Having joined Windows Vista and Windows Server 2008 at the hip with the release of Service Pack 1 for both operating systems, Microsoft is moving on with this strategy for the next iterations of the Windows client and server platforms. The Redmond giant has synchronized the development processes of Windows 7 and Windows Server 2008 R2, and is also advertising the two products as a pair. In this context, BranchCache is one feature designed to make Windows 7 and Windows Server 2008 R2 an item.

“As the name suggests BranchCache helps IT administrators save on costs associated with WAN area network bandwidth by caching HTTP and SMB content at the branch office network. This not only saves on bandwidth costs, it also improves the branch end user's experience when accessing content and shares back at corpnet. BranchCache also accelerates the delivery of encrypted content, supporting protocols like HTTPS and IPsec,” explained Vikram Ghosh, Product Manager for Branch Office Solutions on the Windows Server Team.

BranchCache is a new feature Microsoft introduced in Windows Server 2008 R2, designed to work in conjunction only with Windows 7. BranchCache will enable frequently accessed content to be cached locally, freeing up bandwidth. According to Microsoft, the feature will cache content on a server in the branch office. At the same time, items can also be stored on client machines in the absence of a server. Microsoft informed that BranchCache is in no way limited to HTTP and SMB protocols. In fact, the feature has been set up to play nice even with Windows Media Player files, Internet Explorer, or Background Intelligent Transfer service (BITS).

“The content served to a request is always fresh, because when clients first issue an access request it always goes to the BranchCache server back at corpnet first. This serves not only authentication and access, but also lets the server send back content identifiers to the requester indicating if the file has been altered since the last time it was accessed. If those identifiers match content at the branch, then the content is served locally. If the content has changed and doesn't match the local cache, then a new version is shipped from corpnet. In distributed mode, these identifiers are sent out to other clients on the local branch network. If the branch has a server, also known as a hosted cache, then all cached data is stored there,” Ghosh added.