Software

Ask something
Discussion Locked

Outlook With Exchange Server

0 helpful
8 replies

by woody h

Closed to new repliesThis discussion is closed. It stays readable, but it takes no new replies.

We are currently in a heated discussion on whether to implement Outlook with the exchange service and .pst files and go corporate, or to implement it with IMAP. We have 1 exchange server that sits at headquarters in FL. We have outlying offices inserveral different states that all have dedicated circuits to headquarters. The speeds range from 256KB to T1. I understand that with IMAP all info is stored on the server until someone reads their email or d/ls an attachment. With corporate and .pst files, the email is d/l'd right away. Now, question is, with the exchange service, does that maintain a continuous connection with the exchange server? What about IMAP, if you leave outlook open, does that maintain a continuous connection withthe exchange server. We are looking for the lowest bandwidth usage possible. If outlook with exchange service does maintain a continuous connection, is there a way around it? I would love to go to corporate so that everyone can use the global address list. Any and all help is appreciated.

Woody

8 replies

by gigelul

Outlook with exchange scenario: client is not on line. Client check at preset time for news/e-mail.
About IMAP: I don't use it.
I think that in both scenario you can set a period of time for synchronization.
The problem is amounth of data which will be transfered.

by brasslet

While bandwidth is an important consideration, there are other reasons to pick one client protocol over another.

POP3 downloads the client?s messages to the workstation, where the mail is viewed offline. Since the connection to the server is only maintained while messages download, POP3 might be a good choice for unreliable networks. In addition, because mail is taken off the server, the server-side requirements for disk space are lower than for other clients. But there are several negatives to using POP3. If your users depend on keeping their e-mail long-term, they need to backup their workstations since that is where the mail is stored. POP3 also only gives access to the user?s Inbox; other folders are not accessible.

IMAP is an improvement over simple POP3 in a few areas. IMAP can keep the messages on the server, yet manipulate them as if they were local. IMAP can also download headers only, further reducing bandwidth requirements, or it can download entire messages as POP3does. It also allows for access to folders other than the Inbox. If I had to choose between supporting POP3 or IMAP, I?d pick IMAP for these reasons.

Neither of these choices provides the functionality of a MAPI client. You?ll need to publish LDAP to lookup addresses. You?ll also need to workaround calendar issues, and you can?t effectively use Public folders. Why run Exchange if all you use is such a limited set of its capabilities?

by brasslet

Another option you didn?t mention is OWA, which might be a good compromise. Its bandwidth requirements are lower than MAPI (as long as the OWA server is on the far side of the WAN connection). While it can?t do everything a full MAPI client can, it?s a lot better than IMAP4 or POP3.

Another possibility ? use Terminal Service clients to run Outlook off a Win2K server with Terminal Services. This works great, even on very low-bandwidth connections.

A full MAPI client (Outlook) will use more bandwidth than any of the above. Despite the first poster?s assertion that the client is ?not online?, MAPI establishes an RPC to the server while it?s connected that consumes bandwidth as long as Outlook is open. Newer versions supposedly are less?chatty? but still require reasonable bandwidth to operate properly. I can?t tell you for sure how big the pipe needs to be, because good performance depends on how much bandwidth is available to the client rather than how much total bandwidth you?ve purchased. A clogged T1 may not work as well as a lightly used 128k frame connection, for example.

P.S. Even if you go with MAPI clients, try to avoid .pst files. Why use them?

by vigo98

I think that the only reason to have Exchnage at all is the ability to use the full Outlook client. When used in such way it becomes a true Server/Client application that gives you the best of both worlds: low bandwith consumption and advanced item manipulation features.
I would deffenetly suggest using full outlook client and enabling .ost files(offline storage). This will allow those users who do need permanent access to their email to download the messages only once and access them from thelocal disk in future.
In addition to that, Outlook exchnage client is very tollerant to lost connections or slowdowns. It will just give a worning "delay" message. Once the connection is restored the client continues functioning like nothing happend.
Please put your comments if you need more practical info on how to implement what I have described.
Victor

This discussion is closed to new replies.