Microsoft Exchange performs poorly on WANs – so much so that large enterprises often deploy distributed Exchange servers to support their local users. Maintaining many Exchange servers is expensive and complex, and often puts critical confidential data at risk. While most IT managers would prefer a centralized Exchange architecture, they face severe performance issues for their remote users.

By deploying Steelhead appliances, users in remote offices can access Exchange servers in a centralized and distant data center with roughly the same responsiveness as a local mail server. Distributing Steelhead Mobile on workers laptops can extend theses benefits even further by ensuring that email is accelerated regardless of where a user attempts to connect from. Riverbed can even help you avoid the early morning WAN congestion caused by the first log in of remote users. By pre-populating Steelhead appliances with users' email and attachments, there is virtually no incremental traffic when they log in first thing in the morning.

In addition to better performance, Riverbed’s SDR feature removes all redundancy from WAN traffic – including common email challenges like “reply to all” (which can plague WAN links by generating many copies of an email) and email with large attachments in which multiple copies of the file would otherwise be sent across the WAN, bringing other applications to a halt.

Fig 1: Send email with 6.3MB attachement to single recipient

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Application Layer Exchange Acceleration: Exchange 2010, 2007, and 2003

Riverbed was the first WAN optimization vendor to provide an application layer protocol optimization for Exchange 2003 for both office and mobile workers and has continued to improve the Riverbed Optimization System (RiOS) to bring Layer 7 optimization to Exchange 2003, 2007 and 2010. RiOS recognizes Exchange traffic in native mode and applies specific enhancements to significantly improve performance in both unencrypted and encrypted modes. Thousands of Riverbed customers have leveraged this optimization to consolidate their Microsoft Exchange servers without sacrificing performance for end users.