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network
There are 41 entries for the tag network
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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 |
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The advent of virtualization brought about awareness of the need to decouple applications from IP addresses. The same holds true on the client side – perhaps even more so than in the data center. I could quote The Prisoner, but that would be so cliché, wouldn’t it? Instead, let me ask a question: just which IP address am I? Am I the one associated with the gateway that proxies for my mobile phone web access? Or am I the one that’s currently assigned to my laptop – the one that will change tomorrow because today I am...
posted @ Thursday, March 04, 2010 3:54 AM |
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Or more apropos, it’s in the complex and intimate relationship between applications and their infrastructure. What’s the difference between a highly virtualized corporate data center and a cloud computing environment? There are probably many, but the most important distinction – and the one that earns the latter a “cloud computing” tag – is certainly that the former lacks a comprehensive orchestration system and was likely not architected using a rapid, infrastructure inclusive, scalability strategy. Mitch Garnaat, “The Elastician”, recently managed to sum up what should be every modern data center’s motto in a...
posted @ Monday, February 15, 2010 4:06 AM |
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Emerging architectures are conflating responsibilities up and down the application stack. Who is responsible for integration when services reside in the network? While preparing for an upcoming panel I’m moderating at Cloud Connect (in the “New Infrastructure” track), the panelists and I had a great discussion on the topics we wanted to discuss in the session. During that discussion it became increasingly clear that an interesting phenomenon has been occurring: the conflation of network and application responsibilities in the traditional “stack.” Much of this inversion is absolutely necessary for emerging models of networking and computing...
posted @ Tuesday, February 02, 2010 3:36 AM |
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Cloud computing can’t assure availability of applications in the face of a physical network outage, can it? Cloud computing providers focus on providing an efficient, scalable environment in which applications can be deployed and provide for their availability with load balancing services and health monitoring and elastic scalability. But it can’t assure availability of your network. The Rackspace outage late last year was allegedly caused by a peering issue. You know, a network, problem. UPDATE: “The issues resulted from a problem with a router used for peering and backbone connectivity located outside...
posted @ Wednesday, January 13, 2010 5:46 AM |
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If you’re just trading “specialized” hardware for “dedicated” hardware you’re losing more than you’re gaining. Apparently I have not gotten the memo detailing why specialized hardware is a Very Bad Thing(TM) . I’ve looked for it, I really have, but I cannot find it anywhere. What I did find was any number of random press releases announcing how “virtual version X” of some network or application infrastructure solution was now virtualized and hey, you don’t specialized hardware to run it. These random press releases neglect, I might add, to mention that there's very little difference between the requirement...
posted @ Monday, January 11, 2010 3:21 AM |
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Are you monitoring the network, servers, stack, or the application? The answer may mean the difference between your application being available or not. One of the biggest problems with moving away from simple load balancing to application delivery is that network teams don’t often get the memo and the application teams don’t have a good understanding of what load balancers can do so they can’t even offer suggestions regarding how to architect a better solution to availability. That means neither team really understands the role of health monitoring in maintaining availability for applications. What should happen...
posted @ Wednesday, September 30, 2009 3:25 AM |
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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 |
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There’s more than one way to address the rapid rate of change in infrastructure supporting a dynamic environment. We spend a lot of time talking about how software and systems and standards are the ultimate solution to addressing the rapid rate of change in the association between applications and IP addresses in a dynamic infrastructure. But sometimes you have look down the stack to find a simpler, more economical and honestly, elegant, answer to the challenge of managing the problem associated with virtualized and cloud computing architectures. We need to take another look at the link layer...
posted @ Friday, September 18, 2009 3:19 AM |
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Are you load balancing servers or applications? Network traffic or application requests? If your strategy to application availability is network-based you might need a change in direction (up the stack). Can you see the application now? Network load balancing is the distribution of traffic...
posted @ Tuesday, September 15, 2009 4:16 AM |
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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 |
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If they can take down Twitter via DNS, they can take your site, too.
