Click here to close now.

Welcome!

SOA & WOA Authors: Liz McMillan, Carmen Gonzalez, Roger Strukhoff, Dana Gardner, Tim Hinds

Related Topics: SOA & WOA

SOA & WOA: Article

SOA Feature Story: Real-Time SOA Starts with the Messaging Bus!

The mediator of all component interactions

Service Oriented Architectures are increasingly being used to implement high-performance and real-time systems. Traditional systems operate in "human real-time," where human patience is the limit. Increasingly, however, systems operate in "computer real-time," where the only limits are imposed by the operational speed of the computers and networks.

For example, next-generation Air Traffic Management systems are being developed to accommodate the huge increase in air traffic and link the operational capabilities of agencies such as the Federal Aviation Authority, the Department of Defense (DOD) and the Department of Homeland Security (DHS). These systems require higher information bandwidth (to track more aircraft or more complex "free-flight" trajectories) as well as much lower latencies or delays on the information (to detect flight abnormalities quickly). Similar demands are being made in healthcare, SCADA, network monitoring, energy distribution, transportation, and other critical infrastructure systems.

Best-of-Breed SOA Components
Demanding real-time applications require best-of-breed service-oriented foundational components. There are three kinds of foundational components in a SOA system: A messaging fabric/bus, information transformation/processing engines, and persistence/storage services (see Figure 1). Often these components are integrated into an Enterprise Service Bus (ESB) and hosted in a J2EE Application Server.

Of these foundational components, the Messaging Fabric/Bus is the most critical, since it mediates all interactions between components.

Low-performance SOA systems may use HTTP as the "messaging fabric/bus" to exchange messages between components. This approach is only suitable for non-demanding applications: HTTP isn't reliable, has limited bandwidth, introduces very high latencies, and can't buffer and queue messages and deliver them to systems that are either temporarily unavailable or join at a later time.

The solution is to deploy a high-performance messaging middleware such as RTI Data-Distribution Service, IBM WebSphere MQ, TIBCO, or SonicMQ. These middleware platforms have been developed with scalability and performance in mind. However, they each employ a different architecture optimized for different application scenarios.

Why Does Messaging Performance Matter?
The requirements and expectations of computer-speed real-time far exceed traditional human-speed real-time. Whereas in systems with a human in the loop, real-time meant that the information was available anywhere from fractions of a second to few seconds in the computer-to-computer world, real-time means decisions should be made in milliseconds or even microseconds.

Computer real-time puts more stringent requirements on the messaging infrastructure: Each processing and storage component must get hundreds of thousands of messages/events per second with microsecond or at worst millisecond latencies. This means that the messaging middleware must be able to deliver millions of messages a second system-wide.

And the capacity of the messaging fabric must be able to scale with the capacity of the underlying hardware and not impose any limits beyond those of the underlying hardware infrastructure (CPU speed, cores, speed, and bandwidth of the network) itself. As the CPU and network speeds increase those systems able to take advantage of what the hardware provides will deliver a competitive advantage. In an automated trading system, for instance, the critical metric is not the absolute time it takes to make a decision, but rather whether a decision is taken and the trade executed before competitive trades occur. The same is true in a combat management system.

One final aspect of computer real-time SOA systems is their "inverted performance-load utility curve." This means that the ability to respond in a timely manner becomes more important when the system is experiencing a high load. In a normal utility curve, such as in human real-time systems, degraded performance is acceptable under an increased load. This is because human expectations and patience adjust based on the circumstances (e.g., they understand that on a peak holiday period they may endure longer hold times when calling to make a flight reservation). In contrast, computer-speed real-time systems often have the opposite demands. It is precisely at the moments of high load when the "most critical action" is taking place and it is then when it is most critical to deliver top performance (e.g., it is precisely when market action is heavy that trading decisions must be made quickly).

The differences between human-speed real-time systems and computer-speed real-time systems are summarized in Table 1.

Selecting Messaging Middleware in SOA Systems
Messaging middleware is the key enabler of real-time SOA. However, there are many options. How can you choose the best messaging middleware for a particular real-time SOA system? Five areas distinguish messaging middleware: architecture, quality of service (QoS) control and filters, performance-boosting technologies, real-time determinism, and metrics.

