OWA for remote roaming users? 1

[rpast]

Hello all -
I have a simple question, which surprisingly I can find no information for. In planning the migration from Exchange Server 5.5 to 2003, I'd like to consolidate our sites and centralize all servers at headquarters, as Microsoft recommends in cases like ours -- 3 locations throughout country, 50-150 users at each. The plan is to use cached mode for users at all sites with dedicated systems - also recommended.

At all locations we also have a fair amount of users with roaming profiles. Some of the shared PCs have 20 to 30 users logging on regularly. I've read Microsoft's suggestion that these users store their Outlook info on the Exchange Server instead of in PSTs, and not to use Cached-mode, since the OSTs do not roam, and multiple OSTs will be created on the various PCs a user logs onto.

This is all fine for our roaming users at headquarters where the Exchange Servers will be. But what about those roaming users working at the other facilities? Our WAN speed is adequate for many things, but downloading a mailbox every time a user logs on is not one of them. I'm thinking the logical answer is to have them use OWA, as our remote user vpn-ers will do - in this case, redirecting their OWA requests to the Internet. But nowhere have I seen this recommended as a best practice.

Any comments? Thanks.

 

[sab4you]

The problem of having them just use OWA - is that they no longer can have their own PST files.

So if you have mailbox limits, they can potentially reach these limits and be SOL.

I have not used this, but you may want to investigate the new feature in Exchange 2003 of RPC over HTTP. This would allow users to use Outlook as a client and enable you to use its cached mode and PSTs i think...

 

[rpast]

Thank you. I'll look further into this and report back.

 

[rpast]

My conclusion re: this is that RPC over HTTP is just a slow Outlook client connection. If our remote roaming users complain too much about OWA, I'll probably just have them use cache-mode over the wan link, despite Microsoft's recommendations. Overall, I found very little written about RPC over HTTP.

 

[ShackDaddy]

Do you think that you would generate more traffic from your remote offices NOT using cached mode than you would downloading the mailbox each time a new user/pc combo comes into the mix? You might initially try not using cached mode for the remote sites for a while (assuming your WAN links are usually reliable) and get an idea what the performance impact is like. If things are too sluggish, start switching to cached mode and see what the relative impact of the mailbox download is like.

RPC over HTTP is for use over the public internet. It's not really a good alternative for access within the corporate LAN unless you want to heavily restrict the ports allowed, and I wouldn't think you'd want to lock things down to HTTP.

ShackDaddy

 

[rpast]

Thanks for the response. Admittedly I’ve been assuming that not using cache-mode would be really slow over the wan. But you have an interesting idea – it would solve the problem of multiple caches on the shared PCs. As it is, if the non-cache-mode does prove unbearably slow, I’m still leaning towards OWA, only to keep from having upwards of 30 caches on some of the shared boxes and maybe having the cache roam around with the users in their profiles (actually, not sure whether the cache roams),

Given this, if the users bark at OWA, I might still consider RPC over HTTP over the public Internet, which is touted as faster than going over a vpn. Apparently, only SSL needs to be poked into the far firewall. Who knows, maybe this would be a better option for the remote non-roaming users as well, saving our wan for other traffic (cache-mode can be used with RPC over HTTP too). But this is all guessing. Time to download a trial version and test some things.

By the way, your point about RPC over HTTP as meant for use over the public Internet makes me point out that I’m only thinking of both OWA and RPC over HTTP as accessing over the Internet, bypassing the wan. Some hands-on might reveal this as a stupid question, but is it feasible/common to use OWA just within the corporate network?

 

[ShackDaddy]

At my office employees use OWA internally when they aren't at their own desks. We do that rather than use roaming profiles.

RPC over HTTP is faster than standard RPC access over a VPN, but I'd hazard that it's less secure too. My personal favorite technique is to set up terminal servers with all the "local" apps running on them for our remote users to use, but that's probably not something you want to do with whole remote offices, but just for telecommuters.

ShackDaddy

 

[rpast]

Lots of options. Thanks.