Everyone is talking about the DoS (Denial of Service) attack on Twitter but most of them are missing what really happened. We’re so used to defending against HTTP-based DoS attacks that we’ve missed that it’s much easier to DoS a site based on the most critical piece of infrastructure on the Internet: DNS.
If you really wanted to take out a site like Twitter or Facebook using an HTTP-based DoS it would take a whole lot of serious traffic because those sites are designed and architected...
posted @ Thursday, August 06, 2009 2:40 PM |
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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 |
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The concept of a server needs to go the way of the dodo One of the reasons I enjoy Twitter is that quite frequently – if you’re following the right people – you’ll see a tweet that is absolutely profound despite its simplicity and the constraints placed upon the author. Recently we were having a mini-discussion on Twitter regarding the definition of availability that elicited just such a golden nugget from botchagalupe: “Apps designed for a cloud should remove the ‘server’ concept.” First, I really like the use of the article “a” in...
posted @ Friday, July 31, 2009 3:41 AM |
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The importance of a full-proxy architecture to application delivery, security, cloud computing, and virtualization People often describe the act of changing focus from one related but distinct task to another as “wearing two different hats.” Like moving from “developer” to “administrator” when you’re trying to deploy an application in a testing environment. You’re the developer, but then you have to “switch gears” and become a server administrator in order to ensure that the application server and its environment is configured properly before you can actually test the application you just wrote. But the metaphor...
posted @ Thursday, July 30, 2009 4:07 AM |
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I am not a number, I am a free man! – "The Prisoner", sampled by Iron Maiden (edited because geeks are picky and well, they're right even though I always think of Maiden and Eddie first before getting to the actual origins)
We, meaning everyone who deals with technology for a living, know that the move to IPv6 is inevitable. We simply must migrate in order to maintain the scalability of the Internet and its infrastructure. Well, we could continue to use technologies like NAT and SNAT in order to conserve IPv4 addresses, but really that’s just not practical...
posted @ Monday, June 22, 2009 3:54 AM |
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You can’t differentiate until you do something different Gartner analyst and cloud pundit Lydia Leong reminds us that without differentiation, all clouds look pretty much the same. “These are traits that it doesn’t take a genius to think of. Most are known requirements established through a decade and a half of hosting industry experience. If you want to differentiate, you need to get beyond them.” [emphasis added] She lists traits common to most cloud providers: premium equipment, VMWare-based, private VLANs, private connectivity, and co-located dedicated gear but doesn’t really get into...
posted @ Thursday, June 18, 2009 2:40 AM |
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Automating components is easy. It’s automating processes that’s hard. The premise that if you don’t have an infrastructure comprised solely of Infrastructure 2.0 components then you cannot realize an automated, on-demand data center is, in fact, wrong. While the capabilities of modern hardware that come with Infrastructure 2.0 such as a standards-based API able to be leveraged by automation systems certainly makes the task all the more simple, it is not the only way that components can be automated. In fact, “legacy” infrastructure has been automated for years using other mechanisms that can certainly be incorporated into the...
posted @ Monday, June 08, 2009 3:14 AM |
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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 |
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If they aren’t now then Infrastructure 2.0 may force them in that direction - and vice versa. My brother (yes, it does run in the family) has a degree in computer science which, by most definitions, makes him a developer. That’s the focus of most computer science focused degree programs, much to the chagrin of the myriad other IT-focused specialties like networking, security, and operations. Interestingly enough, he worked his way through college as a sysadmin and his first job out of college was as a sysadmin. And now he’s doing a little of...
posted @ Wednesday, May 13, 2009 3:51 AM |
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Brother, can you give a developer a hand? As the topology of networks delivering applications becomes increasingly complex it becomes more and more difficult to troubleshoot problems, especially for developers tasked with figuring out why their “application broke” in production when it was working just fine thank you very much in “DEV” and “QA.” It is rare, after all, that the production environment – including all the moving parts – is duplicated in development and testing environments. It is already difficult enough for developers to track down problems due to the complex nature of application infrastructure...