Architecture
The four basic architectures employed by messaging middleware are: centralized (hub-and-spoke), clustered, federated, and peer-to-peer. (see Figure 2)

A centralized (hub-and-spoke) architecture routes every message though a single server that implements the message "service," contains all the message queues, and brokers every message.
A clustered architecture uses a collection of servers and assigns to each responsibility for some of the messages (like ownership of some of the message queues or topics). Each message is relayed by a server but not all messages use the same server.

A federated architecture also uses a collection of servers, but it uses them as a "resource pool" where queues may appear in multiple servers, and messages may be brokered by one or more servers.

A peer-to-peer architecture doesn't employ any brokers in the critical path. Messages are routed directly from the sender to the receiver.

Each has strengths and weaknesses. Centralized is easiest to administer and can provide stronger transactional semantics but suffers from poor performance, reduced tolerance to faults, and doesn't scale. Clustered is more scalable than centralized but also has reduced fault tolerance and can only offer good performance in a grid environment with all the clients co-located close to the grid. Federated is more scalable, but suffers from higher latency and jitter as each message is brokered by at least two servers. P2P offers the best scalability, performance, lowest jitter, and highest resilience, but is difficult for vendors to implement and offers limited transactional support.

As demands become more real-time, the need for performance, predictability, and balance tips the scale towards P2P architecture. That's why, for example, demanding networks like Voice over IP and Video over IP (like Skype) use peer-to-peer designs.

Quality of Service Control & Filters
QoS control is critical to deliver timely data with low latency and high throughput. CPU, memory, and network bandwidth resources must be shared among all the traffic. However, not all traffic requires the same bandwidth or has the same urgency or level or criticality. Without QoS control, the application has no way to differentiate different traffic classes and their corresponding constraints. As a consequence, the middleware can't make intelligent decisions, prioritize traffic, or ultimately meet the application requirements.


More Stories By Gerardo Pardo-Castellote

Gerardo Pardo-Castellote, PhD, is chief technology officer of Real-Time Innovations Inc.

Comments (3) 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
Gerardo Pardo-Castellote 07/20/08 01:57:08 AM EDT

Regarding the previous comment about "TCP not lining up a message on one connection after a file transfer on another connection." and the "information in the article not being correct."

This is true, but in order for this to occur you would need to open a new TCP connection for every message. This is extremely inefficient, requires a handshake involving a round-trip message, and allocates a lot of system resources. This is certainly something you do not want to do in a real-time system.

So in practice anybody developing a real-time system would have to hold the TCP connection open and send successive messages over it (or course one can keep more than one connection open, and round-robin among them but that does not change fundamental problem if the application is writing quickly). Therefore the information in the article IS correct.

Casual Visitor 06/12/08 03:04:45 PM EDT

TCP does not line up a message on one connection after a file transfer on another connection. Each TCP connection forms its own in-order transfer. If you want to convince people to buy your product, you should avoid putting incorrect information in the article. It is much better to have a good analysis with accurate claims so that people will believe that your product might overcome real problems rather than phantom ones like "messages wait behind file transfers".

Derek Pavatte 01/25/08 02:03:32 AM EST

If everything is automated, I suppose we will have more time to do things more pleasant things than work as much. These technological advancements sound very progressive. Let us all work towards a competent and ethical work environment.
http://www.greatdiamondsforless.com

