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Deploying Active Directory Rights Management Services at Microsoft

Technical White Paper

Published: December 2011

The following content may no longer reflect Microsoft’s current position or infrastructure. This content should be viewed as reference documentation only, to inform IT business decisions within your own company or organization.

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Situation

Solution

Benefits

Products & Technologies

Sensitive business information created in Microsoft Office as email or business documents was at risk of exposure to unauthorized users.

Microsoft IT implemented Active Directory Rights Management Services (AD RMS) so that publishers could use Microsoft Office applications to restrict access to confidential data.

  • Publishers can apply detailed user rights to email messages and documents.
  • Sensitive information can be distributed as required with less concern that unauthorized users will access it.
  • AD RMS fulfills the requirements of multiple information protection technologies, simplifying the user experience and IT support tasks.
  • The AD RMS infrastructure is extensible to other, internally developed line-of-business applications.
  • Windows Server 2008 R2 with SP1
  • Active Directory Domain Services and Active Directory Rights Management Services
  • Microsoft SQL Server 2005 and SQL Server 2008
  • Microsoft Office 2010
  • Microsoft SharePoint Server 2010
  • Microsoft Exchange Server 2010
  • Windows Mobile 6.x

Contents

Ee156482.arrow_px_down(en-us,TechNet.10).gif Executive Summary

Ee156482.arrow_px_down(en-us,TechNet.10).gif Introduction

Ee156482.arrow_px_down(en-us,TechNet.10).gif Active Directory Rights Management Services

Ee156482.arrow_px_down(en-us,TechNet.10).gif AD RMS Technology

Ee156482.arrow_px_down(en-us,TechNet.10).gif Business Benefits of Deploying AD RMS

Ee156482.arrow_px_down(en-us,TechNet.10).gif Deployment of AD RMS at Microsoft

Ee156482.arrow_px_down(en-us,TechNet.10).gif Lessons Learned and Best Practices

Ee156482.arrow_px_down(en-us,TechNet.10).gif Conclusion

Ee156482.arrow_px_down(en-us,TechNet.10).gif For More Information

Executive Summary

With the continuing advancements and ubiquity of electronic communications in business, in addition to the growing reliance on technology for conducting day-to-day operations, companies have become vulnerable to the mismanagement and theft of intellectual property and sensitive business information. Microsoft employees rely very heavily on email through the Microsoft Outlook 2010 messaging and collaboration client for both internal and external business communications. Microsoft employees also rely on Microsoft Office 2010 applications—such as Microsoft Word 2010, Microsoft Excel 2010 spreadsheet software, the Microsoft PowerPoint 2010 presentation graphics program, and the Microsoft InfoPath 2010 information gathering program—to document and work with corporate ideas and other business-sensitive information. To remain a flexible and agile business, Microsoft needed a solution that could help protect the data of its business email messages and documents without interfering with its users' ability to be productive.

The Microsoft information Technology (Microsoft IT) organization implemented Active Directory Rights Management Services (AD RMS), which is the protection server role available in the Windows Server 2008 R2 operating system. It is the successor to Rights Management Services (RMS) available for Windows Server 2003. AD RMS combined with Office 2010 enables Microsoft staff to add usage restrictions to their email messages and documents. The rights can specify which consumers can open the document, what they can do with it, and how long they can open it. The rights are applied directly to the object, whether an email message or a document file, so the protections stay with the object regardless of whether it is sent in email or stored as a file. Each protected message or document is encrypted and requires a use license from the AD RMS server to decrypt the content and to apply the usage restrictions that are assigned to the consumers of that content.

Although the introduction of such a far-reaching solution is always complex, Microsoft IT found that the design and implementation process was relatively straightforward. After Microsoft IT identified the appropriate information-protection policies, mapping them to actual rights to be used and deploying the necessary technology did not involve any major environmental changes. Microsoft IT deployed both the server and client components without major impact to the users or to operational areas at Microsoft IT.

Since the worldwide implementation of AD RMS at Microsoft, approximately 170,000 unique users apply the technology to 7,000 documents and email messages every day. These numbers continually grow as an increasing number of users adopt AD RMS technologies as their preferred means of helping to protect their confidential documents and email messages.

This paper discusses the need that Microsoft IT had for protecting confidential business data, the reasons for deploying AD RMS over other possible solutions, updates since the initial deployment, and how AD RMS works. This paper also offers detailed lessons learned and best practices derived from the AD RMS server and client deployment and the usage experience of Microsoft IT. It assumes that readers are technical decision makers and are already familiar with the fundamentals of both public key cryptography and symmetric key security systems, the benefits that such systems offer, and the components that are required to implement the systems.

This paper uses the term publisher to denote someone who creates rights-protected content, such as an email message or a document created in Microsoft Office Enterprise 2007. The term consumer denotes someone who must retrieve a use license to open rights-protected content.

This paper is based on Microsoft IT's experience and recommendations as an early adopter. It is not intended to serve as a procedural guide. Each enterprise environment has unique circumstances. Therefore, each organization should adapt the plans and lessons learned described in this paper to meet its specific needs.

Note: For security reasons, the sample names of forests, domains, internal resources, and organizations used in this paper do not represent real resource names used within Microsoft and are for illustration purposes only.

Introduction

The privacy and security of confidential data and intellectual property are vital to a business. If a corporate email system or a business productivity application does not allow an organization to control who can see email messages and documents after they are sent to consumers, that system or application is limiting the organization's ability to conduct private business with agility and efficiency.

Many businesses today may be unnecessarily restricting the use of email systems or intranet websites for the dissemination of their confidential data because they lack knowledge of the technologies that are available to help safeguard that data. Conversely, other businesses simply may not comprehend the magnitude of the issue of electronic data privacy and security. They unintentionally and unnecessarily expose their confidential data to people or organizations that were never intended to have access.

Microsoft, like any other business that creates valuable intellectual property in a highly competitive marketplace, needed the ability to better safeguard the privacy of its confidential data. Microsoft IT recognized that it needed technology to control how sensitive business email messages and business productivity documents could be shared and used, without risking losses in productivity.

More specifically, Microsoft IT needed to implement technology that offered the publisher of confidential email messages and business productivity documents the ability to manage who could consume their content, and to limit usage of their content on a document-by-document basis. Without such technology, intellectual property, trade secrets, or incident management data belonging to Microsoft or its business partners might have been inadvertently or even maliciously exposed to the public, the media, or business competitors.

Active Directory Rights Management Services

Microsoft IT considered various technology tools that could help protect the confidentiality of sensitive data in business documents. However, in many cases, a viable solution for protecting one type of document placed unreasonable or technologically unfeasible demands on another type of document. Most of the solutions considered were simply incomplete or too easily bypassed by individuals with malicious intent.

The tool that Microsoft IT selected was AD RMS, a Microsoft .NET–connected web service provided by Windows Server 2008. R2.

Note: AD RMS is a role of Windows Server 2008 R2. However, AD RMS requires the purchase of client access licenses for each user who is publishing and/or viewing rights-protected content.

AD RMS works with AD RMS–enabled applications, such as Office 2010, to enable publishers to control who can view their confidential content by attaching a usage rights policy directly to an object (such as an email message or a document file). The rights can restrict how the content is used and who is allowed to use it. An organization can set different rights for various individuals and/or groups, based on user accounts in Active Directory Domain Services (AD DS, in Windows Server 2008 R2), users in trusted AD RMS environments, users in other directories integrated with Active Directory Federation Services (AD FS), and users of the Windows Live ID–based AD RMS service. User rights for consumers can also be set to expire after a finite period.

Note: Currently, Microsoft IT allows internal users to trust content published by its internal AD RMS servers and a limited number of third parties.

Usage rights policies are associated directly with the protected content, not the container in which it is stored. Unlike access control list (ACL) permissions from a file system such as the NTFS file system, email messages and documents that are protected through AD RMS technologies remain protected whether they are:

  • Forwarded to an email account outside the corporate firewall.

  • Sent as an email attachment.

  • Stored on a Microsoft SharePoint website, a shared folder on a file server, a CD-ROM, a universal serial bus (USB) drive, or a floppy disk.

Microsoft Office email messages and documents that are rights-protected employ 128-bit encryption to help prevent unauthorized viewing and usage of content.

AD RMS serves as the platform for this technology. However, Microsoft also needed a client application that applied the technology of AD RMS. Microsoft IT found the solution with its enterprise-wide deployment of Office 2010. Office 2010 has a feature called Information Rights Management (IRM), which enables policy rights definitions to be applied to both email messages and documents that are created in the Word 2010, Excel 2010, Outlook 2010, PowerPoint 2010, and InfoPath 2010 applications.

At this time, there are no AD RMSenabled applications to specifically help protect content within databases or within development environments for software source code. However, those environments are typically locked down by other means to help protect their valuable data from unauthorized access. AD RMS helps protect business documents, where confidential ideas, proposals, incident reports, and financial data are stored and used on a daily basis. AD RMS complements existing data safeguards within the enterprise organization, which enhances the organization's overall ability to protect its internal, private information.

