CoDNS: Masking DNS Delays via Cooperative Lookups
The Domain Name System (DNS) is a ubiquitous part of everyday
computing, translating human-friendly machine names to numeric IP
addresses. With its redundant design, aggressive caching, and
widely-assumed reliability, few suspect its internal failures as a
source of delays. We show, through careful measurement, that the
infrastructure responsible for resolving DNS names often encounters
various failures which then induce delays. A systematic examination of
the problem shows that the failures are widespread, uncorrelated, and
can be a significant source of DNS-related delays.
We address this problem via the development of CoDNS, a cooperative
DNS lookup service. It uses a locality and proximity-aware
design to achieve low-latency, low-overhead name resolution in the
presence of local DNS nameserver delay/failure. We show via repeated
measurement and live traffic that CoDNS is an effective solution to
DNS problems, and eliminates a major source of delay.