Tonight one of the regular update emails arrived from OpenDNS, I signed up with them years ago and have used their service on and off over time.
The OpenDNS new Family Shield option looks interesting for those of you looking for options while we wait for the great Internet fillter of Australia!
I thought I’d check out their DNS resolution again, just to see if things have improved, in the past it’s been pretty average for those of us in Australia.
One of the sites I often frequent is the ABC website, mainly the news section or sometimes the kids games if Luca is around 🙂 So let’s take closer look.
OpenDNS lookup for www.abc.net.au
;; ANSWER SECTION:
www.abc.net.au.      0   IN   CNAME   www.abc.net.au.edgesuite.net.
www.abc.net.au.edgesuite.net. 0Â Â Â INÂ Â Â CNAMEÂ Â Â a1632.g.akamai.net.
a1632.g.akamai.net.   4   IN   A   65.200.11.152
a1632.g.akamai.net.   4   IN   A   65.200.11.145
;; Query time: 216 msec
;; SERVER: 208.67.222.222#53(208.67.222.222)
The first issue I note is that the closest OpenDNS resolver to us is in LA, hence each lookup inherits the latency across the ocean and sits at over 200ms response time.
The second issue is that the ABC website is in the main hosted on the Akamai CDN, in this case the OpenDNS lookup has directed me to an Akamai host also in LA, also over 200ms away from me.
How does this compare to using the DNS resolvers provided by Internode, Australian ISP of choice? 😉
Internode lookup for www.abc.net.au
;; ANSWER SECTION:
www.abc.net.au.      0   IN   CNAME   www.abc.net.au.edgesuite.net.
www.abc.net.au.edgesuite.net. 0Â Â Â INÂ Â Â CNAMEÂ Â Â a1632.g.akamai.net.
a1632.g.akamai.net.   12   IN   A   150.101.98.80
a1632.g.akamai.net.   12   IN   A   150.101.98.86
;; Query time: 15 msec
;; SERVER: 192.231.203.132#53(192.231.203.132)
The Internode resolver response time is mssively quicker than OpenDNS, most of the 15ms it takes to respond is made up of the latency on my DSL line which is usually in the 10 to 15ms region.
Additionally the Internode DNS resolver as directed me to an Akamai CDN node that’s on the Internode network and again is in the same state as myself, meaning it’s also only 15ms away. Once again that’s just the latency of my ADSL service.
Internode has DNS resolvers and Akamai CDN nodes distributed around Australia, so it may vary slightly for your connection, but in this case using my ISP’s DNS resolver results in vastly superior performance and response.
As an aside I checked against Google’s DNS resolver 8.8.8.8, the query time response was on par with OpenDNS at 220ms however it directed me to an Akamai CDN node in Malaysia, while geographically closer to Australia than the US West coast, it’s actually even further away latency wise at 260ms.
So what’s the harm in using OpenDNS? Performance, that’s what gets harmed! Currently the OpenDNS performance in Australia is pretty awful if your ISP runs decent DNS resolvers and hosts Akamai CDN nodes.
