performance

The Order of (Network) Operations Thought those math rules you learned in 6thgrade were useless? Think again…some are more applicable to the architecture of your data center than you might think. Remember back when you were in the 6th grade, learning about the order of operations in math class? You might recall that you learned that the order in which mathematical operators were applied can have a significant impact on the result. That’s why we learned there’s an order of operations – a set of rules – that we need to follow in order to ensure that we always get the correct answer when performing... posted @ Tuesday, March 09, 2010 3:41 AM | Feedback (0)

Lots of Little Virtual Web Applications Scale Out Better than Scaling Up Surprised? I was, but I shouldn’t have been. While working on other topics I ran across an interesting slide in a presentation given by Microsoft at TechEd Europe 2009 on virtualization and Exchange. Specifically the presenter called out the average 12% overhead incurred from the hypervisor on systems in internal testing. Intuitively it seems obvious that a hypervisor will incur overhead; it is, after all, an application that is executing and thus requires CPU, I/O, and RAM to perform its tasks. That led to me to wonder if there was more data on the overhead from other... posted @ Thursday, February 18, 2010 3:47 AM | Feedback (2)

Scaling AJAX Applications is More About Architecture than Apache Scaling applications that include AJAX and non-AJAX components may require more than just tuning your web server  A common problem after deploying a Web 2.0 AJAX-based application shows itself through poor performance or lower capacity on the server, often both. Web serving tuning is almost always the first step in improving performance and capacity, but the inherently competing behavior of AJAX-requests and “normal” HTTP requests quickly becomes problematic as well. Tune for the AJAX requests and performance of regular old HTTP requests suffers. Tune for regular old HTTP requests, and performance of AJAX-requests suffer. This is... posted @ Monday, February 08, 2010 4:35 AM | Feedback (0)

WILS: SSL TPS versus HTTP TPS over SSL The difference between these two performance metrics is significant so be sure you know which one you’re measuring, and which one you wanted to be measuring.  It may be the case that you’ve decided that SSL is, in fact, a good idea for securing data in transit. Excellent. Now you’re trying to figure out how to implement support and you’re testing solutions or perhaps trying to peruse reports someone else generated from testing. Excellent. I’m a huge testing fan and it really is one of the best ways to size a solution specifically for your... posted @ Wednesday, February 03, 2010 4:10 AM | Feedback (3)

WILS: How can a load balancer keep a single server site available? Most people don’t start thinking they need a “load balancer” until they need a second server. But even if you’ve only got one server a “load balancer” can help with availability, with performance, and make the transition later on to a multiple server site a whole lot easier. Before we reveal the secret sauce, let me first say that if you have only one server and the application crashes or the network stack flakes out, you’re out of luck. There are a lot of things load balancers/application delivery controllers can do with only one server, but automagically fixing... posted @ Wednesday, January 20, 2010 5:58 AM | Feedback (3)

It’s 2am: Do You Know What Algorithm Your Load Balancer is Using? The wrong load balancing algorithm can be detrimental to the performance and scalability of your web applications. When you’re mixing and matching virtual or physical servers you need to take care with how you configure your Load balancer – and that includes cloud-based load balancing services. Load balancers do not at this time, unsurprisingly, magically choose the right algorithm for distributing requests for a given environment. One of the nice things about a load balancing solution that comes replete with application-specific templates is that all the work required to determine the optimal configuration for the load balancer and... posted @ Tuesday, January 05, 2010 3:50 AM | Feedback (3)

The Cloud Computing – Application Acceleration Connection Like peanut-butter and jelly, cloud computing and application acceleration are just better together. Ann Bednarz of Network World waxes predictive regarding 2010 trends in application delivery and WAN optimization in WAN optimization in 2010. One of the interesting tidbits she offers from research firm Gartner is growth in the application acceleration market:  Second, the research firm is predicting a return to modest growth for the application acceleration market in 2010. Gartner is forecasting a compound annual growth rate of 12.22%, with 2014 revenue of $4.27 billion. This, when viewed alongside... posted @ Thursday, December 17, 2009 3:21 AM | Feedback (2)

WILS: Why Does Load Balancing Improve Application Performance? IMAGE CREDIT: DANIEL PENNEY Everyone has surely experienced the frustration of an overloaded desktop/laptop. You’ve just got too many apps open at one time and the performance of your machine has been slowly degrading to the point where you can select an application from the toolbar, run down to the local Starbucks, stop and chat with a friend, and return to find the application still not ready for use. The same thing happens on servers. Even though a web/application server is likely only running a few critical applications,... posted @ Thursday, October 22, 2009 4:13 AM | Feedback (2)

