|By Lori MacVittie||
|May 27, 2014 09:00 AM EDT||
When people write about software-defined architectures being "disruptive" to the network they're doing a bit of a disservice to just how much change is occurring under the hood in the engine that drives today's businesses. The notion of separating control and data planes is superficial in that it describes a general concept and it isn't really all that radical a change, if you think about it.
The control and data planes have always been separate. We have, since the need for web-scale networks came about, implemented separate topological (and usually physical) networks specifically for the purpose of segregating control traffic from the data path. The reasons for this are many: to keep management (control) traffic from interfering with the delivery of applications (and vice versa), to enable a model in which control over the critical path for applications could be secured and to ensure access to necessary control functions in the face of failure or attack.
What's new with software-defined architectures is not just the logical separation but the physical decoupling and change in component responsibility. In traditional networks there is a logically separate control plane, but it is distributed; it resides on each physical component. In software-defined networks it is physically separate but it is centralized; control responsibility resides in a single component, the "controller".
Now, OpenStack and emerging models for scaling systems that will be responsible for managing communication with and for the Internet of Things (like MQTT) use a similar control model, but it's not as active as a software-defined architectural model, it's more a passive model. That's the nature of PubSub imposing itself on the network.
PubSub (publish / subscribe) is a familiar model to application developers. It's a middleware staple that's been used for a very long time to distribute messages to a variable set of systems. In a nutshell, PubSub is based on the notion of there existing a "queue" to which authorized components can publish events or messages of interest and to which interested components an subscribe. Events or messages have a life (like a TTL) and eventually expire. In the interim, it's expected that subscribed components check the queue for messages periodically. They poll for events or messages.
The queue itself is much like a switch or router's queue, except messages in the queue are duplicated until the TTL runs out and the message expires.
PubSub is passive; that is, it does not actively distribute messages. It merely serves as a kind of centralized repository, making available to those components that need it access to relevant information about the state of applications and/or the network.
Centralized Control Model
OpenFlow-based SDN, by contrast, is active. That is, it not only serves as a centralized repository for the state of applications and/or the network, but it actively distributes messages to components based on events. For example, a controller might receive a message from another system indicating the launch of a new application instance. That event triggers a series of actions on the controller that includes informing the affected network components of configuration changes. In a passive, PubSub model, the network components themselves might be polling for such an event and, upon receiving one, would initiate the appropriate configuration changes themselves.
We can simplify the description of the differences even more: a controller-based architecture uses a push model, while a pubsub-based architecture uses a pull model. What this doesn't illustrate well is that in a push model, the centralized controller must know how to communicate the desired changes to each and every component it is controlling. That's one of the reasons original models standardized on OpenFlow and were tightly focused on L2-4 stateless networking. It could be easily standardized down to a common forwarding table.While different components might internalize that differently, the basic information was always the same: IP addresses, ports and actions.
As we move up the stack into L4-7 stateful networking, however, this model becomes more burdensome because of the complexity of rule sets and differences in policy models across such a broad set of networking domains. Hence the plug-in support in controllers like OpenDaylight for "other" control protocols. But the basic premise of the model remains the same, regardless of the control protocol: the centralized controller dictates the changes to all components. It pushes those changes to the network. Both control and execution are centralized. The controller tells components to change their configuration.
PubSub centralizes control but decentralizes execution. The control plane is still centralized; there is one authoritative system responsible for disseminating change across the network, but each individual component (or domain controller but we'll get to that in a minute) is responsible for executing the appropriate changes based on their configured policies and services. A pubsub controller never tells a component "change this now"; that's up to the individual components (or domain controller).
The Integrated Control Model
To make things even more confusing (and disruptive), these models may be used simultaneously. A software-defined architecture might be based on a centralized control model with domain controllers for specific networking functions (like security and application delivery) integrated via a pubsub-based model.
This is where we start seeing models that combine emerging technologies like OpenStack and SDN architectures together. OpenStack manages at the data center level, and at its heart is pubsub model that can be used by domain controllers (stateless L2-4 SDN, stateful L4-7 SDN, etc...) to receive notification of changes in the network and subsequently push those changes using the appropriate control protocols to the components it is managing.
Needless to say, the term "disruptive" is really inadequate in describing the level of change in the network required to support either models (or both). Both require significant changes not just to the network itself but the way in which the network is fundamentally provisioned and managed. It's not just a new CLI or management console, these models dramatically change the design and management of networks.
[slides] From Industry to Society By @JMondanaro | @ThingsExpo @MetraTech @Ericsson #IoT #M2M #InternetOfThings
It is one thing to build single industrial IoT applications, but what will it take to build the Smart Cities and truly society-changing applications of the future? The technology won’t be the problem, it will be the number of parties that need to work together and be aligned in their motivation to succeed. In his session at @ThingsExpo, Jason Mondanaro, Director, Product Management at Metanga, discussed how you can plan to cooperate, partner, and form lasting all-star teams to change the world...
