Managing Internet Calendar Sharing in Exchange Server 2010 Service Pack 1 (Part 1)

This article will cover one of the new features of Exchange Server 2010 which is the ability to Share and retrieve Calendar information with Internet Users.

Introduction

Exchange Server 2010 Service Pack 1 release brought a lot of new features to the table (by the way, this article is based on the Beta version available on the Internet) and in this article we will cover Internet Calendar Sharing with Internet users. Exchange Server 2010 RTM allows federated calendar between Exchange Server 2010 organizations (or at least an Exchange Server 2007 organization with an Exchange Server 2010 CAS just for Federation would work as well) where it increases the collaboration not just among users within the same organization but among different companies.

Now, Exchange Server 2010 SP1 goes beyond the company federation and allows end-users to share and retrieve calendars on the Internet in a secure and controlled way. There are two layers of security when we are talking about Calendar Sharing: the first layer is the organization level where the Exchange Administrator sets the boundaries for the Calendar Sharing; the second layer is at user level where the user can restrict a little bit more what was permitted at the Organization level. Users can easily go through OWA for instance and reduce the time window, the amount of information to be available, and their own calendar permissions. That is, either restricted or public available.

In order to provide Internet Calendar Sharing in Exchange Server 2010 Service Pack 1 and allow integration with common Internet calendars such as Live and Yahoo. Also, basing it on the iCalendar standards (RFC 2445), keep it secure and anonymous a new Virtual Directory was added to the current OWA structure, as shown in Figure 1. This new Virtual Directory has only Anonymous Authentication enabled and makes easier to an end-user to navigate in a Shared Calendar using the same Outlook Web App experience.

Figure 1

Managing Internet Calendar at Organization and CAS level

On the server side we have two different items to play with:

CAS Server and Organization configuration.

The first requirement is to enable and configure the external URL on your OWA Virtual Directory. In order to do that we can open Exchange Management Console, expand Microsoft Exchange On-Premises (<ServerName>), expand Server Configuration, and click on Client Access. Then, let’s select the desired Client Access server on the right panel, and double click on owa (Default Web Site) on the Outlook Web App tab.

In the General tab of the OWA properties, we can set the External URL by just typing in the information, as shown in Figure 2.

Figure 2

Note:
If for some reason you change your External URL you have to ask your users or at least create a script/cmdlet to stop and start publishing their calendar to get the new URLs.

The second phase of the Server level configuration will occur on the CAS Servers facing the internet where we must make sure that Internet Calendar Publishing is enabled. The attribute that we are looking for is the CalendarPublishingEnabled attribute, in order to have Internet Calendar functionality the value must be set to True. In order to retrieve the current value we can use several different ways, here we can see a couple of possible options:

To list the Calendar of all CAS Servers:
Get-OWAVirtualDirectory | Select Name, Server, Calendar*
To list the information from a specific server (Figure 3)
Get-OWAVirtualDirectory –Server <ServerName> | Select Name, Server, Calendar*

Figure 3
Now that we know how to list and validate if the server is correctly configured for Internet Calendar Sharing, we may have to enable the feature using the following options:

To change all servers:
Get-OWAVirtualDirectory | Set-OWAVirtualDirectory –CalendarPublishingEnabled:$true
To change a specific server specifying the server on the Set-OWAVirtualDirectory cmdlet
Set-OwaVirtualDirectory -Identity "<ServerName>\owa (Default Web Site)" -CalendarPublishingEnabled:$true
To change a specific server without specifying the ServerName\VirtualDirectory we could use the first cmdlet specifying the server in the first cmdlet to facilitate the process:
Get-OwaVirtualDirectory -Server <ServerName> | Set-OwaVirtualDirectory -CalendarPublishingEnabled:$true

The last step is to configure a Sharing Policy to allow Internet Sharing Calendar and define the level of information will be available to the end-users. The most important thing is that the domain must be set to Anonymous and any of these values for security are valid: Calendar Sharing with free/busy information only, Calendar sharing with free/busy information, plus subject and location, or Calendar sharing with free/busy information, plus subject and location and body.
We will be examining some examples of these three levels in a little bit.
The above explanation is shown in Figure 4, it does not matter if we are changing an existent policy or creating a new one from scratch but essentially the information entered will be similar to Figure 4.