posted @ Wednesday, May 06, 2009 4:17 AM |
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What is this application delivery thing that everyone keeps telling me I need? Isn’t that just the latest marketing term for load balancing? A recently released Forrester report concludes that “firms must develop and integrated strategy for application delivery.” We don’t disagree with that, or with the Gartner report claiming that “Load Balancing is Dead, Time to Focus on Application Delivery.” Application delivery is the next step in the logical evolutionary path from the tactical solution of load balancing to a comprehensive application infrastructure strategy. Forrester’s research indicates that despite the fact that application...
posted @ Monday, April 20, 2009 3:40 AM |
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This whole Web 2.0-sucking-the-life-out-of-servers problem? Yeah, it’s nothing new if you’ve been paying attention. I am not one prone to fits of smug arrogance. I don’t generally ever say “I told you so” (even if I did) or tsk-tsk when you failed to listen to some nugget of wisdom and it bites you some place…unpleasant. Don often tells me I should, and he will if I won’t, but most of the time I simply bite my tongue and let it pass on by. It’s my job to offer up the information, not force it down your throat....
posted @ Thursday, April 16, 2009 3:46 AM |
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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 |
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Mike Fratto loves to tweak my nose about web application security. He’s been doing it for years, so it’s (d)evolved to a pretty standard set of arguments. But after he tweaked the debate again in a tweet, I got to thinking that part of the problem is the definition of web application security itself. Web application security is almost always about the application (I know, duh! but bear with me) and therefore about the developer and secure coding. Most of the programmatic errors that lead to vulnerabilities and subsequently exploitation can be traced to a lack of secure...
posted @ Wednesday, March 11, 2009 3:21 AM |
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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 |
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According to the definition of cloud computing used by Avanade for a recently released and often cited study on the use of cloud computing, I could claim to be a cloud computing provider. And so could you. Basically, so could just about everyone who happens to run web-based applications accessed over the Internet. From the summary of the report: In the midst of widespread economic turmoil, this global survey of C-level executives and IT decision-makers shows a clear, collective mandate: use technology to cut the cost of doing business. ...
posted @ Tuesday, March 03, 2009 2:59 AM |
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Owning the stack is important to security, but it’s also integral to a lot of other application delivery functions. And in some cases, it’s downright necessary. Hoff rants with his usual finesse in a recent posting with which I could not agree more. Not only does he point out the wrongness of equating SaaS with “The Cloud”, but points out the importance of “owning the stack” to security. Those that have control/ownership over the entire stack naturally have the opportunity for much tighter control over the "security" of their offerings. Why? because they...
posted @ Wednesday, February 25, 2009 3:13 AM |
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While doing some research on a related topic I dug into the technical aspects of Obama's Blueprint For Change. The plans around technology are fairly nebulous, with a few exceptions, such as those related specifically to broadband access: Deploy Next-Generation Broadband: Barack Obama believes we can get broadband to every community in America through a combination of reform of the Universal Service Fund, better use of the nation’s wireless spectrum, promotion of next-generation facilities, technologies and applications, and new tax and loan incentives. On this front, a U.S. House committee recommended yesterday...
posted @ Friday, January 16, 2009 4:08 AM |
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It has been suggested more than once, by folks normally considered rational, that in a cloud computing implementation everything - and I mean everything - should be virtualized. Even the infrastructure. The hype surrounding virtualization has spread not just to applications and their virtual image deployment as a means to achieve dynamic horizontal scale but also to infrastructure, to routers and switches and security devices. Indeed, there are a good number of infrastructure vendors currently offering and others feverishly working on virtual appliance versions of hardware devices for deployment in cloud and virtual computing environments. Part...
posted @ Monday, January 12, 2009 4:29 AM |
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dy·nam·ic (adj) Characterized by continuous change, activity, or progress flex·i·ble (adj) Responsive to change; adaptable. Able to bend without breaking Infrastructure 2.0 is, at its core, about not just the network but the entire infrastructure evolving to a new level of interconnectedness, one in which the underlying infrastructure devices become flexible and adaptable; capable of responding to the continuous change in the next generation data center without breaking. The demands placed upon infrastructure by virtualization, consolidation, and the cloud require that networks grow out of their static configuration models and adopt a more...
