Here is some additional information to supplement Greg's post. I had the same question this week from a Pacific northwest university so this must be Free/Busy week.
Here are the prerequisites required for this to work:
1. Representation of the target user contact objects in the source Exchange org directory. This can be either from CSV imports or some other sync mechanism such as using ILM 2007 FP1.
2. Add an availability space for the target SMTP domain. From the Exchange shell run: Add-AvailabilityAddressSpace task. You can find more information here about that task.
How does this actually work between Exchange 2007 organizations?
1. User performs a free/busy lookup for a user that is not in the same Exchange 2007 organization by selecting their contact. 2. The Availability Service finds the availability space for that SMTP domain space via the autodiscover SRV record in DNS. 3. Availability services talks to the target domain's AutoDiscover service to determine the Availability Service URL responsible for the target mailbox. 4. Either source user's credentials are used (trust scenario) or a free/busy account's credentials are used (non-trust scenario) to perform the F/B lookup.
How granular can this cross-org calendar information be?
It depends on whether the Exchange 2007 Org you are trying to retrieve availability information from is a trusted Forest or an untrusted Forest. If it is trusted Forest, the per user permissions will apply as to what can be viewed. If it is an untrusted Forest, a service account must be used and only the Free/Busy information can retrieved.
How do I set the cross org service account when no trust exists?
On the target CAS server Org, use the set-availabilityconfig command. See here for more information.
Here is an example using a local forest based free/busy account. This account should not be a mailbox or any type of elevated privileged account:
set-availabilityconfig -orgwideaccount "schooldomain\orgfbacct"
On the source CAS sever Org, use the Add-AvailabilityAddressSpace command. See here for more information.
Here is an example using the remote forest credentials you added above.
You should see something like this:
That is it. Test it out.
Note: If you want this cross-org availability lookup to work over the Internet, make sure you have a CNAME record on your external DNS servers configured such as autodiscover.school.edu pointing to your CAS server or loadbalanced VIP name.
The Dean of XYZ on Main Campus needs to be able to setup meetings with the Dean from XYZ at the Medical School. Sounds easy. Well, the Main Campus has one forest and the Medical School has another forest and neither are trusted. In earlier Exchange versions this could be very difficult. In Exchange 2007 this can be "Easy" to setup. I laugh when I hear Easy because I was a consultant and Easy usually tacked on time to my engagement. In Exchange 2007 calendar information is shared via a web service called the Availability Service. The Availability service improves information workers' free/busy data by providing secure, consistent, and up-to-date free/busy information to computers that are running Microsoft Office Outlook 2007.
In cross-forest topologies where all connecting client computers are running Outlook 2007, the Availability service is the only method of retrieving free/busy data.
You can use the Availability service in cross-forest topologies across trusted or untrusted forests. If trusted the information can be per-user and if untrusted as the case with alot of Universities the information provided is the default free/busy to the other forest.
The type of free/busy information is determined by whether the cross-forest free/busy data is configured as a per-user or an organization-wide service. Per-user free/busy information is possible only in a trusted cross-forest topology and makes it possible for the Availability service to make cross-forest requests on behalf of a particular user. This also allows a user in a remote forest to grant detailed free/busy information to a cross-forest user.
However, with organization-wide free/busy data, the Availability service can make cross-forest requests only on behalf of a particular organization. With organization-wide free/busy data, a user's default free/busy information is returned, and it is not possible to control the level of free/busy information that is returned to users in the other forest.
To understand the objects in both forest it is necessary to use GALSync to synchronize the user objects between forest. Also, if you have clients older than Outlook 2007 you need to use the InterOrg Repl tool. Microsoft Exchange Server Inter-Organization Replication.
Permissions needed for cmds:
Get-ClientAccessServer - Exchange View-only admin
Add-ADPermission - Exchange Org Admin
Add-AvailabilityAddressSpace - Exchange Org Admin
Set-AvailabilityConfig - Exchange Org Admin
How to do it? (untrusted only)
1. On CAS in Target forest:
2. Run the following commands to add the Availability address space configuration object for the source forest
$a = get-credential (Enter the credentials for organization-wide user in Contoso.com domain) Add-AvailabilityAddressspace -Forestname Contoso.com -Accessmethod OrgWideFB -Credential:$a
For full details on untrusted and trusted configuration see http://technet.microsoft.com/en-us/library/bb125182(EXCHG.80).aspx
One of my HiED customers asked me the other day about SPAM coming from within campus going to the Internet. Sites blacklisting you because it appears that SPAM was coming from your domain or even your address. Check out this blog on how to prevent this:
http://exchangepedia.com/blog/2008/09/how-to-prevent-annoying-spam-from-your.html
I had this question from a university in the rocky mountain range. With Exchange Server 2007 unified messaging, the UM server can directly detect a fax tone using the T.38 FOIP (Fax Over IP) standard and route inbound faxes to an extension. It does not provide the ability to send faxes outbound. For outbound faxing, it is required to use a 3rd party Fax software product.
