Click here to close now.


Microservices Expo Authors: Liz McMillan, Victoria Livschitz, Pat Romanski, Pete Waterhouse, Elizabeth White

Related Topics: Microservices Expo

Microservices Expo: Article

ESB Myth Busters: 10 Enterprise Service Bus Myths Debunked

Clarity of Definition for a Growing Phenomenon

Since releasing my latest book, Enterprise Service Bus (O'Reilly Media, 2004), I have been doing a fair amount of visiting corporations, conducting seminars, and generally discussing with enterprise architects the subject of enterprise service-oriented architecture (SOA) and how an enterprise service bus (ESB) backbone can be leveraged to provide a framework for an enterprise SOA. Along the way, I have been asked many questions about the nature of an ESB. I have also fended off some misconceptions that have been growing in the general IT population regarding what an ESB is and when, where, and how it can be used. I have gathered together the most popular questions and misconceptions, and offer some clarity in the form of a "top ten" list.

Myth #1. ESB is just a new name for EAI.
While many IT architecture groups are focusing on building SOAs, they still inevitably beg the question of "how is ESB different from EAI?" An ESB is an infrastructure for building an enterprise SOA, and is capable of being used in a more general way than a conventional EAI broker. According to Forrester Research, an ESB helps enterprises obtain the value of SOA by increasing connectivity, adding flexibility that speeds change, and providing greater control over use of the important resources that it binds.

An ESB can be used to handle integration projects that have traditionally been relegated to EAI tools. However, an ESB can also be used for establishing B2B relationships across companies.

An ESB provides EAI capabilities, but is based on a fundamentally different architecture that is providing the basis of an industry transition from traditional integration to coordinated service interaction. EAI brokers are historically implemented as a monolithic stack, using centralized hub-and-spoke architecture.

An ESB provides the same base functionality as an EAI broker - connectivity, application adapters, routing of messages based on rules, and data transformation engine - yet, in an ESB, these capabilities are themselves SOA based in that they are spread out across the bus in a highly distributed fashion and hosted in separately deployable service containers. This allows the selective deployment of integration broker functionality exactly where you need it, with no additional over-bloating where it's not needed. The distributed nature of the ESB container model allows the independent scalability of integration components, which are plugged into your SOA as event-driven services on an as needed basis.

In order for an integration broker to be truly capable of supporting an SOA, and to be considered a true ESB, it would need to have its base functions broken up into their constituent parts, which would then be capable of being separately deployed across the bus while working together in harmony as necessary.

Let's use an example of an XSLT-based transformation engine that accepts an incoming XML document and applies an XSLT style sheet to it in order to produce an outgoing document in another XML format. I can tell you that there is nothing that can chew up computing resources more than the parsing and manipulation of XML. If this particular XSLT transformation sits between two popular applications that communicate regularly with each other, then that individual transformation can become a performance and scalability bottleneck. If you are using a monolithic hub-and-spoke integration broker approach, in order to remove the bottleneck and scale up the deployment you would need to either install that integration broker on one big powerful machine, or install the integration broker across multiple machines - just to support that one transform scenario! All the while, the other integration broker capabilities, such as the execution of routing rules, are competing for the same computing resources as the transformation operation.

In contrast to the monolithic hub-and-spoke architecture of an integration broker, the foundational core of an ESB provides a distributed services architecture. This architecture is built for integration and has the ability for integration broker functionality, such as message routing, data transformation, and application adapters to be selectively deployed on an as-needed basis.These are separate integration services that are a natural part of an SOA processing pipeline across the bus.

An individual XSLT transformation can be deployed as a service in its own ESB service container, and multiple instances of that container can be load-balanced across many machines. If the ESB container implementation is cross-platform, then you can be flexible as to what kinds of machines you spread the transform service across - Linux boxes, Solaris boxes, Windows boxes, and so on. And for those of you who don't find solace in the architectural purity of this discussion, consider this: the ESB vendors who are leading the charge in defining and delivering ESB products are also putting forth a license model where there is no additional cost for deploying as many of these lightweight ESB service containers as necessary to get the job done.

The integration services provided by the ESB can be combined with other services into SOA-based processing pipelines that can span business boundaries. The distributed services in an ESB can be combined with itinerary-based routing (see Myth #7) to allow self-directed, message-oriented service interactions, which allow different parts of the ESB to operate independently of one another, without relying on a centralized routing engine.

More Stories By Dave Chappell

David Chappell is vice president and chief technologist for SOA at Oracle Corporation, and is driving the vision for Oracle’s SOA on App Grid initiative.

Comments (8) View Comments

Share your thoughts on this story.

