Topology of the network

From Giss
Revision as of 20:21, 3 June 2008 by Sevy (talk | contribs)

Context And Goals

This tasks is intended to address and fix some problems inherents to GISS 2.0 which is based on a centralized topology with one central access point, the master server ( giss.tv ). This topology was leading sometimes to a saturation of the system as all the sources could only emit to the central server which upload bandwidth is limited and sometimes got saturated.

Work achieved

Upgrade of servers

First, before changing the topology, we started by upgrading our servers to make all software servers coherent. The main server has also been migrated to a more powerful machine ( courtesy of hangar.org ). After the cleaning up of the servers, we reached this configuration :

List of servers before reconfiguration
Name Location Icecast Version Mode
giss.tv Paris, France Icecast 2.3-kh34a Primary
stream.r23.cc Bergen, Norway Icecast 2.3-kh34a Relay
thescreen.tv Vienna, Austria Icecast 2.3-kh33 Relay
whitmanlocalreport.net New York, USA Icecast 2.3.1 Relay
live1.radiovague.com San Antonio, USA Icecast 2.3-kh33 Relay
live2.radiovague.com San Antonio, USA Icecast 2.3-kh20 Relay
stream.goto10.org Amsterdam, Netherlands Icecast 2.3-kh33 Relay
labbs.net Malmö, Sweden Icecast 2.3-kh20 Relay
stream.horitzo.tv Berlin, Germany Icecast 2.3-kh20 Standalone


As you can see, we had one primary server and 7 relays, stream.horitzo.tv is a standalone server but all its activity appears in the map also.


Setting up a secondary server

When a clean list of servers has been established, we installed one of them as a secondary server by doing a database link between the primary and the secondary server, this means that all mountpoints created on the primary server ( giss.tv ) are now also known of the secondary server and thus, a source can emit to a server or the other one.

The database link is a scheduled task that updates mountpoints both on the primary and secondary servers.

Technical Details

Topology of GISS 2.0

Server-topo-before.png

This configuration is based on a central server receiving all incoming streams and relaying it to other servers "on demand". A client/listener can be served by the main server or by a relay when the master server has reached the maximum number of listeners on a mountpoint. In the actual configuration, the maximum number of listeners for each stream is set to 10 ( for virtually 300 streams ).

New Topology of GISS 3.0

Server-topo-after.png

After the reconfiguration, each source has the option to emit to the secondary server, and a stream can be served by the primary, the secondary or one of the relay servers.

List of actual servers configuration

We just changed the mode of one of the servers so that it could be a secondary server, virtually we could have more secondary servers, but, for now, it seems to be sufficient for the upload trafic we get, considering also that the bandwidth of the main server has been increased, here is the grafic of daily traffic on the master server :

Giss-activity-0306.png

So, in the new configuration, each server has the following role :

List of servers after reconfiguration
Name Location Icecast Version Mode
giss.tv Paris, France Icecast 2.3-kh34a Primary
stream.r23.cc Bergen, Norway Icecast 2.3-kh34a Secondary
thescreen.tv Vienna, Austria Icecast 2.3-kh33 Relay
whitmanlocalreport.net New York, USA Icecast 2.3.1 Relay
live1.radiovague.com San Antonio, USA Icecast 2.3-kh33 Relay
live2.radiovague.com San Antonio, USA Icecast 2.3-kh20 Relay
stream.goto10.org Amsterdam, Netherlands Icecast 2.3-kh33 Relay
labbs.net Malmö, Sweden Icecast 2.3-kh20 Relay
stream.horitzo.tv Berlin, Germany Icecast 2.3-kh20 Standalone

Conclusion

This tasks has been completed and seems a very scalable solution. In case that the traffic would brutally increase ( after the workshop in india? ), it would be possible to mount more secondary servers and there's no more throttle in the system.