1. King of Limitations Present by: Ao-Jan Su

2. Accuracy? Accuracy depends on the distance of end hosts and their authoritative name servers. Not true for “common users” (e.g. DSL, Cable and Dialup users) Routing paths between DNS servers may be different from the End-to-End hosts Accuracy can’t be improved!!

3. Availability? Incomplete!  at least 6% error messages! DNS servers of most large web sites don’t support recursive DNS lookup Limit the use of “server selection” The more King is used, the more likely it could be “banned” Recursive lookup is not “required” for a DNS server Network administrators would turn off this option when they see large DNS query traffic from outside Again, No way to improve!!

4. Other issues Not applicable to hosts behind NAT and Proxy Applications using King may overload the existing DNS servers and create application level latency

5. Why is it called “ King ” ?