Long Live(d) AJAX The problem of AJAX, interstitial request patterns, and the effect on the performance and availability of your applications. There are several reasons why applications need to be scaled out but they all come down to essentially addressing the same core problem: resource consumption. In the case of networked applications this often means specifically TCP connection resources. Now most people don’t think of TCP connections as a resource, per se, but every web and application server has an upper limit to the number of TCP connections it can hold open at any given time. In some cases this... posted @ Wednesday, October 07, 2009 3:53 AM | Feedback (4)

You’re Asking the Wrong Question About Virtual Appliances A question I often hear is “Why don’t you just move load balancing/application delivery into a virtual appliance model?” My answer is almost always “That’s the wrong question.” The question that should be asked is “What are the potential impacts to the infrastructure and application?” Because the whole point of deploying an application delivery solution – virtual appliance or hardware – is about improving some facet of the infrastructure in order to better deliver your applications. So in order to determine whether using a virtual appliance is a good idea or not you have to ask what the impacts might... posted @ Tuesday, October 06, 2009 3:43 AM | Feedback (9)

Your Network is Not My Network Back in the day when I was actually allowed to write code for customers the pat answer to any code being returned from QA because of problems was a flat “but it works on my machine.” Alright, alright, I’ll be honest; it wasn’t flat at all, it usually a plaintive whine. This isn’t an uncommon scenario as differences in environments and interactions with other applications may be enough to cause problems on one machine and not another. Troubleshooting such subtle issues were painful, to say the least, and not something anyone wanted to do. Now comes the time... posted @ Thursday, September 24, 2009 3:37 AM | Feedback (0)

IT Myths and Legends: Sharing Servers Sharing is core to a successful cloud implementation but not something every organization does well. How do you encourage business stakeholders to play well with others? In most definitions of “cloud computing” there lies a central, key component: shared resources. It is the sharing of resources, in fact, through which many of the benefits of reduced operating expenses are supposed to be achieved. It is the sharing of resources – or perceived inability to share resources – that confounds some folks when discussing private cloud, although there are several ways in which sharing of resources can... posted @ Friday, September 11, 2009 4:01 AM | Feedback (6)

Impact of Load Balancing on SOAPy and RESTful Applications A load balancing algorithm can make or break your application’s performance and availability It is a (wrong) belief that “users” of cloud computing and before that “users” of corporate data center infrastructure didn’t need to understand any of that infrastructure. Caution: proceed with infrastructure ignorance at the (very real) risk of your application’s performance and availability. Think I’m kidding? Stefan’s SOA & Enterprise Architecture Blog has a detailed and very explanatory post on Load Balancing Strategies for SOA Infrastructures that may change your  mind.  This post grew, apparently, out of some (perceived) bad behavior on... posted @ Tuesday, September 08, 2009 4:11 AM | Feedback (1)

WILS: Application Acceleration versus Optimization Why do application delivery vendors talk about both? Aren’t they the same thing? In general, acceleration implies that something will be done to the application: caching, compression, etc… The actual behavior of the application is changed such that the client may need to participate in the acceleration. Acceleration is technically speaking disruptive in the sense that it requires participation of client, intermediary, and often the server. This generally takes a form that leverages existing standards, a la caching, such that no changes need be made to clients or servers, but the behavior of the application and its... posted @ Thursday, August 20, 2009 6:00 AM | Feedback (2)

The Myth of 100% IT Efficiency Idle resources will always need to exist, especially in a cloud architecture With IT focused on efficiency – for reduction in operating expenses and in the interests of creating a greener computing center – there’s a danger that we’ll attempt to achieve 100% efficiency. You know, the data center in which no compute resources are wasted; all are applied toward performing some task – whether administrative, revenue generating, development cycles, or business-related – and no machine is allowed to sit around idle. Because, after all, idleness is the devil’s playground, isn’t it?  But before... posted @ Wednesday, August 19, 2009 3:17 AM | Feedback (3)

Dear Developer: Step Away from the Keyboard When it comes to availability, coding a solution is just delaying the inevitable Jonathan Howell, in Five Things That Will Kill Your Site – an excellent read, by the way, for all web application developers – asserts that there are several ways to avoid web application death that do not require the implementation of “expensive redundant hardware with top of the line load balancers and an enterprise class SAN.” In general he’s got some good advice to which application developers should pay attention, but I had to disagree with his assertion that a solution to provide graceful degradation... posted @ Tuesday, August 11, 2009 3:56 AM | Feedback (0)