Comparison with Other Technologies

AD RMS is not the only technology that can help safeguard the contents of email messages and business productivity documents. Other technologies include Secure/Multipurpose Internet Mail Extensions (S/MIME), ACLs, Encrypting File System (EFS), and Windows BitLocker Drive Encryption. Each of these technologies serves a valuable purpose, and all are used within Microsoft. However, each of these technologies helps protect data only in a specific set of circumstances. This section briefly describes the technologies and compares them with AD RMS to explain why Microsoft IT chose to deploy AD RMS.

S/MIME

S/MIME is a security-oriented superset of Multipurpose Internet Mail Extensions (MIME), an industry-standard protocol widely used on the Internet for email. S/MIME adds public key encryption and support for digital signatures to MIME. Support for S/MIME technology has been available for several versions of Microsoft messaging products. However, S/MIME does not help protect confidential documents outside the realm of email; nor does it control usage rights, such as the ability to restrict copying or printing protected information. Furthermore, after a recipient opens S/MIME-protected content, that recipient can forward the content to other recipients with the original protection removed.

ACLs

Security in Windows Server controls the use of objects through the interrelated mechanisms of authentication and authorization. After a user is authenticated, Windows Server uses authorization and access control technologies to determine whether an authenticated user has the correct authorization to access an object that is protected through access control lists.

ACLs for file and folder permissions require the use of NTFS. Any permission restrictions that are assigned to a document through ACLs are eliminated when the file is moved from the container where the permissions were set to another container that does not use NTFS. For example, an ACL that restricts all access to a document to a particular set of users will no longer be applied after that file is sent via email or is copied by an authorized user to a disk medium that is not using NTFS (such as a floppy disk, a CD-ROM, or a hard disk formatted through any variety of the FAT file system). The document is then available to all users who have access to that medium.

Also, ACLs allow any user who can read a document to copy, edit, or print the contents, so users who are allowed to access the document must be trusted not to redistribute the content inappropriately.

EFS

EFS helps protect sensitive data in all types of files that are stored on disk via NTFS. It uses symmetric key encryption in conjunction with public key technology to provide confidentiality for files. In EFS, unlike most other external encryption services, file encryption does not require the file owner to decrypt and re-encrypt the file on each use. Decryption and encryption occur automatically as the file is read from and written to the disk. Files retain EFS encryption when they are moved and renamed, if they stay on NTFS volumes. Copying or moving an encrypted file or folder to a disk medium that is formatted through any file system other than NTFS removes the encryption and returns the file to its normal format.

Additionally, only the person who applied EFS encryption to a file or users who are specifically assigned the right to decrypt files can decrypt the file and work with it. Other users—even a file owner—cannot open an EFS-encrypted file unless a decryption key has been generated and encrypted through a public key.

BitLocker Drive Encryption

BitLocker, a technology in the Windows Vista Enterprise and Windows Vista Ultimate operating systems and in all editions of Windows Server 2008, allows for the encryption of complete disk volumes, including all the data that they contain. This provides integral protection against offline unauthorized access of operating system files, data files, and metadata.

Because data decryption occurs automatically when the system is running, BitLocker does not protect data against authorized users of the system. However, strong drive encryption effectively blocks offline attacks (such as those typically performed on stolen laptops). BitLocker can store the drive encryption keys in a Trusted Platform Module (TPM), a hardware device that allows for the security-enhanced storage of security keys, among other functions. The TPM also assists in the validation of the startup sequence to detect unauthorized modification before the user is allowed to log on.

The encryption keys can also be stored in a USB key that is then necessary for the computer to start. Alternatively, the encryption key can be stored in the system and protected through a personal identification number (PIN) that the user must manually enter every time the computer starts.

BitLocker provides strong protection against unauthorized computer access. However, it does not differentiate between users, so it is not a tool to provide protection between different authorized users of a system. Also, because BitLocker applies to the storage medium directly and not the data files, data is only protected as it is stored in the original disk. Copying of the data by an authorized user to another system or to another unprotected storage medium removes all BitLocker protection from the data.

Feature-Based Comparison

Table 1 compares IRM and AD RMS in Microsoft Office with S/MIME digital signing, S/MIME encryption, ACLs, EFS, and BitLocker.

Table 1. Comparison of Technologies Used to Help Safeguard Confidential Data

Feature

IRM and AD RMS

S/MIME signing

S/MIME encryption

ACLs

EFS

BitLocker

Attests to the identity of the publisher

Yes1

Yes

No

No

No

No

Sets a detailed usage policy on information

Yes

No

No

Yes

No

No

Prevents unauthorized viewing

Yes

No

Yes

Yes

Yes

Yes

Encrypts protected content

Yes

No

Yes

No

Yes

Yes

Offers content expiration

Yes

No

No

No

No

No

Offers use license expiration

Yes

No

No

No

No

No

Controls reading, forwarding, saving, modifying, or printing of content by the consumer

Yes

No

No

No2

No

No

Extends protection beyond the initial publication location

Yes4

Yes

Yes

No

Yes3

No

Keeps information protected even when outside a user's direct control

Yes4

No

No

No

No

No

Offers the ability to collaborate with others on protected information

Yes

No

No

Yes

Yes

No

Helps protect information through a smart card

No5

Yes

Yes

No5

Yes

No

Helps protect information from other users on a shared computer

Yes4

Yes

Yes

No

Yes

No

Helps protect information on a lost or stolen laptop

Yes4

Yes

Yes

No

Yes

Yes

Provides a physically nonsecure branch office server

Yes

Yes

Yes

No

Yes

Yes

Applies to all document formats

No

No

No

Yes

Yes

Yes

1 AD RMS relies on user authentication at the operating system level to validate the user's identity. Although AD RMS utilizes strong document-signing operations, these capabilities should not be used for non-repudiation, as AD RMS persists a Publishing License unmodified after modifications or replies to a document by other people, including the superuser and any authorized users, limiting the usefulness of the signature as proof of originality and non-repudiation.

2 ACLs can be set to modify, write, or read-only but apply to the original container of the document.

3 EFS encryption is maintained with a copied or moved file only if the destination folder is also on an NTFS-formatted volume and (for copying ) the destination folder is marked for encryption.

4 IRM technologies rely on the integrity of the client computer's lockbox. Thus, a skilled attacker who has direct control of the files where a document is stored might be able to perform unauthorized operations with the document. Also, if an attacker obtains credentials for a user who has rights to perform operations on a document, either through technical means or social engineering, the attacker can perform any operation on the document that the legitimate user has rights to perform.

5 These protection systems rely on user authentication at the operating system level to provide access to the protected content. Although these technologies do not support storing the encryption key directly on a smart card, they support storing it under a protected store that can be accessed only after the user is authenticated. This process can require a smart card if the corresponding policies are enabled.

After analyzing the various technologies for safeguarding confidential data and comparing them with IRM and AD RMS, Microsoft IT determined that IRM and AD RMS met most of its requirements. Although Microsoft IT determined that no single solution would cover all potential risks to unauthorized data disclosure, AD RMS offered an excellent complement to other technologies that help protect systems and data, providing key protection to documents regardless of their location and applying usage policies that that limit the unauthorized distribution of documents. The ease of use for both generation and consumption of protected documents would also help keep support costs low—a factor that an organization always must consider when introducing new technology that affects end users.

AD RMS Technology

When someone attempts to open a rights-protected document or email message, AD RMS identifies the consumer through the Simple Mail Transfer Protocol (SMTP) email address assigned to the consumer's Active Directory logon account. AD RMS then compares this identification with the list of rights associated with the protected content. If the specified consumer has been granted user rights, either individually or through inclusion in a distribution group, the AD RMS server issues a use license to the consumer.

Note: If the SMTP address specified in the list of rights is for a distribution group, AD RMS must perform a lookup against Active Directory data to determine whether the end-user account object is associated with the distribution group.

Licenses

To open documents that AD RMS–enabled applications help protect, a consumer needs a digital license from the AD RMS server. There are two types of licenses: publishing and use.

Publishing License

A publishing license is created when a document (including an email message) is originally protected. Every protected document gets its own publishing license. AD RMS provides for the creation of publishing licenses in two ways: online and offline. Online publishing requires connectivity with the AD RMS server, whereas offline publishing does not.

IRM in Microsoft Office always publishes its content offline. To do so, the AD RMS client computer generates a publishing license without contacting the AD RMS server. However, for the publishing license to be generated, the offline client must have already been activated and received its publishing certificate. The publishing certificate is generated by the AD RMS server and downloaded to the client computer when its first piece of rights-protected content is published, requiring online access to the AD RMS server.

End-User License

An end-user license (also called use license, UL, or EUL) is required to open the protected content. An AD RMS–enabled application uses the EUL to decrypt the content, and then enforces the specific usage restrictions assigned to the consumer. Each protected piece of content requires its own use license.