How can I configure the fax extension?
The fax extension can either be a dedicated fax mailbox, the same extension as the users mailbox or a separate extension paired to the user's mailbox.
What does the inbound fax flow look like?:
The inbound fax hits the IPPBX or PBX and the signal is translated to T.38 (FOIP) directly or through the SIP GW. The Exchange UM server is listening for the T.38 tone. Once the UM server detects the T.38 tone, the fax is converted to .TIF on the UM server. Next, the UM server performs an AD lookup for the extension, routes the fax message to the Hub Transport which routes it to the correct the mailbox server.
Does this require a fax card to work?
There is no additional fax HW required for this to work.
How does inbound fax work if I am voice enabled with OCS?
The OCS Mediation Server currently does not understand the T.38 FOIP standard therefore you must create a separate extension and route fax extensions directly to the UM server versus through the Mediation Server. Click here for more information.
What does the fax look like?
Similar to a voicemail, the fax arrives as a .TIF attachment in your Outlook, OWA or Activesync mobile device inbox. Here is a sample fax in Outlook:
Does this require Windows Server 2008 fax services and do they integrate?
No, it does not require Windows Server 2008 fax services and they are not integrated at this time. For more on Windows Server 2008 fax services see here.
The Edge Planning Tool asks questions about your proposed or current edge server deployment. The tool uses your answers and Microsoft Office Communications Server 2007 best practices to generate the following reports:
http://www.microsoft.com/downloads/details.aspx?FamilyID=149e5dd5-eaae-46b6-afba-01c31e88a275&displaylang=en
After answering all the questions the tool gives you a series of reports.
Here's an example of one report. This one documents all settings for FQDN for internal/external edge of A/V and Access Edge/Web Conf Edge Servers, DNS, Certificates and Firewall Rules. Very cool tool.
A customer asked me yesterday about pre-staging clients with contacts. They were looking to add staff/faculty groups and contacts to Office Communicator. I knew this could be done from the OCS 2007 Resource Kit via WBEM (LCSAddContacts.wsf) but after a quick Live Search I found a MMC snap-in created by Egypt Network called OCSCM. www.ocscm.com The tool is free and in Beta but the results have been good so far. It allows you to create OCS users, assign contact list to OCS users, add/delete groups, delete OCS users, and Move OCS users from one group to another.
What I was most interested in was the ability to create groups and populate them. So I enabled a few new users in my environment to start with.
Next I installed the MMC Snap-in on my OCS Server and fired it up. The first Item on the agenda was creating new groups. I created a new group called "IT Group". I know - very original. Next I looked for Unassigned users. My new user was available as I hadn't assigned any groups to the user.
I selected Bill Hagen and assigned him to the IT Group.
I can then review the IT Group and make changes but when the address book is sync'd. abserver.exe -syncnow. I launched Office Communicator with the below results!!
I had this question from a large school district down in Florida and the answer is it depends on what aspects of the OCS conference you are using.
Here is a bandwidth breakout of the conference scenarios:
Application Sharing bandwidth:
Peak Bandwidth Measured in Application Sharing changes as available bandwidth changes.
Desktop Sharing and Remote Control bandwidth
Almost the exact same bandwidth requirements as Application Sharing.
VOIP audio conferencing bandwidth
50Kbps to 80Kbps per audio session minimum required
Webcam or RoundTable video bandwidth
Basic webcam 50Kbps minimum to 350Kbps maximum per video session
RoundTable panoramic video doubles this requirement to 100Kbps minimum to 700Kbps maximum per video session.
Recording Playback
To view a previously recorded Live Meeting session from a server is around 220Kbps.
Whiteboard and Poll sessions
Very light weight bandwidth requirements
For more information see this whitepaper here.
Other customer questions:
What are the correct antivirus exclusions required for OCS?
I have only seen information around excluding the OCS binaries and databases from antivirus tools.
What do I need to have installed in order to create my databases on a remote SQL server? Do they need to be installed on my OCS server?
You must install the Backward Compatibility Tools on the OCS server in order to instantiate the pool and create the OCS DBs on a remote SQL server. You can download the tools from here.
Will OCS run on 64-bit Windows Server 2003?
OCS 2007 RTM is not supported on a 64-bit Windows Server 2003 or Windows Server 2008. This will change with OCS 2007 R2 as it will be moving to 64-bit only support. More to come in future blogs around this. Here is the official OCS team blog about the switch to 64-bit only OCS.
Will OCS run on Windows Server 2008?
OCS 2007 RTM it is not supported to run on the Windows Server 2008 operating system. This is slated to change with OCS 2007 R2. More to come in future blogs around this.
Can SQL 2005 be 64-bit?
Yes, in fact it is preferred to run SQL 2005 64-bit.
Will OCS run with Windows Server 2008 Active Directory?
Yes, OCS is supported running in a domain that contains Windows Server 2008 domain controllers.