|By Sean Rhody||
|March 27, 2003 12:00 AM EST||
Back in the old days, when you needed to communicate with someone distant, you usually had to send a letter. There was no instant response, and there was no way to tell when your message was received. Now we have always-on e-mail, BlackBerrys, and assorted other devices to make what was once a leisurely (or agonizingly slow) process instantaneous, and synchronous.
This issue is about the battle of two idioms - instant, synchronous communication, as championed by the Remote Procedure Call; and asynchronous communication (which may still be instantaneous, but doesn't have to be), represented by the message-based camp.
Web services is about communication, plain and simple. Two (or even more) computers work together to accomplish a task, sometimes directed by human beings, sometimes working based on some program. To work together, the computers exchange information. Web services makes this easy by standardizing the approach to this communication.
But what isn't standardized, at least in theory, is how the communication takes place. That is to say, one approach is the default, but it is not the only allowed, or possible, approach.
By default, a Web service is synchronous. It's simplest to think of it in that sense because an RPC is a very simple concept and the coordination of the interaction is very easy to understand. You simply connect to the service, invoke it, then wait for the response, which you normally would expect instantaneously, or nearly so.
This works well for some things, especially if you expect that the service can provide a quick response. But for other types of applications, particularly ones in which human interaction or workflow might be involved, they are less appropriate. Especially bad is the situation where multiple parties have to be coordinated.
Consider an example where a service might have to arrange for shipping, insurance, bills of lading, even letters of credit. Many parties need to be coordinated here, and not all will be able to respond in a synchronous fashion. In this case, instead of a function call what we really need is to create a conversation.
Of course modeling such a service is inherently more complex. Leaving out the transport mechanisms and callback models for the time being, just drawing a flowchart of such a process might result in pages of lines and boxes, choices and exceptions. And yet, given the nature of the transaction, the complexity is a part of the actual conversation and can't be simplified.
Which brings us back to the reason that Web services doesn't specify how the information needs to be delivered - so that we can define a service, and then define the protocol over which it communicates. We can, for example, use SMTP to move messages over e-mail channels, or use JMS in the Java world to communicate (assuming all the firewalls will cooperate), or use a more generic solution such as Tibco or MQ Series. Other options are possible too.
But with this flexibility comes a bit more complexity as well. With message-based Web services, we have to devote more thought to what exactly a service, or transaction, is, and how we will know when it is over, and whether it succeeds. These issues are not as important in the RPC world because the transaction is (usually) a single synchronous invocation and as soon as we get the response from the remote system we have the answer. Unfortunately the standards for transaction management, as well as workflow (or business process management), are still evolving, so it will be confusing for a while.
But it's good to have choices. And even now, things that appear synchronous aren't always what they seem. Ask anyone who has my instant messaging address - see if they believe instant messaging is "instant." I can assure you, it isn't.
And the reality is, there is room, and a need for both programming paradigms within Web services. This issue explores those two approaches in depth. Now it's time for me to ignore some instant messages…
Jul. 30, 2016 07:30 PM EDT Reads: 3,994
Internet of @ThingsExpo, taking place November 1-3, 2016, at the Santa Clara Convention Center in Santa Clara, CA, is co-located with the 19th International Cloud Expo and will feature technical sessions from a rock star conference faculty and the leading industry players in the world and ThingsExpo Silicon Valley Call for Papers is now open.
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There's a lot of things we do to improve the performance of web and mobile applications. We use caching. We use compression. We offload security (SSL and TLS) to a proxy with greater compute capacity. We apply image optimization and minification to content. We do all that because performance is king. Failure to perform can be, for many businesses, equivalent to an outage with increased abandonment rates and angry customers taking to the Internet to express their extreme displeasure.
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Ovum, a leading technology analyst firm, has published an in-depth report, Ovum Decision Matrix: Selecting a DevOps Release Management Solution, 2016–17. The report focuses on the automation aspects of DevOps, Release Management and compares solutions from the leading vendors.
Jul. 30, 2016 01:00 PM EDT Reads: 1,857
No matter how well-built your applications are, countless issues can cause performance problems, putting the platforms they are running on under scrutiny. If you've moved to Node.js to power your applications, you may be at risk of these issues calling your choice into question. How do you identify vulnerabilities and mitigate risk to take the focus off troubleshooting the technology and back where it belongs, on innovation? There is no doubt that Node.js is one of today's leading platforms of ...
Jul. 30, 2016 12:45 PM EDT Reads: 799
Adding public cloud resources to an existing application can be a daunting process. The tools that you currently use to manage the software and hardware outside the cloud aren’t always the best tools to efficiently grow into the cloud. All of the major configuration management tools have cloud orchestration plugins that can be leveraged, but there are also cloud-native tools that can dramatically improve the efficiency of managing your application lifecycle. In his session at 18th Cloud Expo, ...
Jul. 30, 2016 12:00 PM EDT Reads: 1,365
SYS-CON Events announced today that LeaseWeb USA, a cloud Infrastructure-as-a-Service (IaaS) provider, will exhibit at the 19th International Cloud Expo, which will take place on November 1–3, 2016, at the Santa Clara Convention Center in Santa Clara, CA. LeaseWeb is one of the world's largest hosting brands. The company helps customers define, develop and deploy IT infrastructure tailored to their exact business needs, by combining various kinds cloud solutions.