The AD RMS server generates use licenses in response to a valid license request, which typically occurs when a consumer who has rights to a protected email message or document opens that item for the first time. Use licenses can be cached and reused to open a protected document, depending on the rights policy. In cases with Microsoft Office documents, if the consumer has write access to the file, the use license is appended to the protected document file. The user can then open the protected content again on any computer that has been activated with that user's account without requiring network access to the AD RMS server until the use license expires.

With Outlook email messages, the consumer computer stores the use license locally after the computer obtains it from the AD RMS server. Because Microsoft IT uses Outlook with cached mode enabled, it configured Outlook to automatically obtain use licenses for rights-protected email messages during the synchronization process with a server running Microsoft Exchange. Microsoft IT specifically enables this by setting a registry key during installation. If Microsoft IT had left the default setting in place, at the first time that the consumer attempted to open a rights-protected email message or document, a dialog box would have appeared, asking whether the consumer wanted to permanently enable this behavior. If enabled, this option would have set the same registry key that Microsoft IT preset during installation.

Some policies can be set to expire use licenses after each time a consumer accesses protected content. In these cases, the consumer must have online access to the AD RMS server to receive another use license before that content can be reopened.

Types of Rights Available

By using AD RMS–enabled applications, such as Word 2010, Excel 2010, and PowerPoint 2010 from Microsoft Office Enterprise 2010, a document publisher can apply rights to a document file through one of three methods:

  • Default rights that apply to all consumers (such as Read or Change)

  • Customized combinations of rights that are assigned to each specified individual or group of consumers

  • Templates that the AD RMS administrator creates to apply a predefined set of rights to a predefined set of individuals or groups of consumers

Alternatively, email senders can use Outlook to apply rights to the message and any unprotected Word, Excel, or PowerPoint document attachments that might be included. By default, the only rights setting that Outlook 2010 offers is a do-not-forward right for email messages and any attached document files from applications that support AD RMS. However, an administrator can create customized rights policy templates for Outlook to expand the number of offered rights.

Each of the rights available in IRM-enabled editions of Office 2010 offers or limits certain activities that a consumer can perform with the protected content. The rights that IRM makes available can grant or deny consumers permission to read, save, copy, modify, print, and forward protected objects. User rights can also be set to expire on a preset date. Table 2 discusses the details of what each of these rights does to help protect content.

Table 2. IRM Rights and Their Definitions

Right

Description

Full control

This right gives the consumer the same abilities that the publisher has. This right acts as if no rights restrictions have been applied. It is typically enabled only for an individual who is a member of a larger group of consumers for whom rights that are more restrictive have been applied. It can also be used to transfer ownership of a document.

Change

This right enables the consumer to read, edit, and save changes to a protected document (but not print).

Read

This right enables the consumer to read a protected document but not print, edit, save, or copy (and with Microsoft Office Outlook 2003 and Office Outlook 2007, also not forward).

Document expiration

This right expires the consumer's ability to open a protected document at a date that the publisher set.*

Print content

This right enables the consumer to print protected content. If this right is not assigned, the user cannot print the document, even if he or she can open it and view it.

Allow users with read access to copy content

This right enables the consumer to read and copy the content of a protected document to the Clipboard but not print, edit, or save the original document. If this right is assigned, the user might be able to copy the content to another document and then print or save it from there, so it should be assigned with care.

Access content programmatically

This right enables another application to access protected content programmatically.

Users can request additional permissions

This right enables the consumer to contact the publisher at a specified email address to request an upgrade in the assigned rights.

Allow users with earlier versions of Office to read with browsers supporting Information Rights Management

This right enables protected content to be read in Windows Internet Explorer through the Rights Management Add-on (RMA).

Require a connection to verify a user's permission

This right sets the use license to expire immediately after the protected content has been accessed. As a result, the consumer must have online access to the AD RMS server to get another use license every time the document is opened.

* Document expiration does not destroy the document. Only the right to open the document expires.

Note: IRM rights in Microsoft Office 2003 and Microsoft Office 2007 can be applied only to the entire document and not to parts of the document.

Table 3 lists the policy restrictions available in the AD RMS–enabled applications within Office Professional Edition 2003 and IRM-enabled editions of Office 2007.

Table 3. Applicable Policy Restrictions

Outlook

Word, Excel, PowerPoint, and InfoPath

Read (cannot forward, print, save, or copy)

Full control

Change content but no printing

Read (cannot print, save, or copy)

Read with copy content permission*

Print content*

Document expiration*

Enable content access programmatically*

Require new license with every access*

Provide email address for users to request upgraded rights*

Enable content access by means of RMA*

* In InfoPath, these capabilities are available only for forms, not for form templates.

In Microsoft Office 2007, rights are applied to objects hierarchically. For example, consider a Microsoft Office Word 2007 document that is attached to an Office Outlook 2007 email message. If rights are not applied to the document before it is attached but are subsequently applied to the email message, the attached document inherits the rights applied to the email message. If rights are applied to the document before it is attached, email rights do not affect the document's rights.

In Office Outlook 2003 and Office Outlook 2007, a message can be expired at a certain date through the Expiration setting under Options. If the Do Not Forward (the read-only setting) option is selected and message expiration is set, IRM enforces the expiration setting.

Note: Expired content does not delete itself—it only locks out the consumer. The publisher and members of the Super User distribution group can still open the content.

Customized AD RMS Templates Available from Microsoft IT

The IRM-enabled applications in the corresponding editions of Microsoft Office support the use of preconfigured, default, rights-setting policy templates to help enterprises define the most commonly needed standardized sets of rights for safeguarding documents.

For example, with Outlook email, the only default assignable IRM setting is Do Not Forward. Through an AD RMS template, customizable rights beyond the default can be applied. All of the AD RMS–enabled applications in Microsoft Office support the same policy templates.

Microsoft IT offers users at Microsoft six AD RMS templates to help protect Microsoft Office email messages and documents. All of these templates define the intended audience, based on the use of specific distribution groups and the specific rights provided to that audience. The templates are as follows:

  • Microsoft All – All Rights

  • Microsoft All - Read Only

  • Microsoft All – All Rights Except Copy and Print

  • Microsoft FTE – All Rights Except Copy and Print

  • Microsoft FTE - Read Only

  • Do Not Reply All

The first three templates use the Microsoft All Staff distribution group. This group includes all Microsoft full-time employees (FTEs), contractors, and vendor staff. Any person not included in this distribution group, such as people outside the company, cannot open content that this template helps protect. The second template is a modification of the first with restrictive read-only rights.

The fourth and fifth templates use the Microsoft All FTE distribution group. Any person not included in this distribution group—such as contractor and vendor staff, along with anyone outside the company—cannot open any content that this template helps protect. The fifth template applies the restrictive read-only rights to the Microsoft All FTE distribution group.

Finally, when the Do Not Reply All template is applied to a message, its recipients cannot use the Reply All function. This restriction prevents large volumes of response traffic to messages that are sent to many recipients.

The master version of a rights policy template resides in the AD RMS database and is always used when a use license is created so that the most recent policy set by the AD RMS administrator is enforced. Each AD RMS client must download the templates that it will use. These local versions of the templates do not need to be updated every time the AD RMS administrator updates the template, because the AD RMS server uses its own copy when it evaluates the rights that the template specifies. However, templates still must be available locally for a user to select them when he or she performs offline publishing, as in the case of Microsoft Office applications.

If the feature that requires a new use license with every access is used with a template, the organization can dynamically change rights policies after the document is published or sent in email. This way, the organization retains the option to further restrict or loosen control on one or more users at any time.

Exchange Prelicensing

Alternatively, when a content publisher is using Outlook 2010 or Microsoft Outlook Mobile on Windows Phone with AD RMS, an optional Microsoft Exchange Server 2010 component called the Exchange Prelicensing agent can perform the user validation and authorization at the Exchange Hub Transport server, and issue the use license before the message is delivered to the user. This means that when the user receives the message, the use license is also received and stored together with the content, preventing the need for the user to connect to the AD RMS server when the message is open.

The Exchange Prelicensing agent is part of Microsoft Exchange Server 2007 with Service Pack (SP) 1 or later and is installed automatically on all Hub Transport servers installed with this version. For Exchange Prelicensing agent to work reliably, it must be installed on all Hub Transport servers in the infrastructure. All those servers must be running Exchange Server 2007 with SP1 or later. Additionally, the AD RMS client on the 64-bit editions of Windows Server 2008 must be installed on the computers that perform the Hub Transport server role.

Secure Sockets Layer Connections Used for All AD RMS Communications

Microsoft IT configured AD RMS such that all communications between clients and the AD RMS servers are conducted through Secure Sockets Layer (SSL) tunnels, regardless of whether the connection passes through the corporate firewall. This extra precaution helps ensure the security of the transmitted data. All SSL certificates use 2,048-bit encryption.

AD RMS Licensing Outside the Firewall

The AD RMS licensing process functions essentially the same way whether the content consumer is within the publisher's network boundary or outside it. For content consumers at Microsoft who are attempting to open internally licensed rights-protected content outside the corporate network boundary, Microsoft IT placed the AD RMS servers in a perimeter network (also known as a DMZ, demilitarized zone, and screened subnet) between its firewalls. This configuration enables users who have Internet connections to receive the use licenses that they need to open protected content.

