geo dns

I was wondering what is a simplest way to do (geo) load balancing (gslb) (I'm not too concerned with fail-over or high availability, just latency)?

I don't want to simply do round robin dns or use sub-domains. I would like the users in Europe to be directed to the linode there and the ones in the US to be directed here for example.

I came across this link in the Linode library:

http://library.linode.com/networking/ns … tative-dns">http://library.linode.com/networking/nsd-authoritative-dns

But am not sure how this would work?

User -> User ISP -> Internet -> Linode DNS -> My Linode NSD ?

Or would the Linode DNS be out of the picture? What if My Linodde NSD is down?

Would running a NSD server solve this problem, or would I need to run PowerDNS for example?

If anyone has any information or has setup something similar in the past, please help! Any help or guidance is greatly appreciated.

Thanks in advance.