May 5th, 2011 |
A post from Bob Gilbert, Evangelist of Riverbed Technology
The value propositions promised by cloud computing are undeniable. Pay only for what you need. Elastic capacity. Lower entry cost and more efficiency. While the market continues to be educated on how the cloud can deliver tremendous value, the concern about security seems to always be the top consideration when it comes to taking advantage of what the cloud has to offer. How do you ensure that your company’s sensitive data is protected when you move it to the cloud? While security has been a top cloud computing concern, availability has stepped up the consideration list obviously driven by Amazon’s recent failure event with their EC2 platform.
The good news is that cloud-computing vendors are making great strides in addressing the concerns over security and availability. Amazon for example, did a nice job addressing their recent service disruption issue https://aws.amazon.com/message/65648/ and security concerns are constantly being addressed through a combination of both technology and education.
While security and availability is currently top of mind considerations for companies contemplating deploying cloud computing, there is one additional consideration that is less often discussed, but is arguably more important and that is performance. If you want to use the cloud to host your servers, applications, and storage, get ready to take a hit in access performance that is 5 times, 10 times, and in some cases 20 times or more slower than your existing infrastructure. That’s right. I said 20 times slower! All of the sudden, the value of cloud computing is faced with another barrier to entry.
What is the problem?
Is it the cloud computing vendor’s back-end infrastructure? Do they need faster hardware? The answer is no on both accounts. The performance hit is a combination of factors, but primarily the fact that users now need to go over a wide area network to access their servers, applications, and storage instead of a local area network. When their systems were on the LAN, operations would take a matter of seconds. Over the WAN, these same operations take minutes.
Can increasing bandwidth between the users and the cloud help?
Unfortunately, increasing the bandwidth connectivity between the users and the services in the cloud does not help that much. The bandwidth environment is typically shared between other users accessing the cloud provider. The result is asking straw problem that presents performance constraints caused congestion.
However, the biggest problem is latency/RTT. Applications such as email, file sharing, and web-based applications like Microsoft SharePoint require a ton of back and forth conversations to take place during the process of completing a data transfer operation. On a LAN with sub millisecond latency, these operations finish in a matter of seconds. Over a high latency WAN, each turn of the conversation incurs the penalty of the round trip time. Going cross-country, each turn could take a 10th of a second and if there are thousands of turns, operations can slow to a crawl. Operations that took seconds, now take minutes.
Improving cloud computing performance with WAN optimization
WAN optimization for several years has been a popular technology to optimize networks and accelerate applications for data centers, branch offices, and mobile worker environments. Cloud environments present some challenges for WAN optimization vendors that traditionally offer physical appliances. For one, you typically don’t have the keys to your cloud provider’s data center. Riverbed Technology addresses this with the Cloud Steelhead solution, which is deployed as a virtual platform that can seamlessly be deployed in various cloud computing environments. Riverbed’s Cloud Steelhead is also priced to be cloud friendly. Riverbed also offers the Whitewater cloud storage gateway product as a solution to enable lightning fast and efficient backup and restore to the public cloud.
The problem and solution spotlighted at Interop
To demonstrate the performance challenges with cloud, Riverbed is holding a Twitter contest during IT Expo at Interop. Riverbed is asking folks to guess how long it will take to copy a 50MB file from a cloud facility in Virginia to Riverbed’s booth at Interop. The guess should include the time for both with Riverbed and without. Riverbed will perform the live operation at their booth (#1927) at 2pm on Thursday and the entry that is closest wins a $500 Apple gift card. More details are here http://rvbd.ly/SpeedTheCloud
You can learn more about Riverbed’s presence at Interop here http://www.riverbed.com/us/company/news/press_releases/2011/press_050411_a