Jul. 7, 2015 07:00 PM EDT Reads: 2,614
SYS-CON Events announced today that Harbinger Systems will exhibit at SYS-CON's 17th International Cloud Expo®, which will take place on November 3–5, 2015, at the Santa Clara Convention Center in Santa Clara, CA. Harbinger Systems is a global company providing software technology services. Since 1990, Harbinger has developed a strong customer base worldwide. Its customers include software product companies ranging from hi-tech start-ups in Silicon Valley to leading product companies in the US a...
Jul. 7, 2015 05:45 PM EDT Reads: 2,503
Announcing @ProfitBricksUSA to Exhibit at @CloudExpo Silicon Valley | #IoT #API #DevOps #Microservices
SYS-CON Events announced today that ProfitBricks, the provider of painless cloud infrastructure, will exhibit at SYS-CON's 17th International Cloud Expo®, which will take place on November 3–5, 2015, at the Santa Clara Convention Center in Santa Clara, CA. ProfitBricks is the IaaS provider that offers a painless cloud experience for all IT users, with no learning curve. ProfitBricks boasts flexible cloud servers and networking, an integrated Data Center Designer tool for visual control over the...
Jul. 7, 2015 05:00 PM EDT Reads: 2,280
The 4th International Internet of @ThingsExpo, co-located with the 17th International Cloud Expo - to be held November 3-5, 2015, at the Santa Clara Convention Center in Santa Clara, CA - announces that its Call for Papers is open. The Internet of Things (IoT) is the biggest idea since the creation of the Worldwide Web more than
Jul. 7, 2015 05:00 PM EDT Reads: 2,305
"CenturyLink brings a full suite of services to the table and that enables us to be an IT service provider," explained Jeff Katzen, Director of the Cloud Practice at CenturyLink, in this SYS-CON.tv interview at 16th Cloud Expo, held June 9-11, 2015, at the Javits Center in New York City.
Jul. 7, 2015 04:15 PM EDT Reads: 803
17th Cloud Expo, taking place Nov 3-5, 2015, at the Santa Clara Convention Center in Santa Clara, CA, will feature technical sessions from a rock star conference faculty and the leading industry players in the world. Cloud computing is now being embraced by a majority of enterprises of all sizes. Yesterday's debate about public vs. private has transformed into the reality of hybrid cloud: a recent survey shows that 74% of enterprises have a hybrid cloud strategy. Meanwhile, 94% of enterprises ar...
Jul. 7, 2015 04:00 PM EDT Reads: 1,977
One of the hottest areas in cloud right now is DRaaS and related offerings. In his session at 16th Cloud Expo, Dale Levesque, Disaster Recovery Product Manager with Windstream's Cloud and Data Center Marketing team, will discuss the benefits of the cloud model, which far outweigh the traditional approach, and how enterprises need to ensure that their needs are properly being met.
Jul. 7, 2015 03:45 PM EDT Reads: 2,423
In the midst of the widespread popularity and adoption of cloud computing, it seems like everything is being offered “as a Service” these days: Infrastructure? Check. Platform? You bet. Software? Absolutely. Toaster? It’s only a matter of time. With service providers positioning vastly differing offerings under a generic “cloud” umbrella, it’s all too easy to get confused about what’s actually being offered. In his session at 16th Cloud Expo, Kevin Hazard, Director of Digital Content for SoftL...
Jul. 7, 2015 03:45 PM EDT Reads: 2,711
"In the IoT space we are helping customers, mostly enterprises and industry verticals where time-to-value is critical, and we help them with the ability to do faster insights and actions using our platform so they can transform their business operations," explained Venkat Eswara, VP of Marketing at Vitria, in this SYS-CON.tv interview at @ThingsExpo, held June 9-11, 2015, at the Javits Center in New York City.
Jul. 7, 2015 03:45 PM EDT Reads: 997
Discussions about cloud computing are evolving into discussions about enterprise IT in general. As enterprises increasingly migrate toward their own unique clouds, new issues such as the use of containers and microservices emerge to keep things interesting. In this Power Panel at 16th Cloud Expo, moderated by Conference Chair Roger Strukhoff, panelists addressed the state of cloud computing today, and what enterprise IT professionals need to know about how the latest topics and trends affect t...
Jul. 7, 2015 03:30 PM EDT Reads: 1,993
Malicious agents are moving faster than the speed of business. Even more worrisome, most companies are relying on legacy approaches to security that are no longer capable of meeting current threats. In the modern cloud, threat diversity is rapidly expanding, necessitating more sophisticated security protocols than those used in the past or in desktop environments. Yet companies are falling for cloud security myths that were truths at one time but have evolved out of existence.