A Formula for Quantifying Productivity of Web Applications Ever wanted to prove or understand how the network impacts productivity? There is a formula for that… We often talk in abstract terms about the affects of application performance on productivity. It seems to make sense that if an application is performing poorly – or unavailable – that it will certainly affect the productivity of those who rely upon that application. But it’s hard enough to justify the investment in application acceleration or optimization without being able to demonstrate a real impact on the organization. And right now justification is more of an issue than it’s ever been.  ... posted @ Tuesday, August 04, 2009 4:15 AM | Feedback (1)

To Boldly Go Where No Production Application Has Gone Before The importance of stress-testing in production Everyone is still a-twitter over the problems the web experienced last week right after the news of Michael Jackson’s death. There have been numerous stories on the fact that the Internet nearly fell over itself and died under the strain of trying to support the rush of millions of users as they queried, clicked, watched video, read blogs and news reports on the subject. The Internet itself, of course, was just fine. The infrastructure comprising our electronic highway was humming along, routing packets happily here and... posted @ Wednesday, July 01, 2009 4:14 AM | Feedback (1)

What is server offload and why do I need it? One of the tasks of an enterprise architect is to design a framework atop which developers can implement and deploy applications consistently and easily. The consistency is important for internal business continuity and reuse; common objects, operations, and processes can be reused across applications to make development and integration with other applications and systems easier. Architects also often decide where functionality resides and design the base application infrastructure framework. Application server, identity management, messaging, and integration are all often a part of such architecture designs. Rarely does the architect concern him/herself with the network infrastructure, as that is... posted @ Wednesday, June 17, 2009 4:07 AM | Feedback (4)

The network ain’t big enough for the both of us There is a tendency to describe every device on a network as simply “the network” regardless of whether that device is dedicated to security, or application delivery (layer 4-7), or actual network (layer 2-3) functionality. It’s an artifact of aging data center architecture models that there exists an artificial line of demarcation between web and application servers and everything else. We used to depict “everything else” as a cloud, but with the emergence of The Cloud doing so simply complicates discussions even further because the “network” necessary to support a dynamic, on-demand operational model of computing like “cloud” is more... posted @ Friday, May 29, 2009 3:49 AM | Feedback (9)

Greedy (IT) Algorithms Greedy algorithms can result in the right solution in the end, but rarely do Don and I were having a discussion with our oldest son the other night about writing a chess program. There are myriad options for implementing the learning aspects of a chess program, but this is not a task for the timid. He ended up proposing a much simpler solution (this was just an exercise in ‘can I write it’, after all) that would have essentially used a very greedy algorithm; one that made a decision regarding the computer’s next move based on current state of... posted @ Monday, May 18, 2009 3:16 AM | Feedback (0)

Cloud computing is not Burger King. You can’t have it your way. Yet. Don’t confuse computing services with infrastructure services. We aren’t there yet. The subtext to the cloud computing discussion is subtle, as is the wont of subtext. But it is clear that underlying all the concerns about cloud computing is a common theme: control. Whether we’re talking about reliability or security, it should be obvious if you’re reading between and beneath the lines that the biggest stumbling block to massive cloud adoption is the issue of control. There is a very real difference between on-demand computing and on-demand infrastructure. What the cloud provides now, and is described... posted @ Thursday, May 07, 2009 3:11 AM | Feedback (4)

Dear Slashdot: You get what you pay for Open Source SSL Accelerator solution not as cost effective or well-performing as you think o3 Magazine has a write up on building an SSL accelerator out of Open Source components. It’s a compelling piece, to be sure, that was picked up by Slashdot and discussed extensively. If o3 had stuck to its original goal – building an SSL accelerator on the cheap – it might have had better luck making its arguments. But it wanted to compare an Open Source solution to a commercial solution. That makes sense, the author was trying to show value in... posted @ Friday, April 17, 2009 4:56 AM | Feedback (40)

Why not network-side pre-fetching? The acceleration technique known as pre-fetching went the way of the do-do bird sometime around 2002. But perhaps it should be resurrected, just in a different place and with a slightly different focus. A SHORT HISTORY OF ACCELERATION TECHNIQUES Most modern acceleration techniques revolve around two things: decreasing the amount of data to be transferred (compression, optimization of the client-side cache) or twiddling with protocols (TCP, HTTP) and their associated behaviors to improve the overall speed at which a client and server communicate. Back in the early days of application acceleration most technologies were... posted @ Tuesday, April 14, 2009 3:01 AM | Feedback (0)

