For those who might have confronted the problem of dealing with the provisioning of applications across WAN links hosted out of central / single instances data center, far away from the primary user base, would know that provisioning of GbE or investing in LAN technologies / superdome servers exclusively, doesn't make much sense anymore.
With an upcoming proposal to host a single instance ERP systems out of a datacenter in an asian country, I am confronted with the same problem. I do understand that WAN optimisers, application load balancers coupled with suffcient bandwidths & a 24/7 network operations center to cater for my 10,000 odd user base, apread across different parts of the world, are a given.
Is a single instance model of an ERP ( as proposed by our SIs) the best design? To me, even though hosted in our own datacenter this would be just a simulation of cloud computng architecture.
Can the instances be spread across various countries to enhance user experience and increase app response times? I am a bit worried that 'change management' of users who currently access the legacy ERP application over the LAN bandwidths of a giga range, would not be an easy process and I need to technically design the most efficient app delivery process across the WAN links, as possible.