Welcome!

Containers Expo Blog Authors: Elizabeth White, Mehdi Daoudi, Ravi Rajamiyer, Pat Romanski, Amit Gupta

Blog Feed Post

It's On: Stacks versus Flows

#OpenStack #CloudStack #OpenFlow #SDN It's a showdown of model versus control – or is it?

 

stack-vs-flow

There's a lot of noise about "wars" in the networking world these days. OpenStack versus CloudStack versus OpenFlow-based SDN.

But while there are definitely aspects of "stacks" that share similarities with "flows", they are not the same model and ultimately they aren't even necessarily attempting to solve the same problems.

Understanding the two models and what they're intended to do can go a long way toward resolving any perceived conflicts.

The Stack Model

Stack models, such as CloudStack and OpenStack, are more accurately placed in the category of "cloud management frameworks" because they are designed with provisioning and management of the infrastructure services that comprise a cloud computing (or highly dynamic) environment.

Stacks are aptly named as they attempt to provide management and specifically automation of provisioning for the complete network stack. Both CloudStack and OpenStack, along with Eucalyptus and Amazon and VMware vCloud, provide a framework API that can (ostensibly) be used to provision infrastructure services irrespective of vendor implementation. The vision is (or should be) to enable implementers (whether service provider or enterprise) to be able to switch out architectural elements (routers, switches, hypervisors, load balancers, etc… ) transparently*. That is, moving from Dell to HP to Cisco (or vice-versa) as an environment's switching fabric should not be disruptive. Physical changes should be able to occur without impacting the provisioning and management of the actual services provided by the infrastructure.

And yes, such a strategy should also allow heterogeneity of infrastructure.

In many ways, such "stacks" are the virtualization of the data center, enabling abstraction of the actual implementation from the configuration and automation of the hardware (or software) elements. This, more than anything, is what enables a comparison with flow-based models.

The Flow Model

Flow-based models, in particular OpenFlow-based SDN, also abstracts implementation from configuration by decoupling the control plane from the data plane. This allows any OpenFlow-enabled device (mostly switches today, as SDN and OpenFlow focus on network layers) to be configured and managed via a centralized controller using a common API.

Flows are "installed" or "inserted" into OpenFlow-enabled elements via OpenFlow, an open protocol designed for this purpose, and support real-time updates that enable on-demand optimization or fault isolation of flows through the network. OpenFlow and SDN are focused on managing the flow of traffic through a network. 

Flow-based models purport to offer the same benefits as a stack model in terms of heterogeneity and interoperability. Moving from one OpenFlow-enabled switch to another (or mixing and matching) should ostensibly have no impact on the network whatsoever.

What flow-based models offer above and beyond a stack model is extensibility. OpenFlow-based SDN models using a centralized controller also carry with it the premise of being able to programmatically add new services to the network without vendor assistance. "Applications" deployed on an SDN controller platform (for lack of a better term) can extend existing services or add new ones and there is no need to change anything in the network fabric, because ultimately every "application" distills flows into a simple forwarding decision that can then be applied like a pattern to future flows by the switches.

The Differences

This is markedly different from the focus of a stack, which is on provisioning and management, even though both may be occurring in real-time. While it's certainly the case that through the CloudStack API you can create or delete port forwarding rules on a firewall, these actions are pushed (initiated) external to the firewall. It is not the case that the firewall receives a packet and asks the cloud framework for the appropriate action, which is the model in play for a switch in an OpenFlow-based SDN.

Another (relatively unmentioned but important) distinction is who bears responsibility for integration. A stack-based model puts the onus on the stack to integrate (via what are usually called "plug-ins" or "drivers") with the component's existing API (assuming one exists). A flow-based model requires the vendor to take responsibility for enabling OpenFlow support natively. Obviously the ecosystem of available resources to perform integration is a magnitude higher with a stack model than with a flow model. While vendors are involved in development of drivers/plug-ins for stacks now, the impact on the product itself is minimal, if any at all, because the integration occurs external to the component. Enabling native OpenFlow support on components requires a lot more internal resources be directed at such a project.

Do these differences make for an either-or choice?

Actually, they don't. The models are not mutually exclusive and, in fact, might be used in conjunction with one another quite well. A stack based approach to provisioning and management might well be complemented by an OpenFlow SDN in which flows through the network can be updated in real time or, as is often proffered as a possibility, the deployment of new protocols or services within the network.

