Efficient load balancing for bursty demand in web based application services via domain name services

In this paper, we propose an enhancement to the conventional Round Robin DNS load balancing technique which allows a single domain name to be associated with several web server IP addresses in a rotated order in a server cluster. Once the DNS server resolves the domain name to one of the web server IP address, the subsequent requests from the same client will be sent to the same server regardless of the current condition of the server. However, this conventional load balancing technique has a few disadvantages; Firstly, the DNS server is unaware of the status of web servers whether their services are available or not. Secondly, making changes to the DNS records can take days to propagate across the local DNS caches because the conventional DNS server will not delete their cached DNS records until the time to live (TTL) expires. Lastly, DNS server assumes all web application servers to have equal capability to offer their services without taking into account of the server's load and performance level. In this paper, a new approach is presented to enhance the DNS load balancing services to be more intelligent in load distribution. The DNS server is taking consideration of the status of the servers and will be distributing the services requests based on the performance matrix of the servers in the cluster.