Figure 4

Enabling Internet Calendar to all users

Now that we know how to configure the Sharing Policy in order to have Internet Calendar going, it’s time to demonstrate how to enable it to all users of your organization. The first step is to change the Default Sharing Policy. From the Exchange Management Console, follow these steps:

Open Exchange Management Console
Expand Microsoft Exchange On-Premises (<ServerName>)
Expand Organization Configuration
Click on Mailbox
Click on Sharing Policies tab
Double click on Default Sharing Policy
Select the existent Domain listed and click on Edit. Change the Domain to Anonymous and Action based on your requirements. Also make sure that Enable Sharing Policy setting is enabled, as shown in Figure 5.

Figure 5

Click on OK. You may receive a warning dialog box saying “Warning: You’re allowing users to access the feature that lets them publish their calendars. Make sure that the Calendar virtual directory has been enabled on the Client Access Servers so that published calendars will be accessible”, click OK.

It will work for all users that do not have any other Sharing Policy associated with their mailbox. By default all users are associated to the Default Sharing Policy, as shown in Figure 6.

Figure 6

Enabling Internet Calendar Sharing using a different policy

Another way to deploy Internet Calendar Sharing is creating a new Sharing Policy and then associating the new policy with a specific set of users. These are the steps that can be performed to achieve this solution:

Open Exchange Management Console
Expand Microsoft Exchange On-Premises (<ServerName>)
Expand Organization Configuration
Click on Mailbox
Click on Sharing Policies tab
Click on New Sharing Policy…
In the Introduction page. Type in the new policy name, and define the permissions and domain (Anonymous for Internet Calendar) as we’ve just seen in the previous section (Figure 7) and click Next.

Figure 7

In the Mailboxes page (Figure 8). Select mailboxes that will be set with this new policy. Let’s associate just a single user to start testing and then click Next.

Figure 8

In the New Sharing Policy page. A summary of all configuration that we have defined so far will be displayed, just click New.
In the Completion page. We will see the cmdlet used to create the new Sharing Policy and also a cmdlet for each user defined in the previous steps to receive the new Sharing Policy.

Managing Internet Calendar Sharing in Exchange Server 2010 Service Pack 1 (Part 2)

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Intorduction

In the first article we covered all steps to enable Internet Calendar Sharing on the server side, now it’s time to see how the end-users can manage their Calendar information using the new features added to the Exchange Server 2010 Service Pack 1.
Let’s say that we have just added the user to the Sharing Policy and now the user can open its Outlook Web App session and click on Calendar, and then click on Share menu, as shown in Figure 01. The user will have two new useful items: Publish This Calendar to Internet and Change Publishing Setttings (are available only after enabling the feature on the user). Let’s click on Publish This Calendar to Internet…

Figure 01
In the new window called Calendar Publishing – Calendar we can define a couple of settings to publish the Calendar, as follows:

Publishing Detail
We can define three different levels: Availability Only, Limited Details (which will show Appointment Subject, Date and time and also location), and Full details (which adds everything that we have in the Limited Details plus description of the appointment).
Note:
Bear in mind that Sharing Policy settings drive the level of Publishing Detail that the end-user can set on his own calendar. If the policy is availability only, that will be the maximum that the end-user will be able to use because Sharing Policy sets the boundaries to the end users.
Publish my calendar
User can define how many months/weeks/days before and after Today that will be published. The standard is 3 months.
Access Level
It will define if the URL created by the wizard will be easily searchable (Public) or hard to guess (Restricted).

