At present we have a number of sites in our exchange organisation. We us
VPN tunnels between most of our office due to the location of each making a
private network cost inefficient but we also have frame relay links between
some of the offices that are close together. We have a mixture of IMC
connections and MS exchange site connectors. The IMC connections between
sites are being gradually moved onto site connectors. We receive all mail
through a single line in one office which then directs the mail to the
correct mail server for that mail recipient through the site connector. We
schedule directory replication to happen at only specific times of the day
e.g evening and lunchtime to minimize the traffic. Because each of the
sites has it's own internet connection each site sends external mail through
it's own IMC to minimize mail traffic on the main SMTP server. The IMC
connector solution is easily setup but so is the site connector as long as
you fix and open the correct ports. I find monitoring the queues etc with
the site connectors easier and the solution slightly neater plus for
intersite connections it is supposed to be the fastest and least
complicated. I have had no really problems with the solution we have. As
long as you have a good reliable SMTP server on your main site preferably
with redundancy and a good ISP also with redundancy.
> I am looking for some good information regarding the best practice for
> connecting 3 Branches with a corporate Email Structure using Exch 5.5
> We currently have an Internet VPN using Cisco PIX's with full T1's at two
> the sites. We may decide to install a Frame Relay network between
> facilities and one central point for Internet Access company wide.
> Using the VPN, I believe it would be best to use the IMS as a site
> but what would be a good solution over a Frame config that would minimize
> bandwidth requirements of Exch replication.
> I would like as many real world cases as possible since some of this
> information may be used to back up my final solution.