Add your comment
You must be signed in to add a comment. Sign-in | Register

In accordance with our Comment Policy, we encourage comments that are on topic, relevant and to-the-point. We will remove comments that include profanity, personal attacks, racial slurs, threats of violence, or other inappropriate material that violates our Terms and Conditions, and will block users who make repeated violations. We ask all readers to expect diversity of opinion and to treat one another with dignity and respect.

Most Recent Comments
Charlesy 07/03/13 07:28:00 AM EDT

An old post, but worth a small correction. Comparison with competitor products is always dangerous. You need to be very sure of your territory, and unfortunately, although David's description of BizTalk Server has some validity, it isn't 100% accurate. For example, the transformation services absolutely can be invoked separately to the rest of BTS via lightweight services, and load balanced across different boxes. More recent versions of BTS provide pre-built generic WCF and ASMX transformation web services as a courtesy to developers (reduces the need to build custom transformation services). You can use Windows Server AppFabric tools to create BizTalk maps in non-BizTalk projects - e.g., projects that define lightweight transformation services.

David doesn't clearly spell out what he means by 'cost...of the entire BizTalk Server'. If he means licencing cost, then he hits the mark, somewhat. BTS is certainly licensed in a fashion that encourages distribution and load balancing over a small farm of centralized servers, in contrast to the highly distributed approach advocated by Sonic. You can only invoke BTS transformation services on licensed boxes, so from that perspective, he is correct. However, invoking the transformation services does not require loading additional irrelevant BTS plumbing into memory. There is no heavy-weight performance cost imposed by code bloat, or anything like that!

BizTalk maps are emitted as code components containing an executable XSLT resource. You can distribute maps as freely as you wish and invoke the tranforms via code. Obviously, direct invocation in this case assumes the use of either .NET or Mono, although Java/.NET bridges could be used. If you use BizTalk Server's mapping tools to create maps, you may end up with a dependency on BizTalk-specific scripted components invoked in the XSLT, which ties you to licensed BizTalk Boxes. However, it is pretty easy to avoid this if you wish.

One thing Sonic has which BizTalk really does not is dynamic management of code deployment into the run-time environment. BizTalk Server has an built-in code repository, but this is simply a mechanism for managing and storing compiled artifacts and resources for the purpose of exporting installation packages. You still have to manually install those packages or deploy them via additional script. Frankly, though, this is rarely a significant drawback. The types of solution built using BizTalk Server tend to warrant close attention to managing dynamic deployment across a distributed environment using other frameworks and tools, and BizTalk Server plays well with the relevant frameworks. There is even a community-built deployment framework specifically designed for BizTalk Server.

yt67 03/03/05 07:09:34 AM EST

Myth-busting: always entertaining.

Jason 03/02/05 09:16:29 AM EST

A good read!

Javier Camara 02/10/05 04:19:02 AM EST

(This same feedback also posted to another WSJ article about ESBs)

I agree in that the ESB concept is over-hyped. For me, a SOA makes sense if it is viewed as a constellation of web services interacting among them. For this, something like a UDDI server is required for each service locating each other.

For me, all this (i.e. services + directory) is just enough if only synchronous communications are used. If asynchronous communications are needed, then you need also publish/subscribe and store-and-forward, i.e. roughly what a MOM does. You can call it an ESB if you want, although I think this concept in the market encompasses several roles:
1. Publish/subscribe to messages
2. Store-and-forward messages
3. Route messages
4. Transform messages

An interesting thing to note is to implement points 1. and 2. you do *not* need business logic, while to implement 3. and 4. you do.

As I said, I see roles 1 and 2 required in SOAs with asynchronous interactions.

Roles 3 and 4 are also needed in many cases, mainly for integrating disparate systems. However, my main point against an ESB is that, in order to perform these roles, you do *NOT* need of a new, special concept like the ESB. *Any* service in the constellation of services can perform both routing and transformation. It can range from being a single component like an ESB (which I think is a bad idea), or it can just be a set of services (e.g. a different service performing specific adaptation for a system being integrated).

For me, using a single ESB for 3. and 4. breaks the beauty of the SOA idea. You are supposed to made all your data and business logic of your organization available as services in order to be reused, and suddenly you put on top an ESB in which you put *more* business logic (routing and transformation). So my point is that this should be implemented just by means of regular services, and not by specific, central-piece new components called ESBs.

Now, if for implementing routing and transformation you want to use Tibco, WebSphere or whatever, fine - however, the logic created by these products should be at the same level as the other services in the SOA, and not above.

So I am not saying that orchestrating tools are not useful. They are. Only, they are not *imprescindible*; and at any rate they should be viewed just as more services in the SOA. However, this does not fit the marketing strategy of ESB vendors which show its ESB as an *enabler* of a SOA, instead of just one more *component* of it.

