Groove 2007

Web Abstract:

Microsoft, like many technology companies, sometimes grows by acquiring other companies. These acquisitions happen for a variety of reasons, and sometimes the rationale behind a particular purchase doesn't become clear until some time has passed. In March 2005, Microsoft bought Groove Networks, the company that created the Groove collaboration environment—but we're just now starting to see the strategy behind this acquisition with the release of the Microsoft Office 2007 system. Microsoft Office Groove 2007 fully integrates with Office 2007. Groove is a workgroup collaboration tool that lets you create a virtual office. Your team can use Groove to share files, manage meetings and projects, and track data and processes—all as if you were in one location.

Groove's History and Architecture
Groove was developed by a team led by Ray Ozzie, the architect who designed IBM Lotus Notes and who is now the chief software architect at Microsoft. You probably won't be surprised to see, therefore, that the Lotus Notes client and the Groove client share some architectural and behavioral similarities. For example, when you create a new Groove user account, the account automatically gets a digital certificate that is used to authenticate the account and to encrypt data sent to it. However, Groove is different, too, because it uses a peer-to-peer (P2P) architecture. Every client that connects to a particular Groove workspace maintains its own local copy of the workspace's information. Clients send updates directly to each other with the help of a Groove server, which you can think of as more of a coordinator than anything else. Microsoft maintains a centralized set of Groove servers, the addresses of which are hard-coded into the Groove application. However, you can deploy your own servers to take over this coordinating role by licensing Microsoft Office Groove Server 2007.

When a client reconnects after being offline, it finds its peers through queries to a Groove server, then establishes connections directly to those peers to catch up on the changes it missed while offline. The change-tracking algorithm that Groove uses is quite sophisticated; updates are tracked in small increments known as deltas. Therefore, changing one slide in a 10MB Microsoft Office PowerPoint presentation doesn't require a resynchronization of the entire file among all workspace members. The workspace where the change was created keeps a log of the deltas it "owns," purging a delta from the log only when all other workspaces confirm that they've introduced that delta into their own local spaces. The process by which an individual client determines which updates it needs from its peers is too complicated to cover here.

After its acquisition of Groove, Microsoft released an updated version of Groove Virtual Office that provided a few new features. However, the Office 2007 release of Groove is the first release to be completely integrated with the rest of Office, which smoothes the overall user experience and makes Groove capabilities more directly accessible from within Office applications and Windows Explorer.

Getting Into the Groove
Setting up a new shared workspace is simple; Groove lets you choose the type of workspace you want, from simple workspaces for sharing document files or calendar information to workspaces that automatically download and cache local copies of SharePoint sites. Figure 1 shows a sample Groove workspace. After you've created a workspace, you put content into it by dragging files and folders into the workspace view. As an alternative, when you create a workspace you can specify that it be synchronized automatically with a folder on your computer, although you can't use a Universal Naming Convention (UNC) path or a folder mapped to a remote share.

After the workspace is established, you invite other people to join it. You can send invitations via email, which lets you take advantage of the contents of your organizational Active Directory (AD) as well as your personal Microsoft Outlook contacts. You can also search for users on the Groove user directory maintained by Microsoft, which is useful for establishing workspaces that include people from different organizations. Of course, most users probably won't have existing Groove accounts, which leads to the biggest roadblock to getting started with Groove: Every workspace participant has to install Groove, then create a Groove account so that you can invite them to the workspace. This process isn't difficult, but my experience has been that many users are reluctant to install applications just for a particular project. That's part of what makes Groove's integration with Office 2007 so valuable: Many users will now already have Groove 2007 installed.

Groove Workspaces
At the most basic level, you can think of a Groove workspace as a shared folder that can contain files. When you drop a file into your local copy of a workspace, the file is copied to every other instance of the workspace without any action by the other members. This capability predates most of the file-syncing and file-sharing services now available on the Internet, and it helped fuel early adoption of Groove. Groove workspaces include many useful tools, such as IM, a calendar, an outliner, a notepad, and so on. The data items produced by these tools are automatically synchronized between copies of a workspace; if you create a new calendar entry in your copy of a workspace, it will propagate to other copies of the workspace without any action on your part. This is a surprisingly useful way to provide workgroup collaboration: As each team member adds, creates, and modifies the contents of the workspace, the changes show up in each copy. The Groove client is smart enough to detect conflicting changes and to notify you that a conflict exists; you can see the changes associated with each workspace copy and choose the one you want to keep.

Groove's synchronization infrastructure is quite robust. By default, the only function that the centralized server is responsible for is helping clients find one another; a client will choose to establish a direct connection to another client whenever possible. Groove clients talk to each other using Simple Symmetric Transmission Protocol (SSTP) over TCP port 2492. If a client attempts to reach another client and finds that the recipient isn't answering on the selected port, the sending client can use SSTP over TCP port 443 to connect to a relay server instead; the relay server collects the sender's deltas and passes them on to the receiving workspaces when they next appear on the network. This method means that security concerns for deploying Groove are minimal for most organizations; you don't need to open additional ports to allow Groove to synchronize with users outside the company firewall.

What's New and Groovy
Groove 2007 includes significant changes from previous versions. First, it integrates with the rest of Office and with Windows Explorer. For example, you can now see presence information and open IM sessions with workspace members by using the Office Communicator client, and you can send files to a Groove workspace from within Windows Explorer.

Second, the Groove 2007 client can capture the contents of SharePoint team sites or document libraries, synchronizing only the files or folders you want. This ability makes your workflow simple and straightforward: You can work directly with the items you need while you're connected to your network, then synchronize the contents to a Groove workspace to get full offline access to those same items while you're traveling. You can make changes to the items, then check them back into their original SharePoint locations automatically the next time you connect to the network. Because SharePoint also offers team calendars, contacts, and lists, you can intermix Outlook's and Groove's offline functionality to coordinate your work with others. However, this synchronization is limited in scope: Only the workspace that originally establishes the sync relationship with a SharePoint site can put changed data back into that same SharePoint site. Suppose that Alice synchronizes her team SharePoint site with a Groove workspace. If Bob and Charlie are workspace members, they can make changes to the workspace data, but those changes won't propagate back to SharePoint until Alice initiates synchronization. In fact, if Alice has a copy of her workspace on a computer at home, that workspace can't push changes back to SharePoint either; only Alice's original workspace can do so.