The War that Isn't

While there certainly may be a war raging amongst the various stack models, it doesn't appear that a war between OpenFlow and *-Stack is something that's real or ever will be The two foci are very different, and realistically the two could easily be deployed in the same network and solve multiple problems. Network resources may be provisioned and initially configured via a stack but updated in real-time or extended by an SDN controller, assuming such network resources were OpenFlow-enabled in the first place.

 

* That's the vision (and the way it should be) at least. Reality thus far is that the OpenStack API doesn't support most network elements above L3 yet, and CloudStack is tightly coupling API calls to components, rendering this alleged benefit well, not a benefit at all, at least at L4 and above. 


Read the original blog entry...

More Stories By Lori MacVittie

Lori MacVittie is responsible for education and evangelism of application services available across F5’s entire product suite. Her role includes authorship of technical materials and participation in a number of community-based forums and industry standards organizations, among other efforts. MacVittie has extensive programming experience as an application architect, as well as network and systems development and administration expertise. Prior to joining F5, MacVittie was an award-winning Senior Technology Editor at Network Computing Magazine, where she conducted product research and evaluation focused on integration with application and network architectures, and authored articles on a variety of topics aimed at IT professionals. Her most recent area of focus included SOA-related products and architectures. She holds a B.S. in Information and Computing Science from the University of Wisconsin at Green Bay, and an M.S. in Computer Science from Nova Southeastern University.

