Virtualisation Comes to the WAN Acceleration Market

Virtualisation is making new demands on WAN acceleration and optimisation. Richard Chirgwin looks at how they are responding to these nw challenges.

For some classes of vendor, the twin trends of virtualisation and cloud computing look like a mixed blessing - more stuff moving into data centres creates a new sales opportunity, but if the clouds end up as efficient as they're meant to be, they'll buy less iron to get a given amount of horsepower, while at the same time reducing the end users' reliance on their own servers.

But for the WAN acceleration segment, the drive towards cloud computing is nothing but good news. The first question for someone considering moving an application from local servers into either a private or public cloud i how to do so without condemning their users to slow application responses and lost productivity. So SearchNetworking ANZ took the opportunity to speak with two WAN acceleration vendors, Riverbed Technology and Expand Networks, both of which are targeting the virtualised environment, to hear what cloud providers and their customers want out of their technologies.

In both cases, the move to virtualised products represents a huge shift in the portfolio, since what once shipped as a piece of iron is becoming a disk image. So what prompted such a radical approach?

Performance inhibiting the cloud

The basis of the WAN acceleration pitch is simple, and arguably even more compelling than it was when the market first emerged in the late 1990s. While everybody would agree that the branch office should be able to get fast access to files and/or documents held at head office, everybody also understands that a regional bank branch, 250 km from the nearest capital city and connected over a 512 Kbps Frame Relay link will suffer some delays. However, if the document is being opened in a local application, the user experiences a wait for a download, but application performance doesn't take a hit.

Move the application into the cloud, and a branch office using a slower connection than head office will suffer a hit to application performance all the time.

"Performance is the problem," said Steve Dixon, Australia and New Zealand managing director for Riverbed Technologies. "Your applications are no longer under your control, and with the bandwidth and latencies and so on, there's likely to be a big performance hit."

This stands in the way of companies deploying applications into the cloud if those applications are in constant use across their staff. "If we can say 'you will still get LAN-like performance', it removes a big obstacle from the venture," Dixon said.

Steve O'Brien, Expand Networks' VP for APAC, says end user psychology creates an expectation that performance is at risk. "It's similar to the experience when companies first started consolidating their servers," he said. "People were accustomed to doing their work on a server that was near their desks - when you removed the server, they expected a degradation of their service."

Maintaining the best possible performance for users accessing applications in the cloud, O'Brien said, "is paramount to ensuring a wholesale adoption of those kinds of services."

Virtualising the WAN accelerator

Both Dixon and O'Brien agree that they're now seeing growing customer interest in the cloud environment, and the associated move towards implementing virtualised server environments.

"Australia has been very aggressive in virtualising the data centres," O'Brien said. "When you look at Australia, the limited infrastructure and the distances involved - Australians are looking to use [virtualisation] technology not only for competitive advantage, but because it makes economic sense."

Dixon says that as infrastructure-as-a-service, software-as-a-service and storage-as-a-service take off, the technology decisions move away from the end user. "You aren't determining the platform the service resides on - you're buying access to the service and a service level. It's up to the provider to determine what they use, which is what's leading them to virtualisation. It's a critical component for these service providers."

As the cloud providers cut down on the number of servers they need by virtualising their own environments, network infrastructure starts to stand out: why would the cloud provider tolerate the multiplication of network appliances while at the same time reducing the number of servers they need?

This has brought about a radical shift in the way WAN accelerators are delivered. What was once a dedicated pizza box can now be delivered as a software image, loaded up as a virtual machine in VMWare, and fit in with the Occam's razor of the data centre, to avoid the needless duplication of entities.

"People are reluctant to just get more racks of different appliances from vendors - to need to configure them, enable them for some clients but not others, and so on," Dixon said.

O'Brien agrees, saying that "the concept of putting new network appliances into the data centre when you've just finished taking other equipment out of it seems counter-intuitive."

Virtualising the WAN acceleration environment also creates opportunities for the vendors to address other requirements of the cloud providers - in particular, to align not just the deployment to the provider's business model, but also how the acceleration system is managed.

"The cloud provider could offer this as an additional service. They might want the ability to enable an optimised link, and the opportunity to differentiate services by providing different levels of services," Dixon explained.

"Virtualising the accelerator means the provider can be selective about who uses it, while at the same time reducing th provider's overheads and reducing or removing their performance limitations."

O'Brien points out that virtualising systems in the data centre can also free up assets customers already own.

"Australian companies aren't so aggressive in virtualising their branch offices - but one thing they can do is redeploy their appliances from the data centre out to the branch. And with the Virtual Accelerator, they can redeploy equipment that was earmarked for disposal to get a very cheap acceleration solution for their branch offices."

The pitch in the cloud

It's no surprise, then, that the WAN acceleration segment has the data centre and cloud provider market firmly in its marketing sights for 2010.

On the vendor side, the advantage is simple: as cloud computing takes off, the cloud providers have the potential to act as a multiplier for the customers. Once a particular technology is adopted in the cloud, there's a reason for the end user to adopt the same technology. Dixon: "The strategy is simple - go to the cloud providers first, then go to the customers and let them know that they can get the benefits of optimisation.

"And we can help the service provider overcome performance concerns."

O'Brien said Expand will be looking to attract cloud providers for similar reasons, and in 2010, the company will be announcing a partner program designed for that segment of the market. The more important cloud providers become, the more important they will be as a channel for the WAN acceleration vendors as well.

Another attraction is one of scale - there are hundreds of large enterprises in Australia, thousands of medium, and tens of thousands of SMEs large enough to justify at least entry-level WAN acceleration. Leveraging the much more constrained cloud services market to reach its end users is an attractive and intelligent marketing strategy.


With this emerging and potentially lucrative market on offer, both vendors are keen to pitch their key differentiators.

Dixon stresses two aspects of the Riverbed environment: it operates on an "any-to-many" basis, with "no real limits on how many devices you can connect to the network", and its ability to run a single dictionary in very large environments.

The dictionary is one of the core technologies in Riverbed's WAN optimisation: it indexes data sent over the network, so as to eliminate the duplication of data in the network. To take a trivial example, if a user opens a document, edits the document, and then closes it, there's no need to transmit over the network any information that remains unchanged.

"If you have to create an individual dictionary for every connection, every peer, every tunnel over the network ... the efficiency falls and your available memory falls."

Dixon believes this gives Riverbed a position it can leverage as it addresses the storage-as-a-service market with its iSCSI optimisation capabilities. Because the data traversing storage networks can be so highly duplicated, "we see some phenomenal levels of data reduction".

O'Brien stresses the range of deployment options in the Expand environment, something which he says gives the company reach downwards to smaller customers. "There's a huge number of SMEs in Australia who can't afford the top-end large enterprise appliances."

That segment, O'Brien said, will become increasingly attracted to cloud services, since for the SME, a successful cloud deployment eliminates a host of headaches associated with owning and operating the burgeoning number of servers needed to keep a business operational.

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