Jul. 30, 2016 11:30 AM EDT Reads: 1,408
SYS-CON Events announced today that Venafi, the Immune System for the Internet™ and the leading provider of Next Generation Trust Protection, will exhibit at @DevOpsSummit at 19th International Cloud Expo, which will take place on November 1–3, 2016, at the Santa Clara Convention Center in Santa Clara, CA. Venafi is the Immune System for the Internet™ that protects the foundation of all cybersecurity – cryptographic keys and digital certificates – so they can’t be misused by bad guys in attacks...
Jul. 30, 2016 10:15 AM EDT Reads: 1,524
DevOps at Cloud Expo – being held November 1-3, 2016, at the Santa Clara Convention Center in Santa Clara, CA – announces that its Call for Papers is open. Born out of proven success in agile development, cloud computing, and process automation, DevOps is a macro trend you cannot afford to miss. From showcase success stories from early adopters and web-scale businesses, DevOps is expanding to organizations of all sizes, including the world's largest enterprises – and delivering real results. Am...
Jul. 30, 2016 05:45 AM EDT Reads: 2,401
Let's just nip the conflation of these terms in the bud, shall we?
"MIcro" is big these days. Both microservices and microsegmentation are having and will continue to have an impact on data center architecture, but not necessarily for the same reasons. There's a growing trend in which folks - particularly those with a network background - conflate the two and use them to mean the same thing.
They are not.
One is about the application. The other, the network. T...
Jul. 30, 2016 05:15 AM EDT Reads: 3,771
The 19th International Cloud Expo has announced that its Call for Papers is open. Cloud Expo, to be held November 1-3, 2016, at the Santa Clara Convention Center in Santa Clara, CA, brings together Cloud Computing, Big Data, Internet of Things, DevOps, Digital Transformation, Microservices and WebRTC to one location. With cloud computing driving a higher percentage of enterprise IT budgets every year, it becomes increasingly important to plant your flag in this fast-expanding business opportuni...
Jul. 30, 2016 05:15 AM EDT Reads: 2,728
If you are within a stones throw of the DevOps marketplace you have undoubtably noticed the growing trend in Microservices. Whether you have been staying up to date with the latest articles and blogs or you just read the definition for the first time, these 5 Microservices Resources You Need In Your Life will guide you through the ins and outs of Microservices in today’s world.
Jul. 30, 2016 04:30 AM EDT Reads: 4,205
Before becoming a developer, I was in the high school band. I played several brass instruments - including French horn and cornet - as well as keyboards in the jazz stage band. A musician and a nerd, what can I say? I even dabbled in writing music for the band. Okay, mostly I wrote arrangements of pop music, so the band could keep the crowd entertained during Friday night football games. What struck me then was that, to write parts for all the instruments - brass, woodwind, percussion, even k...
Jul. 30, 2016 01:45 AM EDT Reads: 2,425
This digest provides an overview of good resources that are well worth reading. We’ll be updating this page as new content becomes available, so I suggest you bookmark it. Also, expect more digests to come on different topics that make all of our IT-hearts go boom!
Jul. 30, 2016 12:45 AM EDT Reads: 3,795
Keeping pace with advancements in software delivery processes and tooling is taxing even for the most proficient organizations. Point tools, platforms, open source and the increasing adoption of private and public cloud services requires strong engineering rigor – all in the face of developer demands to use the tools of choice. As Agile has settled in as a mainstream practice, now DevOps has emerged as the next wave to improve software delivery speed and output. To make DevOps work, organization...
Jul. 30, 2016 12:30 AM EDT Reads: 2,368
SYS-CON Events announced today that Isomorphic Software will exhibit at DevOps Summit at 19th International Cloud Expo, which will take place on November 1–3, 2016, at the Santa Clara Convention Center in Santa Clara, CA. Isomorphic Software provides the SmartClient HTML5/AJAX platform, the most advanced technology for building rich, cutting-edge enterprise web applications for desktop and mobile. SmartClient combines the productivity and performance of traditional desktop software with the simp...
Jul. 29, 2016 10:00 PM EDT Reads: 1,309
Right off the bat, Newman advises that we should "think of microservices as a specific approach for SOA in the same way that XP or Scrum are specific approaches for Agile Software development". These analogies are very interesting because my expectation was that microservices is a pattern. So I might infer that microservices is a set of process techniques as opposed to an architectural approach. Yet in the book, Newman clearly includes some elements of concept model and architecture as well as p...
Jul. 29, 2016 02:45 PM EDT Reads: 9,844
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Jul. 29, 2016 04:15 AM EDT Reads: 4,299
In his session at @DevOpsSummit at 19th Cloud Expo, Yoseph Reuveni, Director of Software Engineering at Jet.com, will discuss Jet.com's journey into containerizing Microsoft-based technologies like C# and F# into Docker. He will talk about lessons learned and challenges faced, the Mono framework tryout and how they deployed everything into Azure cloud. Yoseph Reuveni is a technology leader with unique experience developing and running high throughput (over 1M tps) distributed systems with extre...
Jul. 28, 2016 10:15 PM EDT Reads: 2,268
Sharding has become a popular means of achieving scalability in application architectures in which read/write data separation is not only possible, but desirable to achieve new heights of concurrency. The premise is that by splitting up read and write duties, it is possible to get better overall performance at the cost of a slight delay in consistency. That is, it takes a bit of time to replicate changes initiated by a "write" to the read-only master database. It's eventually consistent, and it'...
Jul. 28, 2016 08:30 PM EDT Reads: 2,381