For valid consumers of rights-protected content to be able to open that content when they are outside the Microsoft corporate firewall, a pair of URLs (one internal, one external) for the server that created the document's publishing license (or in the case of the use of a client licensor certificate [CLC], the server that issued the CLC) was embedded within the publishing license of every protected document. If the content is not prelicensed through the Exchange Prelicensing agent, which is the case for all Microsoft Office messages, the Microsoft Office application first attempts to connect to the AD RMS server via the intranet URL to get the use license. If the application cannot resolve the internal URL, it attempts to use the external URL.

As long as the client computer is connected to the Internet, it can access the AD RMS server. However, because the user is not authenticated on the Microsoft corporate network, the consumer will first be prompted for user-name and password credentials. After the server validates the credentials, it can issue the use license (and, if necessary, a temporary rights account certificate [RAC]), enabling the client to open the protected content. If the content is prelicensed, the use license is already in the client, so no connection or authentication request occurs.

Note: For any computer on which the consumer has not logged on by using domain credentials, such as an employee's home computer, trying to access content that has not been prelicensed, the enterprise AD RMS server issues a temporary RAC for opening rights-protected email and documents. It does this after prompting for the consumer's logon credentials. The temporary RAC is valid for only 30 minutes. The employee's home computer must download a new temporary RAC to open rights-protected content if any existing temporary RAC has expired. An alternative is to use Microsoft Office Outlook Web Access, which can create or consume protected content with any browser.

Caveats for Semi-Trusted Computers

Microsoft IT classifies employee-owned home computers running any operating system that Microsoft IT does not manage, but are used to access corporate email, as unmanaged computers. Microsoft IT classifies employee-owned mobile devices that are used to read corporate email as semi-trusted computers because Microsoft Exchange ActiveSync can push policies to the device to enforce a PIN and device encryption for access.

The ability of the content consumer to open rights-protected email messages and documents depends on the ability of the consumer's computer to acquire and use digital licenses. Because of the wide variety of hardware computing platforms and possible operating system and software configurations, and because Microsoft IT does not manage these computers, properly configuring semi-trusted computers to open rights-protected email messages and documents can be challenging for the end user.

Limits on Creating Rights-Protected Content

There are two options for employees to create and consume IRM-protected content. The first option is to use Outlook Web Access from the browser. Outlook Web Access provides full IRM integration in which Exchange Server performs the encryption and decryption process. Full Outlook Web Access/IRM access is available for desktop and mobile browsers that support the full Outlook Web Access experience.

The second option is to use Office 2010 (for Windows 7 users) or Microsoft Office for Mac 2011 (for Mac OS X users).

IRM with Windows Phone 7.5

Email is a basic tool in most organizations today. Information workers use email to exchange all kinds of sensitive information, including financial data, legal contracts, intellectual property, and competitive analyses. Although they may not have been designed as such, email systems have become repositories of sensitive data. Exchange Server 2010 with SP1 and Windows Phone 7.5 mitigate the risk of data leakage by using IRM to provide persistent online and offline protection of email messages and attachments.

IRM applies AD RMS to email so that messages can circulate within a protected environment for authorized users but not be forwarded outside the organization. AD RMS can also be applied to Microsoft Office documents, which can be sent to Windows Phone 7.5 users as attachments. Windows Phone 7.5 is the only smartphone currently available that includes built-in functionality to handle rights-managed email and Microsoft Office documents. The ability to access email from almost anywhere is increasingly common, and information workers typically access and work with email messages from office computers and laptops as well as from smartphones. Although the availability of email enhances productivity in countless ways, sensitive email data is subject to increased risk from data leakage.

Business Benefits of Deploying AD RMS

Microsoft realized several benefits after Microsoft IT deployed AD RMS combined with the IRM feature in Microsoft Office. AD RMS fills a technology gap that no other product serves, both in the email space and with other business productivity documents, in helping publishers manage who can open their content and how their content can be used or shared.

The benefits that AD RMS technologies provide can be classified into three categories: enterprise, end user, and IT.

Enterprise Benefits

The following benefits are most applicable to enterprises.

Prevention of Data/Information Leakage

The ability to protect intellectual property within Microsoft Office email messages and documents helps safeguard Microsoft corporate assets against accidental or intentional leakage. Only authorized consumers can decrypt and open rights-protected messages and documents. Unauthorized consumers cannot open encrypted content at all, whereas the document usage abilities of authorized consumers are limited to the rights settings that the publisher has assigned.

By helping to protect confidential business data, Microsoft and its business partners can feel more assured that the sensitive information that they create, along with related written reports and email discussions, will remain confidential.

Greater Sharing of Sensitive Information

The content protection of IRM reduces the risk of unintentional exposure of confidential materials. The data publishers' confidence, derived from that reduction of risk, enables them to take greater advantage of Office 2010, SharePoint websites, and file shares for disseminating sensitive business information. Because this information is available, recipients can make better, faster decisions, thereby improving business agility.

This confidence enables Microsoft and its business partners to use business-efficient means of transmitting confidential information between one another, such as email and secured intranet websites, to remain highly flexible and agile to respond to changing business and market conditions.

Application Support

AD RMS can be incorporated into both commercial applications and internally developed line-of-business (LOB) applications to help protect information. This solution enables the incorporation of protection across the entire range of corporate information. Microsoft IT, the team that has designed and implemented more than 1,500 internal LOB applications at Microsoft, is busy designing next-generation LOB applications that are AD RMS enabled to better safeguard confidential data. For more information about the AD RMS software development kits (SDKs), go to http://msdn.microsoft.com/en-us/library/cc530379(VS.85).aspx.

Common AD RMS Language

AD RMS technology uses Extensible Rights Markup Language (XrML) version 1.2.1 as the common language for expressing rights. This choice enables organizations to minimize the investment required to take advantage of AD RMS technology. XrML is a flexible, extensible, and interoperable standard that can meet any organization's needs, regardless of industry, platform, format, media type, business model, or delivery architecture.

XrML defines a language for expressing rights and conditions for the consumption of content in a way that is independent of the individual implementation. Although different types of content might have somewhat different interpretations of the exact actions that a specific right expressed in XrML should allow, the general meaning of the restrictions and the way to express them are not platform or product specific.

Using a standard certificate format enables AD RMS to be extended and to interoperate with third-party products, while helping to ensure compatibility as future versions of the platform and third-party solutions evolve.

End-User Benefits

The following benefits of offering AD RMS in the enterprise apply to end users.

Simple Tools for Users

Document publishers can assign usage policies to their content by using any application that is AD RMS enabled, such as Microsoft Office Professional Plus 2010, Office for Mac 2011, or any internally developed LOB application that is written to support AD RMS. Usage policies specify who can open the information, the specific rights assigned to each of the consumers, and how long those consumers can view or use the protected content. Specified users can open the rights-protected content with a simple click of a mouse, as they would any other file. Verification of usage policies happens without user awareness.

Powerful Document Protection Features

AD RMS technology enables persistent file-level protection, extending and enhancing existing network security efforts. Content owners can specify usage policies for their data, such as print, copy, and expire, giving them more features and options for protecting that information on the company intranet and in some extranet scenarios.

Ubiquitous Access

Rights-protected documents can be accessed from inside the network and from the Internet. Protected documents can also be created and consumed while the publisher is offline, and they can be stored in a mobile device's disk or in removable media with less danger of unauthorized access. Protected email can be created and consumed from any computer, even unmanaged computers, that can run any web browser that supports the full Outlook Web Access experience.

This ability gives authorized content publishers and consumers the freedom to keep accessing, creating, and managing documents from all their normal locations, while helping to keep information safe from unauthorized users.

IT Benefits

The use of AD RMS as the solution to help safeguard confidential data offers the following benefits to the enterprise IT department.

Ease of Implementation

With the release of AD RMS, Microsoft has focused on minimizing the effort that enterprises require to implement an IRM solution. Installing the AD RMS role is as easy as enabling other Windows Server 2008 R2 roles. Administrators can then connect it to other enterprise-critical servers such as those running Exchange Server, Microsoft SharePoint Server, and Windows Server with the File Classification Infrastructure (FCI) role installed, or to external services. They can build and enforce usage policies and establish trusted entities outside the organization.

AD RMS provides several possible ways to deploy either single-cluster configurations or a global, distributed AD RMS system topology. As a stateless web service, AD RMS can also be scaled up or out through standard and well-known technologies to meet enterprise growth needs.

Ease of Administration

Administrative features of AD RMS, such as revocation lists and exclusion policies, provide a enhanced level of control for sensitive and proprietary content at Microsoft. In addition, comprehensive logging enables Microsoft IT to monitor licensing activity, including granted and denied requests.

