| dc.description.abstract | A structured approach to high availability and fault tolerance is essential
in a production-grade service delivery network, where delays and faults
can occur for a multitude of reasons. In this thesis, we consider the highlevel
scheduling and load sharing properties offered by the Domain Name
System, as implemented in popular DNS software packages. At this level,
the scheduling mechanism can account for server availability, geographical
proximity, time zones, etc. We explore the performance and capabilities of
high-level DNS-based load balancing, where we draw special attention to
the choice of caching policy (time-to-live) for DNS data. Our findings confirm
the high performance of modern DNS server implementations, but
question the use of DNS as a suitable load balancing mechanism in itself.
Further, we analyse the use of a database-supported DNS service for allowing
highly dynamical query responses, and show that this approach has
both potentially negative (single point of failure) and positive (improved
balancing flexibility) properties. | en_US |