Architects Need to Better Leverage Virtualization Leveraging virtualization as a means to create a specialized architecture can realize significant gains in performance and IT efficiency With all the talk about “packaging up applications” in a virtual machine and shipping them off to the cloud, it almost sounds as if virtualization might lead us to a return to architecting monolithic applications. The idea of packaging up everything you need to run an application in a virtual container and relieving the worries about connectors and adapters and integration is certainly appealing. But let’s take a step back from the virtualization craze as it relates to... posted @ Thursday, April 09, 2009 3:34 AM | Feedback (4)

HTTP Pipelining: A security risk without real performance benefits Everyone wants web sites and applications to load faster, and there’s no shortage of folks out there looking for ways to do just that. But all that glitters is not gold, and not all acceleration techniques actually do all that much to accelerate the delivery of web sites and applications. Worse, some actual incur risk in the form of leaving servers open to exploitation. A BRIEF HISTORY Back in the day when HTTP was still evolving, someone came up with the concept of persistent connections. See, in ancient times – when administrators still wore togas in... posted @ Thursday, April 02, 2009 3:30 AM | Feedback (10)

Would you risk $31,000 for milliseconds of application response time? Keep in mind that the time it takes a human being to blink is an average of 300 – 400 milliseconds. I just got back from Houston where I helped present on F5’s integration with web application security vendor White Hat, a.k.a. virtual patching. As almost always happens whenever anyone mentions the term web application firewall the question of performance degradation was raised. To be precise: How much will a web application firewall degrade performance? Not will it, but how much will it, degrade performance. My question back to those of you with the same... posted @ Monday, March 30, 2009 3:21 AM | Feedback (2)

Can the Cloud survive regulation? One of the greatest strengths of the Cloud is that, like the Internet, it knows no boundaries. It crosses industry and international boundaries as if they do not exist. But as is often the case, your greatest strength can also be your greatest weakness. Take Google, for example, and it’s myriad Cloud-based application offerings. A new complaint made by Epic (Electronic Privacy Information Center) to the US Federal Trade Commission urges the regulatory agency to “consider shutting down Google’s services until it establishes safeguards for protecting confidential information.”  From a recent FT.com article: ... posted @ Thursday, March 26, 2009 5:47 AM | Feedback (0)

Remember when…it was sprawl or nothing? Ah, those were the days, weren’t they? When improving the security, reliability, and performance of applications over the LAN, over the WAN, and over the Internet meant you had to deploy many different solutions, each one standing on their own in the data center. When you had to learn how to configure and manage as many devices as you have fingers just to deliver a single business-critical application to users and customers across a wide variety of environments. When there really wasn’t an option because solutions weren’t unified, weren’t contextually aware, and were basically just a bunch of point solutions... posted @ Monday, March 23, 2009 3:21 AM | Feedback (0)

Load Testing as a Service: A Look at Load Impact (beta) I admit it. I’m a load / performance testing junkie. During my years with Network Computing I burned through any number of solutions designed to throw more traffic at products than money Congress is throwing at failed banks these days. And I do mean burned, as the last time I was in the lab there were no less than three non-functioning Spirent Avalanche systems that had given up the ghost after being forced to their absolute limits over years of use and abuse. When I received a note telling me about LoadImpact.com, a load testing as a service site, naturally... posted @ Friday, March 20, 2009 3:21 AM | Feedback (2)

Remember when…you had to choose between security and speed? Ah, those were the days, weren’t they? When you needed a way to add security at several layers to your network and application network infrastructure but knew that implementing a solution capable of securing those pesky applications was more than likely going to end up with poor performance and angry users. When you needed to add something to secure applications and the network against the growing wave of attacks but knew that doing so would negatively impact performance. It was a tough choice, and most people ended up going the route of maintaining application performance at the expense... posted @ Monday, March 16, 2009 3:39 AM | Feedback (0)

Remember when…you had to choose between agility and performance? Ah, those were the days, weren’t they? When you needed a way to inspect data at the edge for application-specific issues but knew that implementing a solution capable of that kind of agility was more than likely going to end up with poor performance and angry users. When you needed to add something to secure applications and the network against the growing wave of attacks but knew that doing so would negatively impact performance. It was a tough choice, and most people ended up going the route of maintaining application performance at the expense of security and optimization... posted @ Monday, March 09, 2009 4:30 AM | Feedback (1)