Jul. 7, 2015 03:30 PM EDT Reads: 2,480
[slides] The Secure Path to Value in the Cloud By @Windstream | @CloudExpo #IoT #API #Containers #Microservices
Even as cloud and managed services grow increasingly central to business strategy and performance, challenges remain. The biggest sticking point for companies seeking to capitalize on the cloud is data security. Keeping data safe is an issue in any computing environment, and it has been a focus since the earliest days of the cloud revolution. Understandably so: a lot can go wrong when you allow valuable information to live outside the firewall. Recent revelations about government snooping, along...
Jul. 7, 2015 03:00 PM EDT Reads: 2,397
[slides] Workloads and Public Cloud at @CloudExpo By @utollwi | @ProfitBricksUSA #DevOps #Containers #Microservices
Public Cloud IaaS started its life in the developer and startup communities and has grown rapidly to a $20B+ industry, but it still pales in comparison to how much is spent worldwide on IT: $3.6 trillion. In fact, there are 8.6 million data centers worldwide, the reality is many small and medium sized business have server closets and colocation footprints filled with servers and storage gear. While on-premise environment virtualization may have peaked at 75%, the Public Cloud has lagged in adop...
Jul. 7, 2015 03:00 PM EDT Reads: 2,785
DevOps Summit, taking place Nov 3-5, 2015, at the Santa Clara Convention Center in Santa Clara, CA, is co-located with 17th Cloud Expo and will feature technical sessions from a rock star conference faculty and the leading industry players in the world. The widespread success of cloud computing is driving the DevOps revolution in enterprise IT. Now as never before, development teams must communicate and collaborate in a dynamic, 24/7/365 environment. There is no time to wait for long development...
Jul. 7, 2015 02:45 PM EDT Reads: 2,142
"We have an new division call the Cloud Monetization Division, based on our platform Powua, which empowers enterprises and organizations to take the journey to cloud monetization and to make it a reality," explained Ian Khan, Manager, Innovation & Marketing at Solgenia, in this SYS-CON.tv interview at 16th Cloud Expo, held June 9-11, 2015, at the Javits Center in New York City.
Jul. 7, 2015 02:45 PM EDT Reads: 779
[video] Improving the Developer Experience with @DanKLynn | @CloudExpo #Agile #BigData #IoT #Microservices
"AgilData is the next generation of dbShards. It just adds a whole bunch more functionality to improve the developer experience," noted Dan Lynn, CEO of AgilData, in this SYS-CON.tv interview at 16th Cloud Expo, held June 9-11, 2015, at the Javits Center in New York City.
Jul. 7, 2015 02:30 PM EDT Reads: 1,537
[slides] Extreme Internet of Things Games By @MadGreek65 | @ThingsExpo #IoT #M2M #API #InternetOfThings
To many people, IoT is a buzzword whose value is not understood. Many people think IoT is all about wearables and home automation. In his session at @ThingsExpo, Mike Kavis, Vice President & Principal Cloud Architect at Cloud Technology Partners, discussed some incredible game-changing use cases and how they are transforming industries like agriculture, manufacturing, health care, and smart cities. He will discuss cool technologies like smart dust, robotics, smart labels, and much more. Prepare...
Jul. 7, 2015 02:15 PM EDT Reads: 2,196
In their general session at 16th Cloud Expo, Michael Piccininni, Global Account Manager - Cloud SP at EMC Corporation, and Mike Dietze, Regional Director at Windstream Hosted Solutions, reviewed next generation cloud services, including the Windstream-EMC Tier Storage solutions, and discussed how to increase efficiencies, improve service delivery and enhance corporate cloud solution development. Michael Piccininni is Global Account Manager – Cloud SP at EMC Corporation. He has been engaged in t...
Jul. 7, 2015 02:15 PM EDT Reads: 2,496
SYS-CON Events announced today that MangoApps will exhibit at SYS-CON's 17th International Cloud Expo®, which will take place on November 3–5, 2015, at the Santa Clara Convention Center in Santa Clara, CA. MangoApps provides private all-in-one social intranets allowing workers to securely collaborate from anywhere in the world and from any device. Social, mobile, and easy to use. MangoApps has been named a "Market Leader" by Ovum Research and a "Cool Vendor" by Gartner. 20,000+ business custome...
Jul. 7, 2015 02:00 PM EDT Reads: 2,178
Announcing @AlertLogic “Bronze Sponsor” of @CloudExpo & @DevOpsSummit | #IoT #DevOps #Docker #Microservices
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...
Jul. 7, 2015 01:45 PM EDT Reads: 2,489