The general use of rights policy templates enables an enterprise to define and implement communication policies that are consistent across the organization and digitally enforced. AD RMS administrators design and control the content of the templates, and store them on the AD RMS servers for the enterprise publishing community to use. AD RMS administrators can easily modify the template definitions of approved consumers and the rights that are assigned to those users within a rights-protected document.

Templates offload the effort of determining who should be assigned user rights and what types of rights the intended consumer should receive from the publisher, simplifying the process that the publisher needs to follow. Furthermore, when modifications to a template occur, all past, present, and future content based on that template will inherit the new rights when a use license is issued.

Deployment of AD RMS at Microsoft

Microsoft IT differs from the IT organizations of other large enterprises in one significant way: It plays a significant role in the software development process as the "first and best customer" of Microsoft. In that role, Microsoft IT deploys Microsoft products in a production environment well before they are available to any other Microsoft enterprise partners and customers. In addition, Microsoft IT strives to be the model enterprise for deployment of those products. However, Microsoft IT does not deploy every Microsoft product. Rather, it focuses on products that are intended for large enterprise organizations and products for which a clear and compelling business case exists for deploying them within Microsoft.

Microsoft IT initially deployed Rights Management Services on top of Windows Server 2003. When AD RMS became available with Windows Server 2008, Microsoft IT updated the infrastructure to the new platform. Microsoft IT has since deployed AD RMS on Windows Server 2008 R2 with SP1.

Approach and Strategy

As with any major deployment in Microsoft IT, the key to success for the AD RMS deployment was careful planning. When deploying the initial version of RMS, Microsoft IT obtained topology diagrams, product specifications, hardware and scalability estimates, and other product documentation published by the RMS product group that could help plan the deployment and identify the hardware needs. The performance goals that Microsoft IT had for RMS 1.0 included less than 5 percent impact on network domain controllers and a completion rate of at least 95 percent of all licensing requests within five seconds.

Microsoft IT studied the projected network traffic that RMS would add to its infrastructure, based on deployment information that the RMS product group provided in the Deploy.chm file (a component of the RMS installation). The product group established a benchmark measurement of RMS by using a 1-gigahertz (GHz) Intel Pentium 4 server that had four processors and 1 gigabyte (GB) of random access memory (RAM). In this configuration, the RMS server delivered approximately 100 licenses per second.

the RMS product group provided the capacity planning figures in Table 4 for estimating the usage requirements for an RMS system.

Table 4. Estimated Usage Requirements for RMS

Transaction

Occurrence

Client-to-server bandwidth usage (kilobytes)

Server-to-client bandwidth usage (kilobytes)

License request

Repeated for every user and for every piece of content

22

10

RMS computer activation

AD RMS initialization traffic only

1

200

RMS account certification

AD RMS initialization traffic only

10

16

Client enrollment

AD RMS initialization traffic only

11

10

Microsoft IT also recognized that the Active Directory query traffic generated by RMS might potentially affect network throughput. However, Microsoft IT determined that this would not be a major factor if RMS servers were deployed in close proximity to the global catalogs. The exception would be if a failure of all global catalogs at a site caused a failover to another site over a connection that did not support the same capacity throughput.

Table 5 provides baseline data on the bandwidth usage of AD RMS transactions that an organization can use to assess the effect of Active Directory query traffic on a network.

Table 5. Baseline Data on Bandwidth Usage

Transaction

AD RMS to global catalog bandwidth usage (bytes)

Global catalog to AD RMS bandwidth usage (bytes)

AD RMS connection establishment (ldap_bind)

1,600

200

AD RMS group-membership evaluation (ldap_search)

200

100

Note: Numbers must be applied in context. For example, if the user belongs to 15 groups, 200 bytes would be required for the search request from AD RMS, and 1,500 bytes (100 bytes × 15) would be required for the response from the global catalog.

Analysis of the projected usage of RMS within Microsoft IT's network infrastructure showed the impact to be negligible. Table 6 illustrates the specific effects that RMS has had on the Microsoft corporate network.

Table 6. RMS Network Load Metrics Within Microsoft IT

Monitored site name

Average bytes sent

Maximum bytes sent

Average bytes received

Maximum bytes received

Number of requests

Computer Activation

511,687

39,698,882

1,974

139,646

226,508

User Certification

17,823

1,228,016

13,185

880,856

338,925

Publishing

18,242

325,430

19,532

305,515

136,927

Licensing

17,618

1,319,349

54,652

3,171,780

992,692

By using the information gathered during the planning phase, Microsoft IT decided on the deployment topology, the number and class of servers to order, and the service availability requirements.

In January 2003, Microsoft IT began preparations for its initial RMS deployment. Based on the projections of the RMS product group and the results of Microsoft IT lab testing, Microsoft IT predicted that approximately 2 percent of all email messages and attached business productivity documents sent within Microsoft would use IRM to enforce policy. Microsoft IT based this figure on its knowledge of its user base, the likelihood of the general population to adopt new technologies, and to what degree the new technology would be used within the company.

Note: The usage estimate figure will be different for each deployment, and each enterprise must project its own need for (and use of) AD RMS technology. After an enterprise makes this estimate, it can determine the capacity planning requirements.

Scalability test data provided by the RMS product group revealed that in the case of Microsoft IT, two standard-configuration servers would handle the load for all users in the company. This configuration included dual Intel Pentium 4 2.4-GHz computers with a 512-kilobyte (KB) Level-2 (L2) memory cache and 512 megabytes (MB) of RAM, set up as a load-balanced cluster pair.

To accommodate unanticipated usage growth, in addition to future expansion of RMS to LOB applications and other Microsoft and partner applications, Microsoft IT upgraded the RMS server specification to a four-processor, 2.4-GHz computer with 1 GB of RAM.

The corporate Active Directory infrastructure largely dictated the number of RMS server clusters that Microsoft IT needed to deploy. RMS, by design, initially checks the account logon forest for issuing RACs and licenses. To offer all user accounts access to RMS technologies, Microsoft IT deployed a load-balanced RMS cluster in all corporate network forests that contain user logon accounts. Besides the main corporate forest, three other forests are used with logon accounts at Microsoft, primarily for testing of cross-forest functionality of enterprise software and to isolate other developmental testing efforts.

To simplify administration and troubleshooting issues with RMS, Microsoft IT chose to route all document-publishing licensing requests to the RMS cluster for the main corporate forest. This forest contains more than 90 percent of all Microsoft logon accounts. Routing publishing license requests to the main corporate forest resulted in higher availability and scalability requirements than those of the other three logon forests. To meet the higher overall workload, Microsoft IT added a third, identically configured RMS server to the primary corporate logon load-balanced cluster for failover support in case of hardware failure. To accommodate future load, Microsoft IT expanded this configuration to four servers for the production forest as part of the migration to AD RMS in 2008.

Additionally, to meet its internal security requirements for protection of the RMS server's private key, Microsoft IT elected to include nCipher nShield hardware security modules (HSMs) on its RMS server specification.

Microsoft IT originally used Microsoft SQL Server 2000 database software for the required RMS transaction log database in each forest. Microsoft IT later migrated this to Microsoft SQL Server 2005 when it implemented AD RMS. SQL Server provides the ability to use transaction log shipping as a means to maintain a warm standby secondary server, as well as the option of using failover clusters for immediate failure resolution of hardware or system problems.

The final step in determining the deployment topology was identifying the connectivity methods for which Microsoft IT wanted to support RMS licensing. In particular, Microsoft IT determined that users must be able to obtain licenses while not logged on to the corporate network. Microsoft IT decided to place RMS behind servers running Microsoft Internet Security and Acceleration (ISA) Server, so that it could use externally accessible URLs for RMS servers.

Figure 1 illustrates the original RMS topology for the main corporate forest.

Figure 1. Original RMS topology for the main corporate forest

Figure 1. Original RMS topology for the main corporate forest

Architecture Enhancements

After Windows Server 2008 R2 was released, Microsoft IT made significant changes to the architecture of the AD RMS service.

Figure 2 illustrates the updated AD RMS topology for the main corporate forest.

Figure 2. AD RMS topology for the main corporate forest

Figure 2. AD RMS topology for the main corporate forest

Virtualization

To reduce the physical footprint and reduce costs, Microsoft IT replaced 50 percent of the physical servers with Hyper-V virtual machines. Microsoft IT configured the virtual machines with two virtual processors and 4 GB of RAM.

Network-Based HSMs

The original design called for individual physical servers, each with a Peripheral Component Interconnect (PCI)–based HSM installed and configured. Microsoft IT has since removed the individual HSMs and replaced them with network-based HSMs. Network-based HSMs enable Microsoft IT to add or remove capacity without requiring physical access to each server to configure the PCI HSMs.

Hardware Load Balancers

Microsoft migrated all clusters from using software-based load balancing to using hardware-based load balancing. This reduced the overall service complexity and allowed for distributing the load to servers that are in different subnets or physical locations in the data center.

Clustered Servers Running SQL Server

Microsoft IT moved the SQL Server databases from single SQL Server instances (one for each cluster) to a pair of clustered SQL Server instances to enhance reliability and service uptime. This change also allows patching and servicing of the servers without any service interruption.