WAN Optimization is not Application Acceleration Increasingly WAN optimization solutions are adopting the application acceleration moniker, implying a focus that just does not exist. WAN optimization solutions are designed to improve the performance of the network, not applications, and while the former does beget improvements of the latter, true application acceleration solutions offer greater opportunity for improving efficiency and end-user experience as well as aiding in consolidation efforts that result in a reduction in operating and capital expenditure costs. WAN Optimization solutions are, as their title implies, focused on the WAN; on the network. It is their task to improve the utilization of bandwidth,... posted @ Wednesday, March 04, 2009 3:29 AM | Feedback (0)

The Great Client-Server Architecture Myth The webification of applications over the years has led to the belief that client-server as an architecture is dying. But very few beliefs about architecture have been further from the truth. The belief that client-server was dying - or at least falling out of favor -  was primarily due to fact that early browser technology was used only as a presentation mechanism. The browser did not execute application logic, did not participate in application logic, and acted more or less like a television: smart enough to know how to display data but not smart enough to do anything... posted @ Monday, February 02, 2009 4:38 AM | Feedback (3)

What's good for the network is not always good for applications Just because you can, doesn't mean you should. I'm going to start this one by quoting Hoff who was quoting Andreas Antonopoulos of Nemertes Research Group who was paraphrasing a concept put forth by Doug Gourlay. From Rational Survivability "How about using netflow information to re-balance servers in a data center" Routing: Controlling the flow of network traffic to an optimal path between two nodes Virtual-Routing or Anti-Routing: VMotioning nodes (servers) to optimize the flow of traffic on the network. Using netflow information, identify those... posted @ Wednesday, December 17, 2008 4:03 AM | Feedback (0)

9 ways to use network-side scripting to architect faster, scalable, more secure applications You may recall a recent overview on network-side scripting that described a few uses of this technology integrated with application delivery controllers. With thousands of examples of the uses of network-side scripting it's hard to choose just one to adequately represent its potential. Luckily, we don't have to stick to just one. Viva la Internet! Based on the technical session the great network-side scripting guru Colin and I ran at SD Best Practices in October, I've pulled nine ways to use network-side scripting that can enhance the scalability, security, and performance of web applications into a presentation for... posted @ Thursday, December 11, 2008 4:04 AM | Feedback (4)

Cloud Computing: Vertical Scalability is Still Your Problem Horizontal scalability achieved through the implementation of a load balancing solution is easy. It's vertical scalability that's always been and remains difficult to achieve, and it's even more important in a cloud computing or virtualized environment because now it can hurt you where it counts: the bottom line. Horizontal scalability is the ability of an application to be scaled up to meet demand through replication and the distribution of requests across a pool or farm of servers. It's the traditional load balanced model, and it's an integral component of cloud computing environments. Vertical scalability is the ability of... posted @ Tuesday, November 25, 2008 3:29 AM | Feedback (5)

A client is still a client even when it's on the space station While I was at SD Best Practices in Boston last month I got to talk to a lot of engineers, developers, and architects about their environments and about what F5 does for application delivery. One of the developers glibly told me he wasn't sure we could help him out because his environment was the international space station. Yeah, how cool is that? Now that's cloud computing. Another architect, who turned out to be a friend of a friend who I've conversed with but never met in person said the same thing, but... posted @ Friday, November 14, 2008 3:08 AM | Feedback (0)

Amazing Application Acceleration: Simultaneously improve productivity, efficiency, and performance As a general rule, we spend far more time worrying about external appearances than we do internal. We are more concerned with our external web applications and how they look - and perform - than we are likely to regarding our intranet or internal only applications. This blog post was interesting in that rather than encouraging folks to optimize web sites and improve end-user response time for web applications for the sake of the user experience, it focused on the relationship between page load time and impact on Google AdWords quality scores. Which is a bit different than... posted @ Thursday, November 13, 2008 3:36 AM | Feedback (0)

The ironic truth about the ugly truth about web application acceleration Lately I've been seeing quite a few links to a white paper popping up in my alerts and feed-reader. Regardless of who's linking to it, it generally reads as promising to reveal some grand secret about how web application acceleration is an epic failure. I finally gave in and clicked on a link and ended up directed to download a white-paper, the description for which essentially distilled "web application acceleration" down to "caching". And then promised to tell me why caching wasn't a good way to accelerate web applications. I didn't download the white paper primarily because equating... posted @ Friday, October 10, 2008 3:17 AM | Feedback (0)

