WAN optimisation has been atop the project list whiteboard for many data center managers. WAN connectivity is expensive. By optimising utilization of the WAN you can either lower your WAN connectivity bill or at least delay the need to upgrade it. WAN Optimisation is critical today, especially in storage.
It seems that every storage system, backup application and failover application has the potential to replicate data between data centers. Storage replication software used to be a significant investment that only the largest of data centers could afford. Now the functionality is often either included with the storage array or backup application at a minimal cost, making improved disaster recovery (DR) capabilities available to a broader range of applications and companies. The cost savings in functionality quickly erodes if you need to make a significant upgrade to your WAN links. While IT budgets are loosening, you have to still watch your expenditures as close as ever. WAN Optimisation allows you to add these types of capabilities to improve your ability to recover from disaster while not increasing you WAN expenses.
The challenge for WAN Optimisation vendors in the past is that they would deploy their software on appliances to ease the installation for network administrators. Many of the appliances though were not purpose built, they were simply off the shelf hardware from a server OEM that the WAN Optimisation vendor preloaded and preconfigured their software.
This gave the vendors some consistency in the hardware and made things easier to support. The challenge was that it was another brand of hardware to integrate into your data center. The vendors also quickly learned that even if they bought the same hardware from the same hardware vendor they still had to deal with changes to motherboards or network interface cards. The consistency they desired was not being delivered.
Enter virtual appliances. With virtual appliances WAN Optimisation vendors like Riverbed Technology, Silver Peak Systems, Certeon, Ipanema Technologies and NetEx now had a very consistent “hardware” platform. Certeon and NetEx have both earned the VMware Ready label. As a result these companies and others not only eliminate the challenge of having to deal with physical machines they gain all the advantages of the virtual environment. For example you now have the ability to move your WAN appliance between physical hosts in case of hardware maintenance or a need for more performance. You also don’t have to worry about having IT staff that understands WAN Optimisation to mount hardware in each remote location. For the vendors the “hardware” is now downloadable so you can more easily evaluate it. For customers you can easily “ship it.” It is also bundle-able meaning that WAN Optimisation vendors can partner with storage and backup software companies to deliver and all in one solution.
There is also some potential for Virtual WAN Optimisation and Cloud Storage. With hardware it would be difficult to offer a universal solution to thousands of potential customers. Virtual WAN Optimisation software could be part of the cloud storage download or integrated into the cloud gateway to make performance of cloud storage even better.
From a performance perspective most vendors are reporting results in the virtual versions of WAN Optimisation that leads me to believe that performance between dedicated hardware and shared hosts is going to be a wash for many data centers. Even if you decide to dedicate a virtual host to just the WAN Optimisation virtual appliance you still gain all the benefits of virtualization should you need them.