@ThingsExpo Stories
SYS-CON Events announced today that Daiya Industry will exhibit at the Japan External Trade Organization (JETRO) Pavilion at SYS-CON's 21st International Cloud Expo®, which will take place on Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. Daiya Industry specializes in orthotic support systems and assistive devices with pneumatic artificial muscles in order to contribute to an extended healthy life expectancy. For more information, please visit https://www.daiyak...
SYS-CON Events announced today that Nihon Micron will exhibit at the Japan External Trade Organization (JETRO) Pavilion at SYS-CON's 21st International Cloud Expo®, which will take place on Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. Nihon Micron Co., Ltd. strives for technological innovation to establish high-density, high-precision processing technology for providing printed circuit board and metal mount RFID tags used for communication devices. For more inf...
SYS-CON Events announced today that Massive Networks, that helps your business operate seamlessly with fast, reliable, and secure internet and network solutions, has been named "Exhibitor" of SYS-CON's 21st International Cloud Expo ®, which will take place on Oct 31 - Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. As a premier telecommunications provider, Massive Networks is headquartered out of Louisville, Colorado. With years of experience under their belt, their team of...
SYS-CON Events announced today that Suzuki Inc. will exhibit at the Japan External Trade Organization (JETRO) Pavilion at SYS-CON's 21st International Cloud Expo®, which will take place on Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. Suzuki Inc. is a semiconductor-related business, including sales of consuming parts, parts repair, and maintenance for semiconductor manufacturing machines, etc. It is also a health care business providing experimental research for...
SYS-CON Events announced today that mruby Forum will exhibit at the Japan External Trade Organization (JETRO) Pavilion at SYS-CON's 21st International Cloud Expo®, which will take place on Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. mruby is the lightweight implementation of the Ruby language. We introduce mruby and the mruby IoT framework that enhances development productivity. For more information, visit http://forum.mruby.org/.
Elon Musk is among the notable industry figures who worries about the power of AI to destroy rather than help society. Mark Zuckerberg, on the other hand, embraces all that is going on. AI is most powerful when deployed across the vast networks being built for Internets of Things in the manufacturing, transportation and logistics, retail, healthcare, government and other sectors. Is AI transforming IoT for the good or the bad? Do we need to worry about its potential destructive power? Or will we...
In his session at @ThingsExpo, Greg Gorman is the Director, IoT Developer Ecosystem, Watson IoT, will provide a short tutorial on Node-RED, a Node.js-based programming tool for wiring together hardware devices, APIs and online services in new and interesting ways. It provides a browser-based editor that makes it easy to wire together flows using a wide range of nodes in the palette that can be deployed to its runtime in a single-click. There is a large library of contributed nodes that help so...
SYS-CON Events announced today that B2Cloud will exhibit at SYS-CON's 21st International Cloud Expo®, which will take place on Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. B2Cloud specializes in IoT devices for preventive and predictive maintenance in any kind of equipment retrieving data like Energy consumption, working time, temperature, humidity, pressure, etc.
What is the best strategy for selecting the right offshore company for your business? In his session at 21st Cloud Expo, Alan Winters, U.S. Head of Business Development at MobiDev, will discuss the things to look for - positive and negative - in evaluating your options. He will also discuss how to maximize productivity with your offshore developers. Before you start your search, clearly understand your business needs and how that impacts software choices.
SYS-CON Events announced today that NetApp has been named “Bronze Sponsor” of SYS-CON's 21st International Cloud Expo®, which will take place on Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. NetApp is the data authority for hybrid cloud. NetApp provides a full range of hybrid cloud data services that simplify management of applications and data across cloud and on-premises environments to accelerate digital transformation. Together with their partners, NetApp em...
SYS-CON Events announced today that SIGMA Corporation will exhibit at the Japan External Trade Organization (JETRO) Pavilion at SYS-CON's 21st International Cloud Expo®, which will take place on Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. uLaser flow inspection device from the Japanese top share to Global Standard! Then, make the best use of data to flip to next page. For more information, visit http://www.sigma-k.co.jp/en/.
Agile has finally jumped the technology shark, expanding outside the software world. Enterprises are now increasingly adopting Agile practices across their organizations in order to successfully navigate the disruptive waters that threaten to drown them. In our quest for establishing change as a core competency in our organizations, this business-centric notion of Agile is an essential component of Agile Digital Transformation. In the years since the publication of the Agile Manifesto, the conn...
Real IoT production deployments running at scale are collecting sensor data from hundreds / thousands / millions of devices. The goal is to take business-critical actions on the real-time data and find insights from stored datasets. In his session at @ThingsExpo, John Walicki, Watson IoT Developer Advocate at IBM Cloud, will provide a fast-paced developer journey that follows the IoT sensor data from generation, to edge gateway, to edge analytics, to encryption, to the IBM Bluemix cloud, to Wa...
SYS-CON Events announced today that MIRAI Inc. will exhibit at the Japan External Trade Organization (JETRO) Pavilion at SYS-CON's 21st International Cloud Expo®, which will take place on Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. MIRAI Inc. are IT consultants from the public sector whose mission is to solve social issues by technology and innovation and to create a meaningful future for people.
There is huge complexity in implementing a successful digital business that requires efficient on-premise and cloud back-end infrastructure, IT and Internet of Things (IoT) data, analytics, Machine Learning, Artificial Intelligence (AI) and Digital Applications. In the data center alone, there are physical and virtual infrastructures, multiple operating systems, multiple applications and new and emerging business and technological paradigms such as cloud computing and XaaS. And then there are pe...
SYS-CON Events announced today that Keisoku Research Consultant Co. will exhibit at the Japan External Trade Organization (JETRO) Pavilion at SYS-CON's 21st International Cloud Expo®, which will take place on Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. Keisoku Research Consultant, Co. offers research and consulting in a wide range of civil engineering-related fields from information construction to preservation of cultural properties. For more information, vi...
While some developers care passionately about how data centers and clouds are architected, for most, it is only the end result that matters. To the majority of companies, technology exists to solve a business problem, and only delivers value when it is solving that problem. 2017 brings the mainstream adoption of containers for production workloads. In his session at 21st Cloud Expo, Ben McCormack, VP of Operations at Evernote, will discuss how data centers of the future will be managed, how th...
SYS-CON Events announced today that Fusic will exhibit at the Japan External Trade Organization (JETRO) Pavilion at SYS-CON's 21st International Cloud Expo®, which will take place on Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. Fusic Co. provides mocks as virtual IoT devices. You can customize mocks, and get any amount of data at any time in your test. For more information, visit https://fusic.co.jp/english/.
SYS-CON Events announced today that Enroute Lab will exhibit at the Japan External Trade Organization (JETRO) Pavilion at SYS-CON's 21st International Cloud Expo®, which will take place on Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. Enroute Lab is an industrial design, research and development company of unmanned robotic vehicle system. For more information, please visit http://elab.co.jp/.
SYS-CON Events announced today that Mobile Create USA will exhibit at the Japan External Trade Organization (JETRO) Pavilion at SYS-CON's 21st International Cloud Expo®, which will take place on Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. Mobile Create USA Inc. is an MVNO-based business model that uses portable communication devices and cellular-based infrastructure in the development, sales, operation and mobile communications systems incorporating GPS capabi...