Moore's law is a double-edged sword In the good old days when I was in college I had a generic PC. That's the way we did it back then - we built our PCs out  of parts (obligatory "you kids don't know how good you have it these days" look). On that PC is something you don't often see today; a small toggle switch that changed the processor clock rate from 4 to 7 MHz. That's right, I said MHz. Not GHz.  That was not that long ago in real years, but in technological years it's been a lifetime. As Moore's law correctly predicts,... posted @ Tuesday, October 07, 2008 4:10 AM | Feedback (0)

The impact of the network on ... everything Back in the day when I was a technical architect and actually wrote code (yes, they did let me do that once) I got into a discussion with the rest of my team about the impact of our code on performance. I was saying white-space was evil because it can unnecessarily increase the number of packets necessary to transfer data. I wanted to go through the code (mostly JavaScript and HTML output) and reduce the white-space to make application... posted @ Thursday, September 11, 2008 8:01 AM | Feedback (1)

The third greatest (useful) hack in the history of the Web Developers have an almost supernatural ability to workaround restrictions, even though some of the restrictions on building applications delivered via the web have been akin to a kryptonite. Like Superman fighting through the debilitating effects of the imaginary mineral, they've gotten around those restrictions by coming up with ways to implement functionality and improve the behavior of browsers and thus web applications anyway. The first greatest hack was giving HTTP state. The second? Cookie-based persistence. The third? The CNAME trick. THE PROBLEM The reason the "CNAME trick" came about was a limitation on browser connections... posted @ Monday, September 08, 2008 4:13 AM | Feedback (1)

IE8: Robbing Peter to pay Paul For those of you unfamiliar with the idiom, it should be taken to mean "benefiting one at the expense of another." In this case, Paul is the end-user and Peter is the server administrator. Or better yet, Paul is the browser and Peter is the server. All web browsers, including IE (Internet Explorer), impose a per-server connection limit was imposed to reduce overload on servers. This was introduced back when the web was exploding and browsers opened up connections willy-nilly and made server operators cry. Often. The limitation imposed by IE (two connections per host) was harsher... posted @ Friday, September 05, 2008 4:19 AM | Feedback (5)

Packets, shmackets. What about the apps? As I was reading the Internet this morning I happened across an article with "Tips for Optimizing Your WAN (Wide Area Network)" and I thought, "Huh. That's pretty ... generic."   While the article uses SAP applications as an example, it speaks in terms of generalities. Selective ACKs, quality of service, data reduction techniques, and HTTP compression. That's when I said, "Whoop de doo." Really, these techniques have nothing to do with SAP and applications and everything to do with packets. Every WAN and acceleration solution can do this stuff. I'm not really picking... posted @ Wednesday, August 27, 2008 5:14 AM | Feedback (1)

How Coding Standards Can Impair Application Performance One of the "real world" lessons rarely taught in the university setting is that in the "real world" you're going to have to follow coding standards. Back in the day, when I was allowed to code, I often railed against some of those coding standards on the basis that they impaired application performance. Anyone with a firm grounding in computer science knows that the introduction of a local scope necessarily means more work (and thus memory and cycles consumed) to set up the stack: copying variables, pushing parameters, etc... That means that a conditional statement with just one... posted @ Tuesday, August 19, 2008 5:29 AM | Feedback (6)

Reliability does not come from SOA Governance An interesting InformationWeek article asks whether SOA intermediaries such as "enterprise service bus, design-time governance, runtime management, and XML security gateways" are required for an effective SOA. It further posits that SOA governance is a must for any successful SOA initiative. As usual, the report (offered free courtesy of IBM), focuses on SOA infrastructure that while certainly fitting into the categories of SOA intermediary and governance does very little to assure stability and reliability of those rich Internet applications and composite mashups being built atop the corporate SOA. Effective SOA Requires Intermediaries via InformationWeek ... posted @ Monday, August 18, 2008 5:00 AM | Feedback (1)

The Unpossible Task of Eliminating Risk An ant named Archimedes is in a hole 6' deep. He climbs half the distance to the top every hour. How long does it take for him to escape the hole? Trick question. He can never, mathematically, escape. Realistically, we know that when Archimedes gets close to the top he will escape because he is actually longer than the amount of hole he has left to go. But what if every hour that Archimedes climbed the hole expanded 6" and thus changed the equation? He'd be one frustrated ant, that's what he'd be. That's how... posted @ Monday, August 11, 2008 3:54 AM | Feedback (4)