Business Continuity and Disaster Recovery

Microsoft IT created a duplicate but scaled-down environment at a separate data center for disaster recovery and business continuity. The web servers in this environment are all virtual machines, whereas the servers running SQL Server are physical servers. The AD RMS servers use network-based HSMs for key processing.

Microsoft IT uses SQL Server log shipping to store a copy of the database at the remote disaster recovery site. This site is a warm backup, and completion of the failover process requires some manual steps.

Partnerships with Third Parties

Microsoft has established multiple partnerships with third parties to enable collaboration and a security-enhanced exchange of protected content. The process of establishing the AD RMS partnership is to export the trusted user domain (TUD) file from each cluster and exchange those files with the external company. After the files are imported into the AD RMS server, anonymous access must be enabled on the inetpub\wwwroot\_wmcs\licensing\license.asmx webpage. After both companies complete this process, users can use the built-in Outlook and Exchange Outlook Web Access "Do Not Forward" template to send protected email back and forth. A publisher can help protect other Microsoft Office documents by adding specific users by email address when he or she selects restricted access.

While Microsoft IT was running an initial pilot on the partnership scenario, it discovered that although exchanging only TUDs enabled the two companies to create and consume IRM-protected content from one another, the user experience was not satisfactory. Specifically, users received multiple credential and Internet Explorer trust notifications, which confused them. Microsoft IT created a set of scripts to run on computers at Microsoft, and it distributed these scripts to the partners to run on their computers. When users ran the scripts only once, their experience was then as seamless as it was opening content from local enterprise users.

Template Distribution

Beginning with Windows Vista SP1, a template distribution service allows the client to connect to the AD RMS server and download templates directly. To automate the distribution of templates, Microsoft IT has created a logon script that enables the template distribution service on the client and creates the appropriate Microsoft Office registry keys to point the client to the location of the locally downloaded templates.

Office 365

With the migration of on-premises mailboxes to mailboxes that are hosted in the cloud, Microsoft IT has enabled cloud-based users to continue to use IRM for content protection. The full IRM experience is available for Microsoft employees that use Outlook Web Access with Microsoft Office 365.

Monitoring

Microsoft IT monitors all AD RMS servers via the Active Directory Rights Management Services Management Pack for Microsoft System Center Operations Manager. The alerts are sent to a central console. From there, a support team is notified by email if an event occurs.

Microsoft IT monitors all HSMs by using Simple Network Management Protocol (SNMP) and a Windows PowerShell script. By using SNMP, Microsoft IT can monitor the HSMs for power-supply failures, high CPU usage, failed fans, or high-temperature warnings. If an issue arises, the script sends a notification to the support team.

Access from Unmanaged Computers

To support remote employees and users who use their personal computers (that is, computers that are not domain members) for work, Microsoft IT has created a user-executable script that will set the appropriate registry keys on the client and copy the AD RMS templates for use. After users run the script, they have full access to create and consume IRM-protected content. This script is available for users who do not have access to the corporate network and is placed on a site in the corporate extranet.

With the release of Windows Server 2008 R2 SP1, Office for Mac users can now take advantage of the Rights Management Service. Mac users who are off the corporate network can consume protected content by providing their corporate credentials when opening IRM-protected content. To create IRM-protected content, a Mac user must connect the computer to the corporate network once to generate a rights account certificate.

Current Usage Statistics

Microsoft IT generates monthly and daily reports on the growth and health of the service. These reports are generated on a central archive server that imports the relevant data from the servers running SQL Server on an hourly basis. The chart in Figure 3 is an example of the license growth over the past three years.

Figure 3. License growth over three years

Figure 3. License growth over three years

The charts in Figure 4 are examples of daily statistics gathered on the health of the AD RMS service.

daily statistics gathered on the health of the AD RMS service

daily statistics gathered on the health of the AD RMS service 2

daily statistics gathered on the health of the AD RMS service 3

Figure 4. Examples of daily health statistics for AD RMS

Exchange Prelicensing Deployment

No changes were necessary in the Microsoft Exchange infrastructure to enable basic AD RMS functionality. However, upgrading the Hub Transport Exchange servers to Microsoft Exchange Server 2010 permitted enabling Exchange Prelicensing. This functionality enabled consumers to automatically download licenses with protected content when using Outlook 2010 or Outlook Mobile in Windows Mobile 6.x. This functionality implies that the users do not have to acquire licenses or enter credentials at the moment of opening protected content that they received through email.

Although this change was visible to the users in the form of enhanced functionality, it required no user training and was implemented independently of the upgrade of the AD RMS servers to Windows Server 2008 R2.

Outlook Web Access

Before Exchange Server 2010, effective use of IRM protection was limited to Outlook clients. In Exchange Server 2007, Outlook Web Access users were required to download the Rights Management add-in for Internet Explorer so that they could access IRM-protected content.

In Exchange Server 2010, IRM in Microsoft Outlook Web App enables users to access the IRM functionality of Exchange to apply persistent IRM protection to messaging content without needing to install a browser plug-in. This feature extends to not only Internet Explorer, but also any browser that supports the full Outlook Web Access experience.

For more information, see "Understanding Information Rights Management in Outlook Web App" at http://technet.microsoft.com/en-us/library/dd876891.aspx.

Integration with SharePoint Server 2010

One of the most important new capabilities in AD RMS is the integration with Microsoft SharePoint Server 2010. SharePoint has always been able to store AD RMS–protected documents, because the protection capabilities are embedded in the document and not in the storage media. However, using IRM-protected documents with SharePoint used to imply a loss of functionality in the SharePoint server, because the contents of the protected documents were encrypted and obscure to the service, and the documents could not be tagged or indexed.

With AD RMS in Windows Server 2008 R2 and SharePoint Server 2010, this is no longer the case. The products include explicit support for this combination through the inclusion of the Office Protector component in SharePoint Server 2010 that allows for the automatic application of IRM policies to documents stored in libraries.

With SharePoint Server 2010, IRM is available for files that are located in document libraries and stored as attachments to list items. Site administrators can elect to use IRM to help protect downloads from a document library. When a user attempts to download a file from the library, SharePoint Server 2010 verifies that the user has permissions to the file, and it issues an IRM license to the user that enables access to the file at the appropriate permissions level. SharePoint Server 2010 then downloads the file to the user's computer in an encrypted, rights-managed file format.

After a farm administrator enables IRM for a farm, individual site administrators can enable IRM at the document-library level. Protection includes the following options:

  • Whether users can print documents that are rights managed.

  • Whether users can run Microsoft Visual Basic for Applications (VBA) and other custom code in the file.

  • The number of days for which the license is valid. After the specified number of days has passed, the license expires, and users must download the file again from the document library.

  • Whether to allow users to upload file types that do not support IRM.

  • Optionally, the date to stop restricting permissions to the document library. After the specified date passes, SharePoint Server 2010 removes all rights-management restrictions from the documents in the library.

SharePoint Server 2010 determines the user rights to assign based on the ACL entry of a user. If a user has access to the library, documents are delivered to the user with rights management applied. SharePoint Server 2010 allows access according on the options set for the library and according to the access level that the user has to the library.

Note, however, that all IRM-protected documents must be opened locally in Word (or another Microsoft Office application that supports IRM) and will be blocked from opening through Office Web Apps in the browser.

Figure 5 illustrates a typical document flow in SharePoint Server 2010 with AD RMS protection.

Figure 5. SharePoint protected document flow

Figure 5. SharePoint protected document flow

The steps of the document flow are as follows:

  1. A publisher posts a Microsoft Office document to a SharePoint document library that has AD RMS protection enabled.

  2. The document is stored in the SharePoint database unencrypted and unprotected. If the document as uploaded by the publisher was originally downloaded from the same library and is thus protected with IRM, existing protection is stripped before storage.

  3. A consumer who has read access to the documents in the library requests the document to the SharePoint server.

  4. The server retrieves the document from the database.

  5. The server uses the consumer's RAC and CLC to assign rights to the consumer to the requested document, depending on the consumer's rights on the documents in the library, with additional restrictions according to the policies established in the library. The server applies the rights to the document.

  6. The consumer receives the protected document. The requesting Microsoft Office application opens the document with the help of the AD RMS client and with the rights that the policy has defined.

The whole process occurs automatically and does not require special input from either user. The platform provides assurance that the documents will always be protected according to the policies that are defined for the library.

File Storage in SharePoint Server 2010

Because companies often have restrictions that require their files to be stored in unencrypted formats, SharePoint Server 2010 does not store files in encrypted, rights-managed file formats. However, SharePoint Server 2010 calls an IRM protector to convert stored Microsoft Office documents to an encrypted format each time a user downloads the file. The model is extensible, and protectors for other document types can be installed to automate the protection of different file formats. Similarly, when a user uploads a copy of a file that was previously rights protected by the same library, SharePoint Server 2010 calls the appropriate IRM protector to convert that copy to an unencrypted format before it is stored.

