The Domain Name System (DNS) is showing signs of strain. Attacks leveraging DNS protocols used to be fairly predictable and limited to the occasional DDoS floods. Now attackers use more than a dozen different ways to leverage DNS, including cache poisoning, tunneling and domain hijacking. DNS pioneer Paul Vixie has bemoaned the state of DNS and says that these attacks are just the tip of the iceberg. This is why you need to get more serious about protecting your DNS infrastructure and various vendors have products and services to help. You have four key options; here’s how to sort them out in a piece that I wrote for CSOonline..