temporarily Routing Problems between the Orgin and Edges in Germany. So we plan to restream to the Leaseweb CDN. We have a 30-Day Test-Account to test the Leasweb-System. But i am not sure about the right Settings in Wozwa an in the Control Panel of Leaseweb CDN.
On my Origins, i have a Live-Application. To this Live-Application, we send our Encoder-Signals. On the second Origin i have also configured a Live HTTP Origin Application. Further i have configured some .stream Files on the second Origin. This .stream Files do a restreaming from the Live Application on Origin 1 to the Origin 2 Live HTTP Origin Application (Appname: livecache). I have added the .stream Files to Startup Streams an make a connection to livecache App as Livestream Repeater. So we can run our old Edge System and also the new connection to the CDN simultan. The Origin 2 is actual configured to serve only for CDN. I hope this Configuration is possible? At the Moment, it runs fine.
Now i can make Settings for restreaming to the Leaseweb CDN. In the Control Panel of Leaseweb CDN, i have configured 2 Pull-Zones für HTTP-Livestreaming. 2 Subdomains, forwarded via CNAME Entry to the CDN. This Configuration is ok and runs. Further i can set an Cache Settings in the Control Panel, and at this Point i am not sure about the right Settings. See the Screenshot:
On my Origin 2, Wowza Live HTTP App is configured like this:
Leaseweb itself is not a great Help to make any Settings. A Leaseweb Technical wrote to me:
What does he mean? Cache Settings on Wowza or Cache Settings on Leaseweb CDN? On the Leaseweb CDN i can overwrite the Cache Settings of Wowza. See Screenshot, Ignore Origin Cache Control to Active and Cache-control Header to 5 Minutes. My Wowza itself is configured like the Screenshot to max-age=300 (like 300 Seconds = 5 Minutes).Regarding Live Streaming there are some limitations. Because the ‘playlist.m3u8’ is dynamically generated, we will not cache this object for longer than 1 second.
This means that most of the viewers/clients will fetch the ‘playlist.m3u8’ from the origin server (through the CDN).
However, the files that generate the most bandwidth are MediaChunks (.ts files). These are cached on our platform. But since we have multiple nodes servering the content, we could make up to 20 connection to the origin server to fetch each file.
The customer needs to make sure that the caching headers configured on his origin (wowza) server have the correct settings. Because if he sets the header to ‘no-cache’ we will not cache the objects. A recommended cache time for MediaChunks with Live Streaming is about 5 minutes.
Has anyone suggestions about the right Configuration for me??
Leaseweb also tells me that the CDN can make up to 20 Connections for each Stream to the Origin to fetch the Chunks. So i calculate this ...
- 1 Stream 720p = 2,5 MBit Bandwidth x 20 Connections = 50 MBit Bandwidth
- 1 Stream 360p = 800Kbits Bandwitdh x 20 Connections = 17 MBit Bandwidth
So i have round about 70-80 MBit Bandwidth for 1 Stream including the transcoded 360p Stream.
Currently, we have up to 4 incoming Streams simultan. So i must calculate with up to 280 - 320 MBit needed Bandwidth for all Streams. Is this a correct calculation?