Authority server selection in DNS caching resolvers

  • Authors:
  • Yingdi Yu;Duane Wessels;Matt Larson;Lixia Zhang

  • Affiliations:
  • University of California, Los Angeles, Los Angeles, California, USA;Verisign, Reston, Virginia, USA;Verisign, Reston, Virginia, USA;University of California, Los Angeles, Los Angeles, California, USA

  • Venue:
  • ACM SIGCOMM Computer Communication Review
  • Year:
  • 2012

Quantified Score

Hi-index 0.00

Visualization

Abstract

Operators of high-profile DNS zones utilize multiple authority servers for performance and robustness. We conducted a series of trace-driven measurements to understand how current caching resolver implementations distribute queries among a set of authority servers. Our results reveal areas for improvement in the ``apparently sound'' server selection schemes used by some popular implementations. In some cases, the selection schemes lead to sub-optimal behavior of caching resolvers, e.g. sending a significant amount of queries to unresponsive servers. We believe that most of these issues are caused by careless implementations, such as keeping decreasing a server's SRTT after the server has been selected, treating unresponsive servers as responsive ones, and using constant SRTT decaying factor. For the problems identified in this work, we recommended corresponding solutions.