Crescendo's Web Application Performance Blog

• SLB -Since the appliance replaces a traditional load balancer, it has to take its basic functionality of load balancing among several servers. This is neither offload nor acceleration but is required as a legacy feature.
• TCP connection management and multiplexing—Even a strong server can be brought to its knees by making it deal with tens of thousands of TCP connections opening and closing rapidly. By handling all the myriad TCP issues on the client side and multiplexing the client requests into few well behaved TCP connections towards the server, a significant offload is achieved.
• Compression - Compressing web content is an established way of reducing bandwidth and reducing response time. Doing compression on the ADC offloads this task from the server.
• SSL - Secure Socket Layer is widely used for content encryption. Being computationally intensive, offloading it to the ADC can free up server resources.
• L7 advanced features - An advanced ADC allows the enforcement of policies such as traffic and content control based on L7 information. This allows complex data center behavior without burdening the servers.
• Caching - Most ADC’s consolidate a web caching feature in the device. This reduces load at the servers as cached content is served directly from the ADC.
• GSLB - Global Server Load Balancing allows balancing geographically separated sites based on their load.

In a recent webcast I talked about Crescendo’s Application Delivery Controllers (ADCs) and explained their usefulness in front-ending a web server farm. I started the conversation with an explanation about ADCs and how they load balance traffic but also help you offload heavy performance tasks from the servers. To illustrate this I showed a graph we did measuring server performance under traffic load.

 The graph shows a server handling traffic load created by an Avalanche traffic generator. Traffic rises to 6000 transactions per second (TPS) which the server handles very well. Once traffic rises above 6000 TPS, by a few 100 TPS, the results are catastrophic. The server drops traffic and response time shoots up dramatically.

Up to this point, this explanation is a numbers story. The story is about the threshold the server fails at. This seems like another technical explanation that skirts around the real issue but does not get to the heart of the matter. On a logical level it makes sense, but … so what?

Let’s look at it from another much more interesting perspective. Looking at the same issue from the business side, we can translate dropped connections to business lost - or very likely lost. The very large response times for the customers who do get service translates to frustrated customers and will very likely cause some of them to leave.

 

Looking at it from this perspective, the problem is very intuitive and one that every business must avoid. This is where a good ADC comes into the picture. On top of offloading work from the server and increasing its capacity, Crescendo’s ADC can automatically meter connections to the server and prevent flooding it. The result is that customers get predictable service at all times. The extra capacity the servers can handle with AppBeat DC will also help in cases of large crowd events like a big sale or promotion. In these cases, Crescendo’s ADC can be the conductor orchestrating all the servers to “sing”.

Take a look at the number of connections the same server can support when front ended with Crescendo’s AppBeat DC. The same server can now support 3 times the transactions. What this means is that when your next big sale comes around you can expect your cash registers to keep ringing.

 

Want to learn more about Crescendo’s AppBeat DC? Check out our video Intro to AppBeat DC.

For anyone living in the United States, July 4th – our Independence Day – is hard to miss.  Every year millions of Americans and businesses plan for this national event with retail sales, neighborhood and family gatherings, lots of barbequing and, of course, fireworks.

This year I had the opportunity to view an amazing fireworks display put on by our local themed amusement park.  As a viewer, I was wowed by the visual show - the colors, random heights and cadence of the display. But, as a marketing person for an ADC vendor who manages events as part of my job, I also have an appreciation for all the “behind the scenes” details that went into making this event a great customer experience – traffic flow, security, time management, etc. All of these things are necessary in order to pull off a killer event and guess what? They did.

Very soon, in just a few months, another major event will happen – the holiday season - the largest shopping season of the year. Customer expectations will be high and patience is usually low.  Now is the time that businesses should be thinking about planning for this end of year shopping blitz where the “behind the scenes” details will matter a lot.

Retail site users, like me, want our online shopping experience to be easy and fast. This means pages need to load quickly, my shopping cart must work properly and checkout should be secure and not hang! The good news is that there are solutions – Application Delivery Controllers - that can help retail sites achieve the predictability and fast page load time shoppers expect.  

With more shoppers every year opting to make some or all purchases online (like I do!), ensuring a good online customer experience will be critical to retaining customers and revenue in 2010. Learn more about ADCs by reading this white paper The Critical Role of an Application Delivery Controller.

Our tagline "Performance when it matters most" holds true - especially in the EDU market.

To an academic institution, this means your portal and e-learning site is fast and available - any slowdowns or outages can be disastrous, causing huge user frustration. Combine this with recurring events like student enrollment/registration that can dramatically increase load. Even if its only 4 times a year, you can't afford to take chances with your web services. But, predicting traffic surges is nearly impossible.

At Crescendo Networks, we know how to empower EDU sites for performance with unpredictable traffic. We can help you deliver fast, predictable applications under any load.

EDU customers like Rutgers University and Pierce College depend on our AppBeat DC application delivery controller for site performance and availability:

- Improved response times by up to 70%
- Ability to sustain traffic spikes at 10x the average load

Want to learn how much Crescendo's ADC can help your site? Test your site now with Crescendo's Performance Calculator.

If it's not, it's time to start evaluating options. Is your web site ready for 10X traffic? That is the benchmark that most IT professionals plan for around the holiday season. These are happy times that translate into big $$$$. Be sure you have a solution in place that will help you exceed revenue projections!!

So, how do you ensure your site is serving user requests fast and stays up and does not suffer from downtime? Application Delivery Controllers are a key part of a successful network infrastructure. To learn more about planning for unpredictable loads, read this new tech brief today.

