On Tue, 15 Jan 2008, Eric Frazier wrote: Proximity checking is very important and I have run into cases as you have where it is needed. Even taking your example of a location in Toronto, peering arrangements would cause not all Toronto ISPs to act the same and therefore RTT could vary not just by 15ms but sometimes by 150ms. Now imagine I have a data center in Tokyo. Do I send all users from Hong Kong, Singapore, Korea, Taiwan and Australia to that data center in Tokyo or perhaps some would do better going to my data center in LA? In regards to the Neustar staticly defined IPs - I was only able to uncover that after digging. Thanks for the Netriplex lead. I like Neustar for their bullet proof DNS but not so much for their directional DNS service. -Hank
Hi Hank,
I am curious, what makes proximity checking so important? I am also curious about how you learned that UltraDNS uses a static list, even if it is a 'static' list it is updated frequently and likely only contains the kinds of errors that don't really affect you unless you have quite a few more than 4 locations. For example, if your locations in north america are Toronto, Seattle and DC, it doesn't matter too much if an IP in Atlanta is 90ms to DC AND 75ms to Toronto, but it would matter if you had three other data centers in the south to make that fine grained matching more worthwhile.
I know with Quova one of the first things I asked them about was the case of our own office IP which in their db returns Toronto and it kind of pissed me off that they couldn't see that the round trip time clearly showed this IP could not really be in Toronto, if you picked a few dozen known to 100% IP/locations and tested latency from those you could get a pretty good fudge factor to correct data or at least show it as being suspect.
Anyway, I have used UltraDNS in the past, there is also a company called Netriplex that is a newcomer in comparison, but their pricing is a lot better, not too cheap, not as expensive. They don't have as good as a network as UltraDNS either.
Eric Frazier Senior Architect 216 Main Street, Suite 312 Bathurst, NB, E2A 1A8 Canada Phone : +1 506 546 8292 Fax : +1 506 546 8092 -----Original Message----- From: owner-nanog@merit.edu [mailto:owner-nanog@merit.edu] On Behalf Of Hank Nussbacher Sent: Tuesday, January 15, 2008 7:21 AM To: jamie.baddeley@fx.net.nz Cc: nanog@merit.edu Subject: Re: Looking for geo-directional DNS service
At 12:14 AM 16-01-08 +1300, jamie baddeley wrote:
Yes, but that would require them to run a DNS server at each of their 4 locations. They do not want to run their own DNS. They want it outsourced.
Thanks, -Hank
Thought about anycasting? Broad as a barn door, but if you add health checking of the services and integrate that into what your DC router announces you get closer to what you want.
jamie
On Tue, 2008-01-15 at 12:55 +0200, Hank Nussbacher wrote:
I am looking for a commercial DNS service that provides geo-directionality. Suppose I have 4 data centers scattered thruout the world and want users to hit the closest data center based on proximity checks (pings, TTLs, latency, load, etc.). I know one can "roll their own", using various geo-locational data from companies like Maxmind. I am *not* interested in that. I am *not* interested in applicances like the Cisco ACE GSS 4400 either (that do this as well): http://www.cisco.com/en/US/products/hw/contnetw/ps4162/
What I am looking for is a commercial DNS service.
Is the Akamai Edgescape service the closest to what I want: http://www.akamai.com/html/technology/products/edgescape.html Is anyone using it? Can you recommend it?
Another service I know about is the Ultradns (now Neustar) Directional DNS: http://www.neustarultraservices.biz/solutions/directionaldns.html But this service is based on statically defined IP responses at each of their 14 sites so there is no proximity checking done.
Thanks, Hank