Dave Chappell 02/03/05 09:54:43 PM EST

We (Sonic Software) didn't re-lable our product to support the ESB wave, we actually invented the concept. We then worked with the analyst and journalist community to help create industry awareness of the new concepts that are introduced by ESB, which has resulted in a whole new product category.

I would agree with you that there is a great deal of hype right now due to lack of understanding of what ESB is, which is compounded by the number of traditional middleware and EAI vendors who have clamoured to get ESB in their marketing literature without having a full understanding of what it means to have an ESB. Your comment about middleware with new clothes is well taken. You might get that impression depending on where you learned about what an ESB is. That is exactly what I am trying to point out with myth #1 in this article.

A certain amount of hype is expected when a technology category begins to take hold and gain traction within serious IT projects. This can be disruptive to the industry as a whole. This is also the primary reason why I wrote the OReilly book on the subject of ESB--to act as the definitive guide to help educate and provide clarity on what makes up an ESB. Please don't shoot the concept of ESB down until you have had a chance to understand it.

Larry 02/03/05 04:15:19 AM EST

Not surprising that the representative of a company who over-hyped ESB in the first place, and relabeled their own product ESB to catch the service wave, should now try to claim that anyone who saw through the hype is guilty of spreading myths.
ESB is just the middleware emporor's new clothes.