8 things you can do with an ADC to make your apps secure, fast, and available An application delivery controller (ADC) essentially acts a reverse proxy. That means that client requests interact with the ADC, and the ADC interacts with web and application servers on the client's behalf. This mediation offers the chance to implement acceleration, availability, and security features without requiring changes to existing applications. There are many, many more features in an ADC that provide significant value. These eight capabilities are the most commonly employed features in reverse-proxy application delivery solutions that provide immediate benefits to web applications, and all can be used without modifying applications or the servers on... posted @ Friday, August 01, 2008 4:56 AM | Feedback (2)

Architecting for Speed               I'm going to give you an engine low to the ground.               An extra-big oil pan that'll cut the wind underneath you.               That'll give you more horsepower.               I'll give you a fuel line that'll hold an extra gallon of gas.               I'll shave half an inch off you and shape you like a bullet.               When I get you primed, painted and weighed... ... posted @ Friday, July 25, 2008 11:30 AM | Feedback (0)

4 Things You Need in a Cloud Computing Infrastructure Cloud computing is, at its core, about delivering applications or services in an on-demand environment. Cloud computing providers will need to support hundreds of thousands of users and applications/services and ensure that they are fast, secure, and available. In order to accomplish this goal, they'll need to build a dynamic, intelligent infrastructure with four core properties in mind: transparency, scalability, monitoring/management, and security.  Transparency One of the premises of Cloud Computing is that services are delivered transparently regardless of the physical implementation within the "cloud". Transparency is one of the foundational concepts of cloud computing, in that the actual implementation of... posted @ Thursday, July 10, 2008 5:45 AM | Feedback (4)

Performance Testing Web 2.0: Don't forget the APIs Keynote, well known for its application performance testing and monitoring services, just announced a new version of its KITE (Keynote Internet Testing Environment) that is now capable of testing Web 2.0 sites that make use of AJAX, Flash, and other "hidden" methods of obtaining content. Announcement of KITE 2 Performance testing dynamic and HTML websites is now a fairly straightforward process, however the rise of Web 2.0 sites that don’t rely on clicking to reveal another new page have been almost impossible to test. However Keynote has now developed a scripted system that allows you to... posted @ Wednesday, July 09, 2008 5:06 AM | Feedback (0)

Web 2.0: Integration, APIs, and Scalability Web 2.0 is built on primarily two technologies: AJAX and RSS. AJAX is used to develop interactive, real-time applications while RSS is primarily used as for integration and syndication. Import a feed, share a feed, drag-n-drop a gadget, widget, or component. It's all RSS (XML) today. It's further becoming a requirement of Web 2.0 sites that they provide some sort of API through which developers can write add-on applications. Twitter, Tumblr, Facebook. They all offer APIs that are quite heavily used at this time and startups are following suit. Other sites offer richer media, like video or slideware,... posted @ Tuesday, July 01, 2008 4:53 AM | Feedback (1)

Application Acceleration 2.0 : Breaking Browser Limitations Several years ago it became necessary for browsers to put limitations on the number of simultaneous connections allowed not only to be open, but how many of those could be open to a single domain. This helped prevent unintentional (and, in some cases, intentional) denial of service situations where a site's poor web server just couldn't keep up with the demand. After all, managing TCP/IP connections is expensive and if one user hogs all the available connections (as determined by web server configuration and RAM) there may be hundreds of users out there that are denied access to the latest... posted @ Tuesday, June 17, 2008 8:00 AM | Feedback (0)

Composing SOA: Music to your ears With apologies to the writers of Amadeus MOZART [The fresh SOA Architect] But it's new, it's entirely new. It's so new, people will go mad for it. For example, I have an activity in the second step - it requires calls to two services in parallel. Then a third service is called to verify the name of the customer, and a fourth to perform some security checks. Then a logging service makes five and so on. On and on, six, seven, eight! How long do you think I can sustain that? ... posted @ Thursday, May 08, 2008 10:56 AM | Feedback (2)

Green IT: You don't have to sacrifice speed The Green Tech Blog on CNET News postulates that the next green trend will be to s l o w down the innertubes, or more accurately, the flow of data. Now that slow down is apparently measured in terms of milliseconds, and is "not enough for Web surfers to notice" according to researchers. But as we recently discussed, milliseconds at every hop can potentially add up to seconds, and seconds will certainly be noticeable by Web surfers - particularly those who might be engaged in sensitive financial transactions like selling and buying stocks. And we won't even discuss the... posted @ Wednesday, May 07, 2008 11:04 AM | Feedback (0)

