Wednesday, April 09, 2008

Load-balancing at Rogers

There is an interesting article in the networking magazine Network Computing of 1999 about Rogers' plans for the next few years. Concerned about the challenges that expected increases in traffic would bring, together with the expectation that e-commerce would become more important (making it all the more important that the traffic got through expeditiously), Rogers developed load-balancing technology to prevent server overload.  Some selected quotes:
    Ten Alteon Networks ACEswitch 180 server switches balance the traffic flows among Rogers' five Web and cache servers, as well as its VPN and firewall servers. The Gigabit Ethernet server switches redirect traffic when one server goes down or gets jammed with HTTP traffic. The switches also route and handle the packet filtering for Rogers' firewalls, and all of Rogers' servers are connected via Gigabit Ethernet.
    When a user requests Internet access, the switch directs that request to a proxy server. "It's load-sharing among cache proxies, and if they all aren't available, it then redirects the traffic to the Internet," rather than to the proxy server, Howell says.
This seems to be the explanation for the shifting IPs that we noticed earlier. Those shifts are taking place among various proxy servers.