As a result, an organization does not need to create custom solutions to enable searching or archiving of document libraries where IRM is enabled. Storing the files in unencrypted format ensures that the current Search indexing service can crawl content stored on the servers.

Microsoft uses extensively the search capabilities of SharePoint Server 2010. Combining this discoverability with the ability of the platform to keep the documents protected after delivery to consumers is an excellent solution to deliver flexible access to information without compromising confidentiality or privacy. With SharePoint Server 2010, search results are scoped to user permissions, so users never see search results that include content to which they do not have some level of access.

Deployment of the integration between AD RMS and SharePoint Server 2010 was straightforward. The owners of each SharePoint Site implemented the deployment on top of SharePoint Server 2010. Implementation involved enabling AD RMS in each library to be protected and setting the AD RMS cluster properties for the SharePoint server. Administrators of the SharePoint sites can make these changes as they see the need for additional document protection.

Integration with FCI

To help protect file shares that contain documents with high business impact (HBI) data or personally identifiable information, Microsoft IT uses AD RMS to encrypt these documents with the AD RMS bulk protection tool and the FCI role installed. Microsoft IT created a set of regular expressions to search through the documents and identify matching strings of text that would classify the data as HBI.

Service and Support

The additional support requirements for implementing AD RMS and IRM at Microsoft were minimal. The reasons for the minimal support requirements were as follows:

  • ·The Microsoft IT end-user support teams absorbed AD RMS end-user support duties. The implementation did not require any additional support personnel.

  • The Identity and Access Management (IDM) team in Microsoft IT absorbed AD RMS server administration duties. The implementation did not require any additional administrator personnel.

  • The AD RMS SQL Server databases were backed up through the existing SQL Server support infrastructure. The implementation did not require any additional infrastructure.

  • The AD RMS server infrastructure uses System Center Operations Manager for server monitoring and the AD RMS–specific management pack for System Center Operations Manager. The AD RMS development team created the new management pack specifically for monitoring the status of AD RMS servers and activity on those servers.

Microsoft IT receives an average of 50 support calls per month related to AD RMS and IRM. The Microsoft Helpdesk handled and closed approximately 80 percent of those calls. The number of calls related to AD RMS and IRM is minimal, considering that Helpdesk receives an average of approximately 11,000 calls per week. Approximately two-thirds of the calls that Microsoft IT received were resolved as either issues related to user training or issues not specifically related to AD RMS.

Microsoft IT assigned administration of the AD RMS infrastructure to the IDM organization. This organization is also responsible for the day-to-day operations of Active Directory Certificate Services (AD CS) and AD FS, and for providing continuous, year-round support.

Training

To educate the Helpdesk and other support staff for AD RMS and IRM, Microsoft IT used deployment guides and product help available from the Microsoft Office and AD RMS product groups. These materials consisted mainly of the publicly available Microsoft Office and AD RMS deployment guides. Microsoft IT presented these materials to the Helpdesk staff in a single, one-hour-long session for each shift. Additionally, Microsoft IT subject matter experts wrote several Knowledge Base articles for the Helpdesk and end-user support teams to use. Microsoft IT did not conduct any further support-team training specifically about AD RMS and IRM, in part to validate the ease with which AD RMS and IRM can be deployed in an enterprise.

Microsoft IT also produced and published user training, in the form of an informational email message and online content. As with the training materials for the support teams, Microsoft IT produced this content primarily from materials that the Microsoft Office and AD RMS product groups made available.

Employing Super Users for Document Recovery

Document recovery is a key area of support in the Microsoft IT environment. AD RMS enables Microsoft IT to have a person or team of people assigned membership in an AD RMS Super User distribution group for efficient document recovery. If AD RMS rights are applied to a key document and the publisher subsequently becomes unavailable or leaves the company before the policies can be removed, the Super User group can enable the editing or complete removal of the policies that the original publisher set. Microsoft IT has limited membership in the Super User group to a small number of highly trusted individuals. In addition, only in specifically defined business cases can a member of the Super User group intervene to annul the policies of a rights-protected document.

Having a means to remove publisher-assigned policies is sound corporate policy. Like most businesses and organizations, Microsoft considers all intellectual material that employees create at work by using its corporate network and computing resources to be Microsoft property. Microsoft must retain the ability to recover its property if, for example, a malicious user intentionally use IRM policies to protect a document. Additionally, the ability to recover rights-protected documents is necessary for legal reasons in cases of discoverability in a court of law.

A member of the Super User distribution group on an AD RMS server is automatically assigned full control rights to any rights-protected content published by that server. To ensure that this trust is not abused, Microsoft IT has specific business processes in place for when Super User permissions are used to open any rights-protected email messages and documents.

The IDM team within Microsoft IT is responsible for the Super User distribution group and manages the membership of that group.

Note: The Super User feature should be left disabled until it is needed. At that time, it can be temporarily enabled, used as required, and then disabled again. This ability allows for tighter control by requiring a specific request to trigger the use of Super User permissions only when they are needed.

Lessons Learned and Best Practices

By thoroughly evaluating and deploying an AD RMS server infrastructure and using the IRM client technology in Office Enterprise 2010, Microsoft IT learned several valuable lessons that can be applied as best practices in most other AD RMS/IRM deployment plans. Microsoft IT learned some of these lessons and best practices during deployment, and some as outcomes of the deployment. They can be divided into three general categories: deployment, security, and administration.

Deployment

Microsoft IT derived the following lessons and best practices from its experience in deploying AD RMS and IRM.

Educate Users

To take full advantage of the technology, users must be told that the service exists and taught how to properly use it. An organization can educate users by creating self-help training content and knowledge base articles, developing a dedicated intranet website for posting training materials and frequently asked questions (FAQ), and regularly advertising and discussing the service addition with employees during the deployment. Successfully informing users about where to find the information that they need to properly use the service will minimize the effect on the help desk.

Run a Pilot

An organization should introduce AD RMS to the enterprise in a pilot deployment project with a limited set of users in a small, controlled area. During the pilot, the organization should test all of the desired usage scenarios, including any planned templates.

After successful completion of the first pilot, if the organization expects the size of the eventual rollout to include a very large number of users, it should conduct a second pilot to a larger (but still closely monitored) group of users. After identifying and considering scaling issues, the organization should begin the rollout to the rest of the organization, as resources and time permit.

Employees who are running versions of Microsoft Office older than Office Professional Edition 2003 or editions of Microsoft Office that do not support IRM directly can use RMA as needed to read rights-protected email and documents prior to their own upgrade to IRM-enabled versions of Microsoft Office. This capability must be specifically enabled in the rights policies applied to the documents, so the organization should set it up in the policy templates during the deployment period.

At Microsoft, Microsoft IT sent rights-protected email to successively larger groups of consumers simultaneously, to stress test the AD RMS licensing infrastructure. Microsoft IT considered the deployment of AD RMS and IRM officially complete when it successfully sent a rights-protected email message to the distribution group that encompasses all Microsoft employees, and all valid consumers were able to read it.

Consider Network Bandwidth

An organization should carefully consider constraints in network bandwidth before adding new services to the existing core IT services. It is likely that the network was designed with different assumptions, necessitating the careful management of the risk of business disruption. Microsoft IT's experience in deploying AD RMS technology with a new server infrastructure and license distribution demonstrated that the Microsoft corporate network bandwidth was not significantly affected.

Deploy All AD RMS Servers with a Failover Option

All servers that support AD RMS in a forest should be deployed with at least two servers to support server failover in case of catastrophic hardware failure. This advice also includes the AD RMS transaction logging servers, which are used with every AD RMS transaction.

Use Configuration GPO to Enforce Corporate Settings

At Microsoft, users of Microsoft Office might install it from distribution servers that Microsoft IT does not manage (such as the distribution servers that the Microsoft Office development team uses internally). As a result, Microsoft IT had to use a Group Policy Object to deploy a change in the client registry. This script allows for the automated download of the IRM templates and sets the appropriate Microsoft Office registry keys.

Consolidate Licensing Across Forests

With Active Directory infrastructures encompassing multiple forests, an organization should use an load-balanced cluster for AD RMS certification in one forest to serve publishing and licensing requests for the entire enterprise. This action simplifies administration tasks and minimizes troubleshooting work when all publication licenses come from the same source. The organization should deploy registry keys to users from other forests to point them to this cluster. It should use AD RMS clusters on the other forests only for expansion of distribution lists and account activation.

Security

Microsoft derived the following security lessons and best practices from its experience in implementing and managing AD RMS and IRM.

Do Not Use SQL Server Authentication Mode

For the highest level of security, an organization should not configure the SQL Server database servers on the AD RMS infrastructure to support SQL Server authentication. In SQL Server authentication mode, credentials are passed in plaintext in the connection string, so SQL Server should be configured to support only Windows authentication.

Enforce Access Restrictions

An organization should ensure that only those personnel who need to administer AD RMS have:

  • Membership in the Administrators or AD RMS Service Group local groups on the AD RMS server.

  • The Log on Locally permission on the AD RMS servers.

