Difference between an Exchange site and Active Directory site?

Exchange integrates with AD.  You would simply install Exchange 2003 per say on a windows 2003 server.  After you install the windows 2003 server you would install ASP, IIS, SMTP NNTP and any other protocols such as POP3 if you needed that.  Once that is done you just need to run the domain/forest prep so that exchange can integrate into AD.  After all this is done you install Exchange.  Pretty simple and straight forward from this point.  Once completed you can run Active Directory Users and Computers and right click a username/exchange tasks and create a mailbox.  Once this is done you  should be able to type http://servername/exchange and come up to a login box or simply login to Outlook Web Access provided you created a mailbox for the user you are logged in as.

Exchange is a collabertion and mail software package that is mainly used in a front end/back end or stand alone mail server.

This should give you a general idea and information on exchange.
http://www.microsoft.com/exchange/evaluation/overview/default.mspx

Is there anything in particular though you were wanting to know?

Kevin

Exchange 5.5 sites are similar to Active Directory sites.  They are an Administrative boundary and a routing boundary.  They can be connected with an X.400 connector or a site connector.

Exchange 2003 brings in the concept of an Administrative Group and a Routing Group, the Exchange 5.5 site being equvalent to the admin group.

Forgot to mention your Active Directory server is where you create all of your users, computers, Group Policy Objects, ADM Templates, security/distribution groups.  Exchange and Active Directory are usually on seperate servers for numerous reasons.

Kevin

http://www.exchangefaq.org/faq/Exchange-2003/Definitions/q/How-does-an-Exchange-5.5-site-compare-to-an-Exchange-2003-Routing-Group-or-Administrative-Group?/qid/1014

I remember reading somewhere that after Exchange 5.5, the Exchange site becomes one with AD. However, in Exchange 5.5, because it replicates by itself without the use of AD, it is a site of its own?? Am I correct on the latter statement?

Ok, that's true...so in a round about way AD sites can be tied into Exchange.  ;)

That was great. A well phrase direct answer. Thanks.

If you can be so kind and give a second opion in this question:

https://www.experts-exchange.com/questions/21484127/Exchange-5-5-W2k-Exchange-2003.html

Personally I would go with upgrading your NT4 environment to Active Directory.  It's a bit of a bear, but it doesn't hurt too bad.  Use an Exchange 2003 "swing" server to move the mailboxes to.  Move the resources (see KB 822931) and decom the 5.5 server.  Create the Exchange 2003 cluster and move the users back.
Note that a cluster can't run the RUS.

Yes, this will kill a few of your weekends.  I suggest purchasing a 5-call support pack from Microsoft, or getting the authorization to make a few calls ($245 each).  It used to be cheaper to buy a Technet Plus subscription since it included 2 calls and was $450, plus you got all of the Technet plus stuff.

BUT, if you are an EE premium member ($9.95 per month), you can ask all kinds of questions about upgrading to AD from NT4, upgrading 5.5 to 2003, ad nauseum.  The folks here are very helpful and compete for the points.

The Exchange 5.5 is required for the multi-million dollar system that depends on it. So, to answer, I wish I could upgrade, but there is no possible way at the moment.

All I wanted was to have another Exchange 2003 server that uses the same domain name to perform journaling. Nothing more.

That sucks...you have a multi-million dollar system which is reliant upon technology no logner officially supported by the vendor without support contracts.

Journaling on 5.5 might have to be your other option:
XADM: How to Enable Message Journaling in Exchange Server 5.5
http://support.microsoft.com/kb/239427