Microsoft Office 365: Stepping Stone to the Cloud

While moving to the cloud may be inevitable, Microsoft Office 365 and Exchange Online can facilitate the period of coexistence that will be part of most migration paths.

Alan Maddison

It seems that everyone is thinking about the cloud. Many organizations have already started moving to the cloud and have found tremendous benefits and positive impact on IT operations and the business as a whole. Some of these benefits include improved agility and responsiveness to the business units. This helps improve IT value and increase innovation, and helps position the business for long-term success.

Gartner Inc. has predicted revenue from the cloud will grow more than 300 percent to $150 billion within three years. These projections are based on the fact that the benefits of moving IT operations to the cloud can be substantial.

From a more practical perspective, moving to the cloud also changes how IT impacts the balance-sheet. Cloud computing moves capital expenditures to ongoing operating expenses. Because of the inherent flexibility of cloud computing, these operating expenses are generally lower. Organizations are able to more efficiently optimize their IT environments from a sizing perspective. For those organizations moving to the cloud, the days of spending hard-to-come-by budget dollars on servers that end up being significantly underutilized become a distant memory.

Despite the significant tangible benefits, such a fundamental shift in IT operations is not without its challenges. Network connectivity, data security and the ability to meet regulatory compliance mandates are some of the common challenges cited by companies as they consider moving to the cloud.

As with any technology that creates such a fundamental shift in IT operations, many companies are approaching the move to the cloud with caution. Those companies that do make the leap are looking to maximize the value of this change. For many, the most effective approach is to first transition a simple solution like messaging.

Coexist with the Cloud

Many organizations seem to be taking a hybrid approach to moving their messaging to the cloud. There are valid reasons for this type of user segmentation. This approach can offer benefits that aren’t achievable in other ways. When you have an on-premises Exchange Server infrastructure coexisting with Exchange Online—one of the core offerings of Microsoft Office 365—there’s a rich feature set at your disposal.

Any organization that decides to move their messaging environment to the cloud will experience a period of coexistence with the existing and cloud infrastructures. For organizations moving their entire messaging infrastructure to the cloud all at once, the period of coexistence will last only as long as the migration. In this scenario, there should be limited impact on feature availability during the transitional phase.

For long-term coexistence, the available feature set becomes much more important. It represents a core element of the functionality available between cloud-based users and on-premises users. As you consider moving some segment of your users to the cloud, it’s important to remember that Microsoft defines both simple and rich feature sets.

As the name implies, the simple feature set offers a limited set of features—including mail routing with a shared namespace and a unified Global Address List (GAL). For long-term coexistence, there’s only one practical choice. The rich feature set will require that you have an Exchange 2010 SP1 infrastructure on-premises. This can be a single server hosting the Hub Transport, Client Access and Mailbox roles (required to support legacy Public Folder access).

You don’t have to abandon your Exchange 2003 or Exchange 2007 servers, but they need to coexist with an Exchange 2010 server. If you’re working with an existing Exchange 2003 or Exchange 2007 environment, you need not size the new Exchange 2010 server as if it were going to replace your existing servers.

This makes for a cost-effective approach to ensuring that users have a seamless experience. One of the many other benefits to this approach is that when it comes time to move user mailboxes to the cloud, you can move them directly from Exchange 2003 or Exchange 2007 servers using the Remote Move feature in the Exchange 2010 Management Console.

This is also true for an online move, as the user won’t really be aware that his mailbox has been moved. Outlook uses Autodiscover to handle the change in configuration. Also, because this move is a true move and not just copying to a new mailbox, Outlook will not force an offline storage (OST) re-synchronization. This alone can significantly reduce network traffic and help ensure that your users enjoy a transparent experience as they’re transitioned to the cloud.

From your perspective, another important consideration is the bidirectional flexibility of mailbox moves. In a process known as off-boarding, you can choose to move mailboxes from the cloud to the on-premises infrastructure.

A New Mode of Messaging

One of the most compelling aspects of a hybrid solution is that there’s nearly complete parity when looking at the feature set available to a cloud user and an on-premises user. Much of the rich feature set will work with any supported Outlook client. The Microsoft Federation Gateway, which is required as part of the deployment topology and the Exchange 2010 Client Access server role, makes this possible.

Microsoft has put a lot of thought into ensuring that the experience of an organization’s user is seamless regardless of whether they’re in the cloud or on-premises. This includes supporting mobile devices with Exchange ActiveSync and providing self-service remote wipe in the event that a user loses her cell phone. There are a number of other fundamental features that help create the look and feel of a seamless experience. These include the ability to have a shared namespace, a single GAL and a unified Free/Busy, shared calendars and shared mailboxes.

What this means in practical terms is that regardless of the location of a user’s mailbox, the user will be able to interact with her coworkers as if they were all on the same Exchange infrastructure. Typical day-to-day tasks such as setting up meetings, checking users’ availability, searching for users and looking at calendars remain unchanged. If your users are using Outlook 2010, the time-saving tools to which they’ve become accustomed—such as mail tips, conversation view and meeting room finder—will continue to work seamlessly.

Make Room for Mail

Exchange Online will support mailboxes up to 25GB. Because many organizations haven’t even come close to offering mailboxes that large, many users will actually look forward to moving to the cloud. For those users that access their mail from the Web using Outlook Web App (OWA), the rich feature set supports cross-premises OWA redirection. This means all your users can access OWA through a single URL with the on-premises Client Access server handling the redirection.

The amount of thought that Microsoft has given to ensuring a transparent user experience will have a tremendous positive impact from a support perspective. Your users won’t have to learn new ways of doing things. You can expect the number of help-desk tickets associated with mailbox moves—and the migration in general—will remain relatively low.

Archiving with Ease

When looking at the operational aspects of day-to-day administration, it’s important to understand the underpinnings that provide this best-in-class user experience. Perhaps the most fundamental aspect of the hybrid approach is the centralized mail routing topology. This ensures that all mail flows into and from the on-premises infrastructure. As a result, the message header—including the authorization header—is retained on all messages. This means any message from the cloud is treated as authenticated. Message tracking started from either the cloud or on-premises will be a complete process from start to finish. Exchange Online also supports on-premises Rights Management Server, which means support for Information Rights Management in Outlook and OWA.

You can access key legal-discovery features such as mailbox archiving, retention policies and legal hold through Hosted Archiving. Even if you don’t need Hosted Archiving, simply searching through mailboxes is another transparent feature. You can select a mailbox from either the cloud or on-premises, and run a search that returns results regardless of the mailbox location. Finally, a roles-based access control, or RBAC, model gives you granular control of scope and permissions to ensure that you manage your infrastructure in an efficient and secure manner.

Make the Move

Moving to the cloud has many intricacies, but the myriad benefits make doing so worthwhile. You’ll realize increased IT responsiveness, flexibility and efficiency—not to mention the ability to optimize a large portion of your IT budget.

Microsoft Office 365 offers a compelling choice for any organization looking to move to the cloud. While Office 365 is still officially in beta, Exchange Online has a solid track record outside the current Office 365 offering. The power and flexibility it offers customers in how they manage their move to the cloud has proven value, and is a key differentiator for Exchange Online in any co-existence scenario.

Alan Maddison

Alan Maddison is a 16-year veteran of the IT industry, during which time he has focused primarily on Microsoft technologies. For the last five years he has worked as a consultant focusing on delivering professional services. He can be reached at

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