Below is the current Setup for exchange2010 1] Single forest single domain architecture. 2] 16 locations all over world . 3] Different location have mutiple smtp namespace ex: abcd.com xyz.com wer.com 4] Want to deploy exchange for mutiple location with different url's example uk http://webmail.company.com ,USA http://webmail.usa.com Main aim is to achieve exchange deployments at respective locations with different email address policy for different locations.HUB server for respective location's should send and receive mail from respective location. Can we have mutiple HUB Servers Internet Facing.

Yes you can have mutiple HUB Servers Internet Facing. But why you want to expose you HUB TS to internet, i hope you will be using any thrid party gateway or some sort of firewall. If not what about Edge servers??

You can have as many hub servers facing the internet as you like. Those servers can accept email for any server in the org and Exchange will deal with the routing. Email address per location - not a problem, but Exchange doesn't care about the location, and the AD site is not a value you can filter on. Therefore a lot of what you have outlined will come down to the design of AD, specifically: - configuration of Sites and Services - having the users in the correct OUs Then building filters in Exchange for the relevant OUs. Edge servers are a waste of money in my opinion. You might want to consider an antispam service which is location aware, or having a single point of entry in a data centre somewhere for all email, rather than having each server managing it. Finally ensure that you setup internal management policies so that org wide settings are applied in such a way that they do no cause a problem for the other parts of the business. Simon.Simon Butler, Exchange MVP Blog | Exchange Resources | In the UK? Hire Me.

Yes we have spam filters in each location for respective MX .Amit Shinde

Yes we have spam filters in each location for respective MX .Amit Shinde

Mangement want's Exchange CAS/NLB 2 DAG for respective location ( NO DR ) as users will try to pull mails from local exchange instead of Centralize exchange server Different locations will have different cas array ,DAG .OWA URL . Mailflow from respective locations will flow to respective locations smart host.