@ThingsExpo Stories
The Internet of Everything (IoE) brings together people, process, data and things to make networked connections more relevant and valuable than ever before – transforming information into knowledge and knowledge into wisdom. IoE creates new capabilities, richer experiences, and unprecedented opportunities to improve business and government operations, decision making and mission support capabilities. In his session at @ThingsExpo, Gary Hall, Chief Technology Officer, Federal Defense at Cisco Systems, will break down the core capabilities of IoT in multiple settings and expand upon IoE for bo...
The explosion of connected devices / sensors is creating an ever-expanding set of new and valuable data. In parallel the emerging capability of Big Data technologies to store, access, analyze, and react to this data is producing changes in business models under the umbrella of the Internet of Things (IoT). In particular within the Insurance industry, IoT appears positioned to enable deep changes by altering relationships between insurers, distributors, and the insured. In his session at @ThingsExpo, Michael Sick, a Senior Manager and Big Data Architect within Ernst and Young's Financial Servi...
SYS-CON Events announced today that Vitria Technology, Inc. will exhibit at SYS-CON’s @ThingsExpo, which will take place on June 9-11, 2015, at the Javits Center in New York City, NY. Vitria will showcase the company’s new IoT Analytics Platform through live demonstrations at booth #330. Vitria’s IoT Analytics Platform, fully integrated and powered by an operational intelligence engine, enables customers to rapidly build and operationalize advanced analytics to deliver timely business outcomes for use cases across the industrial, enterprise, and consumer segments.
The Internet of Things (IoT) is causing data centers to become radically decentralized and atomized within a new paradigm known as “fog computing.” To support IoT applications, such as connected cars and smart grids, data centers' core functions will be decentralized out to the network's edges and endpoints (aka “fogs”). As this trend takes hold, Big Data analytics platforms will focus on high-volume log analysis (aka “logs”) and rely heavily on cognitive-computing algorithms (aka “cogs”) to make sense of it all.
SYS-CON Events announced today that GENBAND, a leading developer of real time communications software solutions, has been named “Silver Sponsor” of SYS-CON's WebRTC Summit, which will take place on June 9-11, 2015, at the Javits Center in New York City, NY. The GENBAND team will be on hand to demonstrate their newest product, Kandy. Kandy is a communications Platform-as-a-Service (PaaS) that enables companies to seamlessly integrate more human communications into their Web and mobile applications - creating more engaging experiences for their customers and boosting collaboration and productiv...
From telemedicine to smart cars, digital homes and industrial monitoring, the explosive growth of IoT has created exciting new business opportunities for real time calls and messaging. In his session at @ThingsExpo, Ivelin Ivanov, CEO and Co-Founder of Telestax, shared some of the new revenue sources that IoT created for Restcomm – the open source telephony platform from Telestax. Ivelin Ivanov is a technology entrepreneur who founded Mobicents, an Open Source VoIP Platform, to help create, deploy, and manage applications integrating voice, video and data. He is the co-founder of TeleStax, a...
The industrial software market has treated data with the mentality of “collect everything now, worry about how to use it later.” We now find ourselves buried in data, with the pervasive connectivity of the (Industrial) Internet of Things only piling on more numbers. There’s too much data and not enough information. In his session at @ThingsExpo, Bob Gates, Global Marketing Director, GE’s Intelligent Platforms business, to discuss how realizing the power of IoT, software developers are now focused on understanding how industrial data can create intelligence for industrial operations. Imagine ...
The explosion of connected devices / sensors is creating an ever-expanding set of new and valuable data. In parallel the emerging capability of Big Data technologies to store, access, analyze, and react to this data is producing changes in business models under the umbrella of the Internet of Things (IoT). In particular within the Insurance industry, IoT appears positioned to enable deep changes by altering relationships between insurers, distributors, and the insured. In his session at @ThingsExpo, Michael Sick, a Senior Manager and Big Data Architect within Ernst and Young's Financial Servi...
One of the biggest impacts of the Internet of Things is and will continue to be on data; specifically data volume, management and usage. Companies are scrambling to adapt to this new and unpredictable data reality with legacy infrastructure that cannot handle the speed and volume of data. In his session at @ThingsExpo, Don DeLoach, CEO and president of Infobright, will discuss how companies need to rethink their data infrastructure to participate in the IoT, including: Data storage: Understanding the kinds of data: structured, unstructured, big/small? Analytics: What kinds and how responsiv...
The 3rd International @ThingsExpo, co-located with the 16th International Cloud Expo - to be held June 9-11, 2015, at the Javits Center in New York City, NY - is now accepting submissions to demo smart cars on the Expo Floor. Smart car sponsorship benefits include general brand exposure and increasing engagement with the developer ecosystem.
