DNS for Protocol Designers Presented by: Olafur Gumundsson, Peter Koch Sunday, July 31 at 15:00-17:00 =========================================== Various IETF working groups' protocols/applications have need for universal distribution of information related to their operation. The Domain Name System (DNS) is the natural fit to carry certain information. While the DNS is indeed a very valuable and powerful tool fulfilling its tasks very well for almost two decades now, it does not serve all proposed new uses equally well. And even if the DNS is the lookup system of choice, the extent to which the DNS is used still needs to be considered. Sometimes, the DNS's strength, its global availability, turns out to be a weakness when it comes to operational issues, tracking bugs and fighting misconceptions. This tutorial will cover DNS basics and how best to take advantage of DNS, as well as covering the pitfalls. We will cover in particular common misconceptions and design criteria to be used. Among the topics here are: o Wildcards o Sub typing o Additional-section processing rules o Unknown RR type support o Tree walking o ... The tutorial will not cover DNS server or resolver configuration, server operations or how to further develop or optimize the DNS protocol intrinsics. This tutorial will be most useful to those designing protocols in the applications area (i.e. wg chairs, document editors, design team members).