Optimize wide area network performance for employees in branch offices with server computers

Published: November 4, 2009

Updated: November 4, 2009

Applies To: Windows Server 2008 R2


A connection between the main office and each branch office must exist before you deploy BranchCache.

This deployment goal is recommended for branch offices that contain one or more server computers. When you deploy BranchCache for employees in branch offices that contain client computers and one or more server computers:

  • Employees using computers that are running Windows 7 and that have BranchCache enabled can access content on your content servers at the main office; they can also access content that is cached locally by the hosted cache server at their branch office.

  • Free hard disk space is required on the hosted cache server, but no additional hard disk space is required on client computers, because BranchCache content is located on the hosted cache server rather than on client computers.

  • Depending on the types of content servers that you have deployed, employees can access many types of content at the local branch office rather than over the wide area network (WAN) link to the main office. This includes Web server content, files on a SharePoint server, training videos, software installation files (such as software patches and antivirus program signature updates), and file shares.

  • Due to reduced usage of the WAN, employees might see reduced application response times and improved application performance.

The following components are required for this deployment goal.

  • Content server. One or more content servers that are running Windows Server 2008 R2 and are located in the main office. Content servers can be file servers, application servers, or Web servers.

  • Hosted cache server. A hosted cache server must be installed at each branch office, and must be running Windows Server 2008 R2 with the BranchCache feature installed and enabled.

  • Free hard disk space on the hosted cache server. Free hard disk space on hosted cache servers at branch offices must be greater than the sum of the content plus the content information that is generated by the content servers. Content information is small in comparison to the actual content; you must reserve one byte of disk space for every 2,000 bytes of content that might be cached by the hosted cache server.

  • Certification authority. A certification authority (CA) must be used to enroll or autoenroll server certificates to hosted cache servers.

  • CA certificate. The certificate of the CA must be present in the Trusted Root Certification Authorities certificate store on client computers. This certificate allows client computers to trust the hosted cache server when retrieving content from the server.

  • Copy of the Web server certificate template. Using the Certificate Templates Microsoft Management Console (MMC) snap-in, you can configure a copy of the Web server certificate template for autoenrollment, allowing you to automatically issue, or enroll, a certificate to hosted cache servers that is based on the copy of the Web server certificate template.

  • Hosted cache server certificate. This certificate is issued by the CA to the hosted cache server, and is based on the Web server certificate template. The hosted cache server uses the certificate to prove its identity to client computers.

  • Client computers. One or more client computers that are running Windows 7 and are located in branch offices.

  • Group Policy BranchCache object. To enable BranchCache on Windows 7 client computers using Group Policy, you must first create a Group Policy object (GPO) that will carry the BranchCache configuration.

  • Group Policy client computer firewall configuration. The client firewall must be configured to allow incoming HTTP and WS-Discovery traffic on computers that use distributed cache mode.