posted @ Tuesday, January 06, 2009 6:56 AM |
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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 |
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The diseconomy of scale so adversely affecting the IP address management space isn't limited to network infrastructure; it's crawling up the stack steadily and infecting all layers of the data center like some kind of unstoppable infrastructure management virus. That is why, even with the simple act of managing an enterprise network’s IP addresses, which is critical to the availability and proper functioning of the network, actually goes up as IP addresses are added. As TCP/IP continues to spread and take productivity to new heights, management costs are already escalating. -- Greg Ness, "What Are the Barriers to...
posted @ Monday, November 24, 2008 3:47 AM |
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Michael Vizard over at eWEEK makes an interesting prediction about the future of application acceleration: "Some day the whole concept of application acceleration will be baked into the core routers and switches we have in place." I disagree. Routers and switches are packet-based. They focus on getting a single packet from here to there based on layer 2/3 information. Application acceleration solutions require action higher in the stack, usually layer 4 through 7; they are flow or connection based, and are often specific to the application (think CIFS, SAMBA, HTTP, etc..). The information necessary for application acceleration solutions...
posted @ Tuesday, November 18, 2008 3:38 AM |
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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 |
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Whenever there is a shift in architectural thinking about technology, such as is happening right now with cloud computing and virtualization, we start thinking forward, past the now, and into the future about how that technology might be leveraged. We start looking at the impact to architecture from the top of the stack to the bottom. For a company that's focused on application delivery, that means taking a good hard look at how that new technology might impact the architecture of applications. It's been suggested that perhaps, just maybe, we'll see service-oriented clouds; that the concepts of SOA...
posted @ Wednesday, November 12, 2008 8:52 AM |
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When SOA was the hot topic of the day (not that long ago) everyone was pumped up about the ability finally align IT with the business. Reusability, agility, and risk mitigation were benefits that would enable the business itself to be more agile and react dynamically to the constant maelstrom that is "the market". But only half of IT saw those benefits; the application half. Even though pundits tried to remind folks that the "A" in SOA stood for "architecture", and that it necessarily included more than just applications, still the primary beneficiary of SOA has been applications...
posted @ Monday, November 10, 2008 8:23 AM |
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Many people are concerned with virtualization security (already coined VirtSec), and they're applying that concern from the virtual images all the way down the stack, to the network infrastructure through which virtualized application traffic is delivered. The desire for network infrastructure to be itself virtualized is growing out of a perceived need to isolate application traffic at every point in the infrastructure. But the technology to isolate application traffic at layer 2 and 3 of the infrastructure already exists, and has been essentially virtualized for years.
The sudden desire for everything in the infrastructure to be virtualized completely is borne...
posted @ Friday, November 07, 2008 6:33 AM |
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You have just been promoted to CTO of Widgets, Inc. (Congratulations, by the way!) In your new role, on which of the following will you focus the most attention (and budget): (a) the network (b) the applications (c) the data Trick...
posted @ Thursday, October 23, 2008 4:40 AM |
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Cisco CEO John Chambers recently announced that the slowdown in corporate IT spending will continue until 2009. NEW YORK (Fortune) -- Cisco chief John Chambers has some bad news for the technology sector: He no longer expects the recent slowdown in tech spending to pick up until next year at the earliest. IT is still spending dollars, but not as freely as in past years. In a constrained budgetary environment, IT now has to ask the question, "What's going to give me the best bang for my buck?" ...
posted @ Tuesday, July 15, 2008 5:16 AM |
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Neil McAllister @ InfoWorld has a great blog post on The Web development skills crisis. He postulates at that "The most agile developers, however, are those who approach programming with a firm grounding in computer science."
Amen, brother. Say it again, only this time loud enough my son hears you.
The basic premise of Neil's post revolves around the frenetic rate at which programming technology is changing. It isn't just languages, though that is certainly part of the mix, it's also the increasing number of libraries and frameworks from which web developers can choose to develop web applications.
In order to...
posted @ Monday, July 14, 2008 8:31 AM |
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