OWA and ISA 2004

[Kevan]

We are migrating from Exchange 5.5 to Exchange 2003.

We have about 150 Users of which only 80 are in the main office and the rest
work from home/on the road. Many of them were useing OWA in Exchange 5.5 for
email.

In the new envoirnment we are considering putting an ISA 2004 server in our
DMZ and connecting this directly to our Exchange server on the Internal LAN.
(No Front End Exchange Server)

Is this option recomended from a security/performance perspective?

We do not really want the expense of an additional Front End Exchange server
if it is not really needed.

The alternative would be to use our Watchguard Firebox 1000 to NAT SSL
internet connections to a Front End Server on our internal LAN and do without
the ISA Server. We only have one spare machine to use for iether a ISA
implementation or a Front End Server.

Any advice/sugestions appreciated.

thank you.

Kevan

[Ben Winzenz [Exchange MVP]

With only 1 back-end server, there is no additional benefit of a Front-end
server except offloading *some* traffic. There certainly isn't any
difference security-wise, especially if you will be implementing an ISA
server. The only choice you need to make is if you want to use the
Forms-based auth feature of ISA, or if you simply want to publish OWA using
ISA. If you are trying to choose between a FE server and an ISA server, my
choice would be ISA as it has the capability to do lots of other things
besides just secure OWA publishing.

--
Ben Winzenz
Exchange MVP
MessageOne

[Tomcat]

With just a ISA 2004 server and a back-end 2K3 Exchange Cluster is it still possible to do Forms Based authentication?

I was told you couldn't utilize Forms based authentication with an Exchange Cluster.

Is it also possible to utilize RPC over HTTP without a Front End Server? I keep getting conflicting info that a FE is necessary for this.

[Edit] The last statement assumes the use of ISA 2004 as well.

Thanks!
Tomcat