@MicroservicesExpo Stories
Apps and devices shouldn't stop working when there's limited or no network connectivity. Learn how to bring data stored in a cloud database to the edge of the network (and back again) whenever an Internet connection is available. In his session at 17th Cloud Expo, Bradley Holt, Developer Advocate at IBM Cloud Data Services, will demonstrate techniques for replicating cloud databases with devices in order to build offline-first mobile or Internet of Things (IoT) apps that can provide a better, ...
DevOps Summit at Cloud Expo 2014 Silicon Valley was a terrific event for us. The Qubell booth was crowded on all three days. We ran demos every 30 minutes with folks lining up to get a seat and usually standing around. It was great to meet and talk to over 500 people! My keynote was well received and so was Stan's joint presentation with RingCentral on Devops for BigData. I also participated in two Power Panels – ‘Women in Technology’ and ‘Why DevOps Is Even More Important than You Think,’ both ...
Clearly the way forward is to move to cloud be it bare metal, VMs or containers. One aspect of the current public clouds that is slowing this cloud migration is cloud lock-in. Every cloud vendor is trying to make it very difficult to move out once a customer has chosen their cloud. In his session at 17th Cloud Expo, Naveen Nimmu, CEO of Clouber, Inc., will advocate that making the inter-cloud migration as simple as changing airlines would help the entire industry to quickly adopt the cloud wit...
“All our customers are looking at the cloud ecosystem as an important part of their overall product strategy. Some see it evolve as a multi-cloud / hybrid cloud strategy, while others are embracing all forms of cloud offerings like PaaS, IaaS and SaaS in their solutions,” noted Suhas Joshi, Vice President – Technology, at Harbinger Group, in this exclusive Q&A with Cloud Expo Conference Chair Roger Strukhoff.
Docker is hot. However, as Docker container use spreads into more mature production pipelines, there can be issues about control of Docker images to ensure they are production-ready. Is a promotion-based model appropriate to control and track the flow of Docker images from development to production? In his session at DevOps Summit, Fred Simon, Co-founder and Chief Architect of JFrog, will demonstrate how to implement a promotion model for Docker images using a binary repository, and then show h...
Culture is the most important ingredient of DevOps. The challenge for most organizations is defining and communicating a vision of beneficial DevOps culture for their organizations, and then facilitating the changes needed to achieve that. Often this comes down to an ability to provide true leadership. As a CIO, are your direct reports IT managers or are they IT leaders? The hard truth is that many IT managers have risen through the ranks based on their technical skills, not their leadership ab...
Jack Welch, the former CEO of GE once said - “If the rate of change on the outside is happening faster than the rate of change on the inside, the end is in sight.” This rings truer than ever – especially because business success is inextricably associated with those organizations who’ve got really good at delivering high-quality software innovations – innovations that disrupt existing markets and carve out new ones. Like the businesses they’ve helped digitally transform, DevOps teams and Conti...
This week, the team assembled in NYC for @Cloud Expo 2015 and @ThingsExpo 2015. For the past four years, this has been a must-attend event for MetraTech. We were happy to once again join industry visionaries, colleagues, customers and even competitors to share and explore the ways in which the Internet of Things (IoT) will impact our industry. Over the course of the show, we discussed the types of challenges we will collectively need to solve to capitalize on the opportunity IoT presents.
SYS-CON Events announced today that Alert Logic, the leading provider of Security-as-a-Service solutions for the cloud, has been named “Bronze Sponsor” of SYS-CON's 17th International Cloud Expo® and DevOps Summit 2015 Silicon Valley, which will take place November 3–5, 2015, at the Santa Clara Convention Center in Santa Clara, CA. Alert Logic provides Security-as-a-Service for on-premises, cloud, and hybrid IT infrastructures, delivering deep security insight and continuous protection for cust...
Application availability is not just the measure of “being up”. Many apps can claim that status. Technically they are running and responding to requests, but at a rate which users would certainly interpret as being down. That’s because excessive load times can (and will be) interpreted as “not available.” That’s why it’s important to view ensuring application availability as requiring attention to all its composite parts: scalability, performance, and security.
SYS-CON Events announced today that HPM Networks will exhibit at the 17th International Cloud Expo®, which will take place on November 3–5, 2015, at the Santa Clara Convention Center in Santa Clara, CA. For 20 years, HPM Networks has been integrating technology solutions that solve complex business challenges. HPM Networks has designed solutions for both SMB and enterprise customers throughout the San Francisco Bay Area.
All we need to do is have our teams self-organize, and behold! Emergent design and/or architecture springs up out of the nothingness! If only it were that easy, right? I follow in the footsteps of so many people who have long wondered at the meanings of such simple words, as though they were dogma from on high. Emerge? Self-organizing? Profound, to be sure. But what do we really make of this sentence?
DevOps is speeding towards the IT world like a freight train and the hype around it is deafening. There is no reason to be afraid of this change as it is the natural reaction to the agile movement that revolutionized development just a few years ago. By definition, DevOps is the natural alignment of IT performance to business profitability. The relevance of this has yet to be quantified but it has been suggested that the route to the CEO’s chair will come from the IT leaders that successfully ma...
Somebody call the buzzword police: we have a serious case of microservices-washing in progress. The term “microservices-washing” is derived from “whitewashing,” meaning to hide some inconvenient truth with bluster and nonsense. We saw plenty of cloudwashing a few years ago, as vendors and enterprises alike pretended what they were doing was cloud, even though it wasn’t. Today, the hype around microservices has led to the same kind of obfuscation, as vendors and enterprise technologists alike ar...
I’ve been thinking a bit about microservices (μServices) recently. My immediate reaction is to think: “Isn’t this just yet another new term for the same stuff, Web Services->SOA->APIs->Microservices?” Followed shortly by the thought, “well yes it is, but there are some important differences/distinguishing factors.” Microservices is an evolutionary paradigm born out of the need for simplicity (i.e., get away from the ESB) and alignment with agile (think DevOps) and scalable (think Containerizati...
The cloud has reached mainstream IT. Those 18.7 million data centers out there (server closets to corporate data centers to colocation deployments) are moving to the cloud. In his session at 17th Cloud Expo, Achim Weiss, CEO & co-founder of ProfitBricks, will share how two companies – one in the U.S. and one in Germany – are achieving their goals with cloud infrastructure. More than a case study, he will share the details of how they prioritized their cloud computing infrastructure deployments ...
Mobile has become standard in the enterprise with smartphones and tablets common in the workplace. Anywhere, anytime access to company systems is expected and systems must work flawlessly on these devices! This demand is requiring that corporate IT departments figure out the best mobile strategy to follow. This eBook looks at how to kick start your mobile application strategy.
Even though you are running an agile development process, that doesn’t necessarily mean that your performance testing is being conducted in a truly agile way. Saving performance testing for a “final sprint” before release still treats it like a waterfall development step, with all the cost and risk that comes with that. In this post, we will show you how to make load testing happen early and often by putting SLAs on the agile task board.
Today, we are in the middle of a paradigm shift as we move from managing applications on VMs and containers to embracing everything that the cloud and XaaS (Everything as a Service) has to offer. In his session at 17th Cloud Expo, Kevin Hoffman, Advisory Solutions Architect at Pivotal Cloud Foundry, will provide an overview of 12-factor apps and migrating enterprise apps to the cloud. Kevin Hoffman is an Advisory Solutions Architect for Pivotal Cloud Foundry, and has spent the past 20 years b...
Go ahead. Name a cloud environment that doesn't include load balancing as the key enabler of elastic scalability. I've got coffee... so it's good, take your time... Exactly. Load balancing - whether implemented as traditional high availability pairs or clustering - provides the means by which applications (and infrastructure, in many cases) scale horizontally. It is load balancing that is at the heart of elastic scalability models, and that provides a means to ensure availability and even imp...