Operational Hadoop and the Lambda Architecture for Streaming Data Apache Hadoop is emerging as a distributed platform for handling large and fast incoming streams of data. Predictive maintenance, supply chain optimization, and Internet-of-Things analysis are examples where Hadoop provides the scalable storage, processing, and analytics platform to gain meaningful insights from granular data that is typically only valuable from a large-scale, aggregate view. One architecture useful for capturing and analyzing streaming data is the Lambda Architecture, representing a model of how to analyze rea...
Since 2008 and for the first time in history, more than half of humans live in urban areas, urging cities to become “smart.” Today, cities can leverage the wide availability of smartphones combined with new technologies such as Beacons or NFC to connect their urban furniture and environment to create citizen-first services that improve transportation, way-finding and information delivery. In her session at @ThingsExpo, Laetitia Gazel-Anthoine, CEO of Connecthings, will focus on successful use cases.
Sensor-enabled things are becoming more commonplace, precursors to a larger and more complex framework that most consider the ultimate promise of the IoT: things connecting, interacting, sharing, storing, and over time perhaps learning and predicting based on habits, behaviors, location, preferences, purchases and more. In his session at @ThingsExpo, Tom Wesselman, Director of Communications Ecosystem Architecture at Plantronics, will examine the still nascent IoT as it is coalescing, including what it is today, what it might ultimately be, the role of wearable tech, and technology gaps stil...
Sensor-enabled things are becoming more commonplace, precursors to a larger and more complex framework that most consider the ultimate promise of the IoT: things connecting, interacting, sharing, storing, and over time perhaps learning and predicting based on habits, behaviors, location, preferences, purchases and more. In his session at @ThingsExpo, Tom Wesselman, Director of Communications Ecosystem Architecture at Plantronics, will examine the still nascent IoT as it is coalescing, including what it is today, what it might ultimately be, the role of wearable tech, and technology gaps stil...
SYS-CON Events announced today that SoftLayer, an IBM company, has been named “Gold Sponsor” of SYS-CON's 16th International Cloud Expo®, which will take place June 9-11, 2015 at the Javits Center in New York City, NY, and the 17th International Cloud Expo®, which will take place November 3–5, 2015 at the Santa Clara Convention Center in Santa Clara, CA. SoftLayer operates a global cloud infrastructure platform built for Internet scale. With a global footprint of data centers and network points of presence, SoftLayer provides infrastructure as a service to leading-edge customers ranging from ...
SYS-CON Events announced today that Open Data Centers (ODC), a carrier-neutral colocation provider, will exhibit at SYS-CON's 16th International Cloud Expo®, which will take place June 9-11, 2015, at the Javits Center in New York City, NY. Open Data Centers is a carrier-neutral data center operator in New Jersey and New York City offering alternative connectivity options for carriers, service providers and enterprise customers.
When it comes to the Internet of Things, hooking up will get you only so far. If you want customers to commit, you need to go beyond simply connecting products. You need to use the devices themselves to transform how you engage with every customer and how you manage the entire product lifecycle. In his session at @ThingsExpo, Sean Lorenz, Technical Product Manager for Xively at LogMeIn, will show how “product relationship management” can help you leverage your connected devices and the data they generate about customer usage and product performance to deliver extremely compelling and reliabl...
There’s Big Data, then there’s really Big Data from the Internet of Things. IoT is evolving to include many data possibilities like new types of event, log and network data. The volumes are enormous, generating tens of billions of logs per day, which raise data challenges. Early IoT deployments are relying heavily on both the cloud and managed service providers to navigate these challenges. Learn about IoT, Big Data and deployments processing massive data volumes from wearables, utilities and other machines.
The true value of the Internet of Things (IoT) lies not just in the data, but through the services that protect the data, perform the analysis and present findings in a usable way. With many IoT elements rooted in traditional IT components, Big Data and IoT isn’t just a play for enterprise. In fact, the IoT presents SMBs with the prospect of launching entirely new activities and exploring innovative areas. CompTIA research identifies several areas where IoT is expected to have the greatest impact.
Wearable devices have come of age. The primary applications of wearables so far have been "the Quantified Self" or the tracking of one's fitness and health status. We propose the evolution of wearables into social and emotional communication devices. Our BE(tm) sensor uses light to visualize the skin conductance response. Our sensors are very inexpensive and can be massively distributed to audiences or groups of any size, in order to gauge reactions to performances, video, or any kind of presentation. In her session at @ThingsExpo, Jocelyn Scheirer, CEO & Founder of Bionolux, will discuss ho...