A Web Based Solution to Replace Exchange?

benthemeek asks: "A friend of mine works for a company that has more than 6k users connecting to a Outlook exchange server instance through VPN from various homes all across the country. The executives at his company would like to move to Active Directory and a web based solution for these users. When Outlook Web Access was priced out, it was judged very expensive and they opened the floor to other options. They want a LDAP enabled, web based email and calendar that could hopefully plug in or replace Exchange, and if the solution can be load balanced between more than one server to ensure reliability and uptime, that would be even better. Slashdot readers come from many walks of life and I am sure some of you have gone through a similar experience and could give some insight to this problem. The fan boy in me would like to see a complete Open Source to meet this need, but that may not be possible. Have any of you done similar migrations, and to what solution did you go to?"

Comments

domino is still good

[khang]

sounds to me that you're running exchange 5.5 since you "would like to move to active directory"

i still think domino in the end is the best overall enterprise email system. it is a very good alternative to exchange and very scalable. you can easily put all 6k users on 2 boxes if you wanted to (i'd probably put them on 3 minimum though). in the long run it's cheaper than most solutions and requires very little administration. at least with domino you can get good 3rd party addons (blackberry, faxing etc). also the power of lotus notes databases. ibm isn't going anywhere soon either.

also their web mail works great, if you like you can use lotus notes or even outlook

if you wanted an a VPN replacement, either go the exchange route with RPC over http or get some SSLVPN solution.

Consider your options

[Deternal]

You want something standards compliant? Forget AD.

There are the following options:
IBM Lotus Domino:

1. standards compliant
2. ldap is build in
3. has integrated web access for all functions.
4. proven track record for stability
5. transactional loggin, combine with something like Tivoli Storage Manager and you have point in time recovery down to single e-mails
6. Domino is going with the stream - Exchange and Domino is about even in the corporate e-mail space
7. Quickplace and sametime add-ons for increased functionality such as voip, webcam and online conferencing
8. .
9. server runs on solaris, aix, linux, windows
10. client runs on windows, mac, version 8 supposed to run on linux
11. admin interface and domino web access runs thru firefox and IE

IBM Lotus Workplace

1. standards compliant
2. ldap is build in
3. Based on J2EE and websphere rather then NSF which Domino uses
4. build in OOo applet document editing
5. server runs on solaris, aix, linux, windows
6. client runs on windows, mac and linux

Sun messaging

1. comparable featureset to exchange
2. completely standards compliant

Open-xchange

1. foss
2. comparable featureset to exchange
3. standards compliant

The question is, do you only want mail and calendering? Then look at the last to, do you want a complete groupware/collaboration platform, choose one of the first too.

Skipping exchange makes sense, if for no other reason the roadmap/upgrade path and the draconian licensing scheme MS uses.