bgp4cast - management of large IP traffic volumes by commercial criteria
bgp4cast is a working concept (currently beta-testing) for distributed content servers with large IP traffic volumes. These so called "server cluster" could contain ftp download areas or streaming media like shoutcast or icecast radio streams.
bgp4cast allows the system administrator to redirect his clients to the nearest or cheapest server. As the name says, decision rules are BGP4 driven, which allows forcasting traffic and cost of bandwidth. bgp4cast allows realtime automatic updates helping to reduce manual administration significantly. This is especially useful for large volumes with small budgets like webcasting.
bgp4cast is using open source software like Zebra / Quagga, Netfilter (iptables), Apache, Perl and should work with any flavor of Linux or Unix. The concept itself is not available freely as it's not only a piece of software. For implementation, among connectivity to Internet Exchanges and the operation of an autonomous system, one must be able to handle the various techniques of tagging and filtering BGP4, otherwise bgp4cast doesn't make sense.
Init Seven AG, who invented bgp4cast, offers the operation of bgp4cast-driven server cluster environments. If you have a small budget but huge need of bandwith as your content is very popular, bgp4cast might help to optimise your traffic cost significantly by keeping traffic local. We consider a cut down of bandwidth cost to 1/3 possible.
It's not required that a customer has all his download servers operated by Init Seven AG, but the addition of one or more bgp4cast servers can add significant bandwith portions to the whole download environment for a rather small per-MBps price.
If you like to get an offer for bgp4cast services, please contact us by email, describing your application, needs, if possible geographical spreading of your clients and the required bandwidth. Please note that bandwidth requirements below 50 MBps (except Shoutcast / Icecast streaming) commonly is not worth the implementation of bgp4cast.
How bgp4cast works:
Think of a server cluster built with 4 servers serving the same content, like a FTP download area or a Shoutcast radio stream. These 4 servers are geographically dispersed. One is directly connected to AMS-IX Amsterdam Internet Exchange, one to DE-CIX Frankfurt Internet Exchange, one to NYIIX New York Internet Exchange, and one is located in a colocation in Switzerland. The latter is the main server of the content.
A client connects to the content website, showing general information. By clicking the 'download' or 'listen now' button, the request is sent to the server at AMS-IX. This server checks the IP address of the client. If the IP address is learned locally from AMS-IX peers, the client is granted to connect, otherwise he gets redirected to the DE-CIX server.
The DE-CIX server checks again the IP address of the client against the locally learned routes from DE-CIX peers. As DE-CIX has different routes local than AMS-IX, other clients can connect. Again, if the client is local, he is granted, otherwise he gets redirected to the NYIIX server.
At NYIIX the same procedure happens again, and if the client is denied again, he finally gets redirected to the main server, who allows any client. The whole procedure takes only a few milliseconds up to a few seconds, and is transparent to the client.
This procedure allows to send the clients to the most local server, which allows to handle large volumes of traffic locally, reducing international bandwidth costs.
