Since most CoDeeN sites are hosted at North American universities with Internet2 (I2) connectivity, one may suspect that low-congestion I2 peer links are responsible for our benefits. To address this issue, we pick non-I2 PlanetLab nodes and replay 10,792 unique lookups of hostnames from one day's live traffic on a CoDeeN proxy. Figure 16(a) shows that CoDNS provides similar benefit on 38 non-I2 nodes as well. The average response time in CoDNS ranges from 63ms to 350ms, while local DNS is 113ms to 1884ms, an improvement of factor of 1.64 to 9.52. Figure 16(b) shows that CoDNS greatly reduces the slow response portion as well - CoDNS generally spends less than 10% of the total time in this range, while local DNS still spends 32% to 90%.
(a) Average Response Time
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(b) Slow Response Time
Portion
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