After choosing the options we can click on Start Publishing (Figure 02).

Figure 02
The results can be seen in the Figure 03, the only difference is that now we have two URLs one link to subscribe to the calendar (a link to the calendar.ics file that can be consumed by any Calendar application) and the second one is to the Calendar virtual directory created during Service Pack 1 installation/upgrade process. The user can also click on Copy links to the Clipboard... to have both addresses in memory. We can stop anytime the Internet Calendar Sharing by just clicking on Stop Publishing.

Figure 03
If the mailbox user sends the link to an external user, the external user will be able to see the calendar using the link to view the calendar in a really nice way (Figure 04). Let’s analyze the Calendar view: first of all it is totally anonymous, it is also HTTP not HTTPS, there is no way to access user mailbox data or whatsoever, it’s just calendar information based on the configuration defined in the previous step.
Let’s also analyze what an Anonymous user that has the link can use of this new feature:

Remote user has access to the calendar using Outlook Web App experience
On the upper left side the name of the user will be displayed, besides of the URL informing the user name the remote user can double check there
On the upper right side all time range is available to the user, in the figure below the remote user won’t see any data before 11-May-2010 or after 12-November-2010
Remote user can change the time zone clicking on Time Zone section and it will change the appointments view to the desired Time Zone on the fly
Remote user can choose daily, weekly and monthly views of the calendar
Users can click on Subscribe and a file called calendar.ics will be available to download to use in your favorite software.
Remote users have the ability to print the calendar (day, week or month) just a couple of clicks away

Figure 04
If the mailbox user goes back to the Change Publish Settings… and change settings such as reduce the time range to be available or even configure the Publishing detail to Full Details all these changes will be available on the Internet view of the Shared Calendar.
If the user uses Restricted Access level a tough guess URL will be created and the user will be responsible to share the URL with his personal contacts, but if for some reason he doesn’t want to share with a specific Internet user, then the user has to stop publishing and start publishing again to recreate a new URL and then inform its contacts about the new URL.

Sharing a calendar afterwards…

The user can go back any time to the Publishing Calendar settings, clicking on Share and then Change Publishing Settings, but if the user just wants to invite a new Internet user to his calendar, he can just click on Share and then click on Send links to this calendar… as shown in figure 05.

Figure 05
The new window will be a new message that contains an invitation containing the links to view and subscribe to the user calendar (Figure 06).

Figure 06

Using Exchange Server 2010 and Windows Live Calendars…

In this section we will check both sides of the Internet Calendar sharing the subscription on Exchange side and also how an Internet Calendar service can take advantage of the published calendar on Exchange.
First, let’s start with the subscription where I’m going to use my Live Calendar (calendar.live.com) and the initial page is shown in Figure 07, and I’ve just added a couple of appointments on the calendar just to give more authenticity to our test.

Figure 07
A Live Calendar user can click on Share, and a new page will allow us to protect the calendar, just for test purposes I’m going to configure the calendar as public (I will check the option Make your calendar public) and then a link for HTML view and ICS will be available. I will be clicking on Import into another calendar application link, and the URL will be displayed in a new page, as shown in Figure 08. By the way, Live Calendar has almost the same experience of Exchange Server which makes even easier to work on both tools.

Figure 08
Let’s go back to Exchange side, opening Outlook Web App, and let’s click on Calendar item, then Share menu, and finally on Add Calendar… Let’s select Calendar from the Internet and paste the URL that we got from the previous Live Calendar page. (Figure 09)

Figure 09
The results of the operation will be a calendar with a globe icon on the left side and if it is selected the information will be displayed on the right hand side, as shown in Figure 10.

Figure 10
On the flip side, users using Windows Live Calendar can subscribe to a Calendar Published on Exchange Server 2010 just clicking on Subscribe and then they can specify the URL that was provided in the Outlook Web App, as shown in Figure 11.

Figure 11

Server tricks and tweaks

Wednesday 12 December 2012