Author : Sivaprakash C 1
Date of Publication :30th November 2017
Abstract: The core of DNScup (DNS cache update protocol) uses a dynamic lease technique to keep track of the local DNS name servers whose clients are tightly coupled with an Internet server. DN2IP mapping change of the corresponding Internet server, its authoritative DNS name server proactively notifies these local DNS name servers still holding valid leases. Although the notification messages are carried by the User Datagram Protocol (UDP), the dynamic lease also minimizes storage overhead and communication overhead, making DNScup a lightweight and scalable solution. Based on client query rates (or service importance to their clients), it is the local DNS name servers themselves that decide on whether or not to apply for leases (or renewal) for an Internet service. On the other side, the authoritative DNS name server grants and maintains the leases for the DNS resource records of the Internet service the major components of the DNScup prototype include the detection module, the listening module, the notification module, and the lease-track file. DNScup achieves the strong cache consistency in DNS and significantly improves its availability, performance, and scalability.