  • Terminal Services user access on the Remote Desktop Protocol (RDP) connection configuration on the AD RMS servers.

In addition, the organization should ensure that the discretionary access control lists (DACLs) that are configured for the servers restrict access to only essential personnel.

To support group expansion across forests, AD RMS automatically assigns read access to directory services to all authenticated users who have domain credentials. To increase security, the organization should remove this access from the DACL and replace it with each service account that is in the different forests.

Help Secure SQL Server Databases

Allowing unprotected database communications is a high security risk. To help prevent malicious users from capturing or modifying logged data, an organization should help secure SQL Server databases by configuring either SSL or Internet Protocol security (IPsec) to provide encrypted channels.

Do Not Deploy Any Additional Services on AD RMS Servers

After provisioning AD RMS on a server, an organization should not use this server to run any websites or additional services. If services other than the AD RMS services run on AD RMS servers, conflicts that can result in security issues may occur. Isolating AD RMS on its own dedicated servers helped Microsoft IT predict and manage workload. Isolation also prevented the introduction of software incompatibilities that may have compromised the integrity or functionality of the AD RMS service.

Create a Dedicated User Account to Use as the AD RMS Service Account

For security reasons, an organization should create a special user account for use as the AD RMS service account. The organization should not use this account for any other purpose and should not give the account any additional permissions. It should add the AD RMS Service group to the IIS_WPG group on the domain controller. Membership in the IIS_WPG group is required for running the AD RMS application pool (_DRMSAppPool1).

Use an HSM to Help Protect Private Keys

Instead of using software encryption, an organization should use a hardware security module to help protect AD RMS private keys. Using an HSM improves the security of private keys by keeping private keys in tamper-resistant hardware and never exposing them to software-based attacks.

Use Groups to Manage Access to AD RMS Administration

An organization should add members to the AD RMS Enterprise Administrators, AD RMS Auditors, or AD RMS Template Administrators groups, identifying those domain users or domain Global groups that are responsible for administering AD RMS, instead of adding them to the local Administrators group in the AD RMS server.

Note: If AD RMS is running on a domain controller, an organization must add the AD RMS service account to the Domain Administrators group. The organization should not add the AD RMS service account to the Enterprise Administrators group.

For even higher security, the organization should remove the domain users from the local Users group on the AD RMS servers, and then add the users and groups who are members of the AD RMS Service group to the local Guests group.

Administration

Microsoft IT derived the following lessons and best practices from its experience in managing and administering AD RMS and IRM.

Centralize Servers in a Single Location

It is a best practice to centralize AD RMS server deployment as much as possible (within the known constraints of link reliability and network bandwidth). Centralizing the AD RMS servers simplified server administration duties for Microsoft IT.

Prepare for AD RMS Server Monitoring Issues

The Active Directory Rights Management Services Management Pack for System Center Operations Manager manages the logical parts of AD RMS that an operator or administrator is interested in monitoring, configuring, or reporting on. The management pack includes monitoring capabilities on AD RMS deployment, AD RMS web services, and the AD RMS logging service.

In the information that the management pack reports, the following colors indicate health states:

  • Green: Normal operation.

  • Yellow: Degraded operation.

  • Red: Failure.

Each health state is related to an operation or the type of functionality that a managed entity is designed to perform. Detection rules detect health states.

Although the Active Directory Rights Management Services Management Pack can detect transitions to specific health states, not all rules in the management pack have been designed to take advantage of the State feature of Operations Manager. In these cases, transitions to specific health states are exposed only through the generation of alerts, and the relevant change in health state is not reflected on the AD RMS role and related state views.

For more information about the Active Directory Rights Management Services Management Pack, refer to the Monitoring Scenarios page in the Windows Server 2008 Technical Library at http://technet.microsoft.com/en-us/library/cc468596.aspx.

For more information about the errors and events that AD RMS records, refer to the Events and Errors page for AD RMS in the Windows Server 2008 Technical Library at http://technet.microsoft.com/en-us/library/cc771924.aspx.

Monitor the Size of the Logging Message Queue

An organization should use System Monitor to regularly monitor the size of the outbound logging message queue. If the queue size grows substantially, the organization should verify that the logging listener service is operating correctly. If a malicious user causes the logging listener service to stop, the outbound logging message queue will grow and eventually exceed the disk space of the AD RMS server. If this occurs, the server will deny requests.

Manage Growth in the Logging Database

Every AD RMS licensing request that the Microsoft IT AD RMS servers receive is logged in the AD RMS SQL Server database. The usage of AD RMS and IRM within Microsoft during the pilot and initial full deployment stages was generating growth in the logging database of about 1 GB per week, with a projection of 1 GB per day after actual usage estimates were realized. To reduce the volume of data to be logged, Microsoft IT later changed the logging configuration so that only critical events and necessary performance data were recorded by default. Microsoft IT enables higher logging settings only when necessary for research or troubleshooting.

To aggregate logging data from the various AD RMS clusters, Microsoft IT developed a series of scripts and created a secondary, separate database to serve as a logging database archive. The scripts extract from each cluster the data that is most relevant for usage reporting and store it in a single centralized database. Microsoft IT also implemented a script that keeps only the past 30 days of raw data on a rolling basis within the live AD RMS logging database. Any older data is archived to the Microsoft IT–developed database.

The "request duration" record for each AD RMS transaction is one of the best performance indicators, because it gives an overall indication of the load and efficiency of the servers and of the user experience. AD RMS also provides Windows performance counters that record the average number of transactions processed during the past second and the number of long-running transactions. Microsoft IT collects the performance counters only during research or troubleshooting activities, with no permanent storage for historical counters.

Microsoft IT uses SQL Server Reporting Services to automatically produce—daily and on demand—reports of AD RMS usage, status, and performance. Among the most useful reports are request volume by type, frequency and distribution of licensing errors by type, and average request duration by hour. Microsoft IT uses these reports to assess the health and performance of the AD RMS infrastructure and to plan proactive maintenance and expansion.

Develop Policy Templates

AD RMS templates, such as those that Microsoft IT created for use with Office Enterprise 2010, enable enterprises to define what types of official, global AD RMS policies they want their staff to use as publishers of confidential content. Templates can be made to help protect company confidential content, attorney/client privileged content, business partner content, and more. The IT group of any large enterprise organization should involve the corporate legal and security teams in brainstorming what is needed to enforce corporate communication policies.

Perform Frequent Backups of the Configuration Databases

The configuration databases store information that is vital to the functioning of AD RMS. In addition, the load-balanced AD RMS cluster configuration database stores the key pairs for the entire installation. If an organization performs regular backups, it can quickly restore AD RMS if a database server fails.

Any enterprise that is deploying AD RMS should have, at a minimum, a log-shipped secondary (warm standby backup) server available in case the shared disk drive storage in the load-balanced AD RMS cluster has a catastrophic failure. A warm standby server will enable the IT team to recover AD RMS service with a minimum of delay.

Microsoft IT backs up its logs every 15 minutes. In a worst-case scenario, Microsoft IT can restore the databases to within three minutes of the failure, minimizing the effect of a service outage.

Conclusion

Microsoft benefited from the deployment of the AD RMS server infrastructure and its counterpart, IRM, within Office Enterprise 2010 in several ways. Publishers can use IRM to assign unique user rights for Microsoft Office documents to separate individuals and distribution groups. IRM helps protect the confidential contents of business email and Microsoft Office documents from unintended consumers through the use of 128-bit encryption, can limit the time that protected content can be opened, and enables publishers to define—at a highly detailed level—how their content can be used or shared. AD RMS enables an organization to create rights policy templates that provide a uniform way to help protect sensitive information.

At the same time, as evidenced by the ever-growing IRM usage numbers in Microsoft IT, AD RMS and IRM have filled an important data-protection gap for Microsoft staff. Many groups within Microsoft IT, in addition to the legal and human resources departments at Microsoft, have begun adopting AD RMS and IRM in lieu of other, older alternatives, such as S/MIME. This adoption is due in large part to the setup and usability features in Office Enterprise 2010, as well as the configuration work that Microsoft IT completed to make the installation of IRM seamless to Microsoft users. The support data that Microsoft IT gathered further reflects the ease of use of these products and the relatively small administrative burden that AD RMS has introduced on the Microsoft corporate network infrastructure.

For More Information

For more information about Microsoft products or services, call the Microsoft Sales Information Center at (800) 426-9400. In Canada, call the Microsoft Canada information Centre at (800) 563-9048. Outside the 50 United States and Canada, please contact your local Microsoft subsidiary. To access information through the World Wide Web, go to:

http://www.microsoft.com

http://www.microsoft.com/technet/itshowcase

This is a preliminary document and may be changed substantially prior to final commercial release of the software described herein.

The information contained in this document represents the current view of Microsoft Corporation on the issues discussed as of the date of publication. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information presented after the date of publication.

This White Paper is for informational purposes only. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED, OR STATUTORY, AS TO THE INFORMATION IN THIS DOCUMENT.

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