Run a free test on your url to learn how Crescendo can help you optimize for the upcoming holiday season. If you need more information, our performance experts are also available to do a quick consultation at your convenience.

Don't wait - the clock is ticking!

2 weeks ago I participated in a cloud event called "Powering the Cloud". As much as it sounds like hype, the cloud is actually marching on. The most important fact that allows it to succeed is it's evolutionary nature to virtualization, not a disruptive revolution!

Virtualization has already gone mainstream where almost every IT organization is either using it or considering.

Data by Gartner suggests that via virtualization, organizations can fundamentally change their server to admin ratios - from 20-30 to 1 in the physical world to 60-100 to 1 in the virtual world. The IT world agrees.

Cloud is supposed to go one step further, achieving even more savings by allowing IT to automate processes further as well as farm out key parts of their infrastructure to 3rd parties that can achieve greater economies of scale and thus achieve even more savings.

For customers, since the step to cloud is evolutionary from their regular virtualization infrastructure, they can experiment with small projects to build confidence and test the water. This is already happening today.

A striking example was provided at the event. It involved a company that wanted a new backup redundancy system to their SAP system and compared building a new one internally to hosting one externally using cloud services. They had clearly defined goals of how much data they can lose in case of failure (less than 1 hour) and how quickly the backup system needs to be up (within 20 minutes).

Backup thus had to constantly replicate data from their systems and their servers had to be replicated at the remote hosted site. They ended up choosing the cloud implementation due to significant costs savings, but also gained additional benefits of their disaster recovery with at a remote site and savings in renewing their hardware every few years.

To me, this is a great example of small steps customers can take to test the water. It also highlighted the future is not about private cloud or public cloud but a mesh comprised of private resources where control is critical, and public resources, where possible, that can improve the internal infrastructure on many aspects and introduce additional costs savings not possible internally.

Virtual trade shows, online meetings, con calls, skype - whatever the format, nothing beats face time to make an impression and close a deal. I often forget how important it is at a trade show for people to "see" your corporate brand, team and technology at its best.

My Interop post-mortem report was that it was well worth the investment. The show was buzzing with activity - our booth held non-stop meetings for the first two days of the show (I do, however, question whether there should be a 3rd day of a trade show?). Our panel discussions and booth meetings with potential customers, press and analysts were so colorful in person.

I recently did a lunch & learn event in Boston last week and so enjoyed meeting the people we have been interacting with via phone and email. Again, until you sit down next to someone, it's often hard to gain his or her trust.

Electronic marketing certainly helps the budget, but perhaps we are getting too impersonal for successful business practice?

2 weeks ago I was at the Interop show in Las Vegas. The amazing conclusion from the show is that the networking world is about to be disrupted. I am still surprised by this conclusion mostly due to the fact that in the last few years, networking seems to have settled down to a steady state where things work reasonably well, people are comfortable running their networks and networks pretty much do what we expect them to do.

So why am I jumping to this conclusion? Let me explain.

The innovation pace in networking seems to have slowed in the last few years. The constant stream of new competing technologies that were part of the 90s and early 2000s has somewhat subsided. Ethernet and packet switching has overcome most technologies both in the internal networking world as well as on the WAN (remember ATM ?), it has dominated WiFi standards, and other (non-Ethernet) edge networking technologies like Bluetooth have become mainstream. Even in the datacenter, Ethernet seems to be poised to replace other fast connection technologies such as Fiber Channel.

The latest developments seem to be more incrementally driven then disruptive. Higher speeds of the same basic technology are introduced, improved reception technologies are added (802.11n standard of WiFI), and so forth. All of these developments are usually backwards compatible so rip-and-replace are not as common and deployments have become more gradual.

This year's show was abuzz with interesting announcements and initiatives. All of them were focused on Cloud Computing integrations, although no one seems to know how it will play out. Naturally, most of the talk around Cloud Computing revolved around the application layer, since the application people are the ones pushing Cloud. When confronted with the question of what it would mean for the network, they are at first astonished by the mere question and then react saying they don't really know but feel it will be an critical part to solve.

Let's look at what this means:

The premise of Cloud Computing is of providing flexible computing power which can be turned on or off according to needs and be able to flexibly run any type of workload. To work, it would require the network to respond and adapt on the fly to these changing needs. Such networks would have to play second fiddle to the applications which will mandate the needs. If it is to work at all, new networks would have to be simplified and highly automated, so things would just work when needed. Automation by definition will reduce the amount of work on the side of the networking people, creating friction between the networking groups and application groups. At the end of the day it changes the work of networking and will reduce the amount of people needed to run them.

On the networking vendor side, there are going to be fortunes created and lost based on who can address these Cloud issues better. Since we know it will be done but do not know what the exact winning formula will be, discovery will be based on trials and errors. It is thus not clear who the winners will be.

So stay tuned, we are heading into very interesting times in the network world. Times that will change the networking world as we know it...

Site response time is key to the revenue success of any online company - and it continues to be an area for improvement and optimization.

Crescendo and Alexa have recently teamed up to offer realtime data to show exactly how your site is performing. You can run Crescendo's new performance calculator tool for realtime data or visit http://www.alexa.com/siteinfo to learn how your site compares to to other sites in terms of daily average response time.

Crescendo Networks' AppBeat architecture is the first and only application delivery solution that accelerates, optimizes and controls application performance from the Web front end down to the application transaction level.

Alexa has been crawling the Web since early 1996 and currently gathers approximately 1.6 Terabytes (1600 gigabytes) of Web content per day. This free content site helps IT administrators better understand their web site traffic load and site response times.

Need help understanding how an Application Delivery Controller (ADC) can optimize your site? Contact us today for a free performance consultation.