Imagine...Manageability We don't often consider the impact of manageability of technology in our daily lives, even though it's become an integral part of just about every aspect of our lives. Likely most prevalent amongst technology management issues is how we deal with our home entertainment systems. From a desire to manage all the devices that deliver and control various forms of media - cable, DVDs, games, etc... - with a single, intelligent mangement device evolved what we like to call the "universal remote". These little management devices are able to control every component comprising our home entertainment system, greatly reducing the cost... posted @ Wednesday, January 09, 2008 2:31 PM | Feedback (0)

Imagine...Performance Every industry measures performance, we just use different jargon to discuss it. When we talk about the raw power of a car engine we talk in terms of horsepower; of harnessing the performance of hundreds of horses such that they work together as a single unit. In the world of computing we use terms like MIPS (million instructions per second), and in the world of application delivery we measure performance in terms of transactions per second (TPS). The problem in the world of computing is, unfortunately, that simply adding more "horses" to the mix doesn't linearly increase performance. Generally... posted @ Wednesday, January 02, 2008 2:12 PM | Feedback (0)

Jack of all trades, master of none Alan Shimel applauded a recent blog post by Eric Ogren regarding the "Advances by Intel and AMD in compute power with multi-processors and management with virtualization" claiming that these advances "have shifted the game for security vendors who are bringing their products to market as a high performance appliance." Nevis Networks posted a rebuttal, and the comments responding to Eric's post were generally of the same bent: ASICs are not likely to be replaced by general purpose (commodity) processors, regardless of their capabilities. While this current debate is focused on the security market and security-specific ASICs, this isn't a new... posted @ Tuesday, November 27, 2007 2:23 PM | Feedback (4)

All your performance are belong to us The evolution of programming languages and environments and the impact on performance Chances are that if I ask my son, a third-year computer science major, about Big(O) I'll either get that look - the one that says he's had that discussion with his father years ago and he really doesn't want to discuss such things with his mother - or he'll dismiss it as not relevant to today's computing environment. Big(O) and algorithmic performance is just not that important to today's generation of developers who are too often being taught to code within a vaccuum, or to be more accurate,... posted @ Tuesday, October 02, 2007 9:23 AM | Feedback (1)

Performance vs Reliability Our own Deb Allen posted a great tech tip yesterday on conditional logic using HTTP::retry with iRules. This spawned a rather heated debate between Don and myself on the importance of performance versus reliability and application delivery, specifically with BIG-IP. Performance is certainly one of the reasons for implementing an application delivery network with an application delivery controller like BIG-IP as its foundation. As an application server becomes burdened by increasing requests and concurrent users, it can slow down as it tries to balance connection management with execution of business logic with parsing data with executing queries against a database with making... posted @ Thursday, September 20, 2007 9:35 AM | Feedback (1)

Your Web Services Assignment for the day... Is to head on over to Michael Botis' blog and read this entry on the impact of Web Services on the network. The reason is because Michael is looking at the impact from a global perspective whereas I've primarily concetrated on the affect of services on the local network and infrastructure. Michael points out that BIG-IP Global Traffic Manager (GTM) can assist in ensuring reliable access to servers across geographically disperse locations. Two scenarios come to mind that take advantage of GTM: global failover and distribution of services. The former is a fairly straightforward use-case, the latter is more complex... posted @ Friday, September 14, 2007 10:56 AM | Feedback (0)

The Open Performance Testing Initiative Performance. Everybody wants to know how things perform, whether it be cars, laptops, XML gateways, or application delivery controllers. It's one of the few quantifiable metrics used to compare products when IT goes shopping, especially in the world of networking. Back at Network Computing I did a lot of testing, and a large portion of that testing revolved around performance. How fast, how much data, how many transactions, how many users. If it was possible, I tested the performance of any product that came through our lab in Green Bay. You've not had fun until you've actually melted an SSL... posted @ Monday, September 10, 2007 7:06 AM | Feedback (3)

Performance Impact: Granularity of Services ZapThink has a great article regarding the granularity of services; that is, how fine or coarse grained services are in terms of the services and interactions available. What is mentioned, but not highlighted, and appears to be somewhat assumed (at least in this article), is that the end-result, regardless of the process used to build services, revolves around business processes. [The] concept of granularity is incredibly important to the enterprise architect because it has a direct impact on two major goals of Service-orientation: the composability of loosely-coupled Services, and the reusability of individual Services in different contexts. Before an architect... posted @ Friday, August 03, 2007 11:56 AM | Feedback (0)