GCN LAB REVIEWS
NetScaler load balancer can squash network latency
Appliance helps direct users to the best performing sites on the network
- By Carlos A. Soto
- May 05, 2011
Nothing’s more frustrating than network lag. About 10 years ago, latency was tolerated as the norm. About five years ago, it was occasionally expected. Nowadays, you’d be hard pressed to find a person who didn’t abhor the thought of having to wait a few minutes after clicking a link or typing in a website address.
Although feelings about network latency are one thing to users, the ramifications to agencies that suffer from network outages or latency can be disastrous.
Experiencing lag or downed network services in your organization is like finding a rat in a restaurant. The immediate reaction of most people to any kind of network problem is to question the competence of the organization and stay away from the site in the future. Most organizations spend a lot of money, human effort and time maintaining, upgrading and testing their networks to ensure that will never happen.
Fortunately, this hard work pays off. Encountering latent or downed networks is now rare. That’s because keeping networks up, although expensive and laborious, is no longer rocket science. In fact, there are only a few main reasons to explain why a network would go down or experience latency. An environmental disaster might have occurred or perhaps poor procedural planning, execution or budgeting. In any case, correct planning can fix all of those problems — even the consequences of a natural disaster — by anticipating the need for proper redundancy.
Citrix NetScaler MPX 9700
Pros: More than a dozen robust features and strong performance.
Cons: Difficult to learn; expensive.
Features: A +
Ease of use: B-
Price: $39,311 (General Services Administration price, as configured for test)
Steelhead appliance takes latency out of the cloud
Protocol gives serious speed to Web apps
To avoid such problems, proper planning and the right equipment in your network are key. However, you need more than just servers. To get the job right, a good load balancer, such as the Citrix NetScaler MPX 9700, could mean the difference between up or down for any network.
The Citrix NetScaler is much more than a load balancer; it’s really an all-in-one Web application delivery system that makes applications run many times better by ensuring server availability. It does this through advanced traffic management by identifying content in the layers of a network packet. As a solution, NetScaler also increases security with an integrated application firewall. It can also lower costs substantially by offloading stressed servers and thus easing maintenance-related expenses.
The best word to describe NetScaler is scalability. For geographically distributed agencies, NetScaler’s Global Server Load Balancing feature helps direct users to the best-performing site on the network. In addition, through the use of its proprietary Metric Exchange Protocol (MEP), NetScaler offers a line of sight into which server farm or location is performing at its peak.
MEP, a protocol exclusive to Citrix appliances, is crucial to ensuring the availability of data centers by checking their health and status. It works by finding when the data center with a lower IP address initiates a connection with the data center with a higher IP address.
Although it’s easy to get bogged down in the deep technical details of NetScaler, especially with larger installations, its list of features makes it worth the effort to learn. In fact, although it took us a month to get up-to-speed with the software, it was time well spent.
NetScaler can accelerate application performance by five times the norm through static and dynamic content caching, compression and wide-area network protocol optimization. That includes the ability to offload Secure Sockets Layer processing from servers, which is especially important for Web 2.0 applications.
An end-to-end approach to application security includes an integrated Access Gateway Enterprise feature for secure remote access and an application firewall for protection against application layer attacks. And the AppExpert Visual Policy Builder is a fully graphical user interface-based tool that makes it a little easier to configure all features with a common look and feel.
Several application templates and multiple wizards add to ease of use and help build a comfort level with some of the more intimidating features of these devices.
Advanced TCP optimization technologies also improve the performance of the underlying network infrastructure so that applications are delivered to clients at a faster rate.
An application cache that delivers as much as 16G of in-memory content caching for static and dynamically generated application data adds to this set of features. This cache has the potential for reducing the time needed to run reports and serve frequently accessed content. Finally, application compression can decrease the size of data traveling via HTTP, which speeds the delivery of content to users and further reduces lag or latency.
Starting at about $39,311 per unit for a basic appliance model, the NetScaler goes from pricey to incredibly expensive in no time. However, the fact that it is also available as a virtual appliance makes the choices easier for most groups based on their budgets. With the NetScaler VPX virtual appliance, NetScaler can now be deployed on servers anywhere in the data center. As a result, NetScaler MPX can be easily deployed on-demand anywhere in the data center or cloud environment. It took some serious training time to get up-to-speed, but now I would feel naked trying to deploy a domain without a NetScaler load balancer.
Citrix Systems, www.citrix.com