Welcome!

Containers Expo Blog Authors: Mehdi Daoudi, Elizabeth White, John Rauser, Pat Romanski, Liz McMillan

Related Topics: Containers Expo Blog, Microservices Expo, @CloudExpo, Cloud Security, @BigDataExpo, SDN Journal

Containers Expo Blog: Blog Post

Red Sox, Pumpkins and Packet Encapsulation

Network virtualization allows the amount of attached VLANs & networks to scale beyond what a single physical switch can handle

[This is not really about the Red Sox or pumpkins this Halloween, but how could I not use those in the title? Go Red Sox]

I left an awful teaser at the end of my article last week. In Brent Salisbury's original article that triggered some of these additional virtualization thoughts, he articulated two very clear differences between native network based L2 virtualization mechanisms and the mechanisms that are being provided by overlay solutions based mostly in server vSwitch infrastructure. These two fundamental functions are MAC learning and tunnel encapsulation. In today's post I will spend a little more time looking at encapsulation differences.

redsox pumpkinOutside of logical separation of multiple virtual networks or tenants, network virtualization allows the amount of attached VLANs, networks and devices to scale well beyond what a single physical switch can handle. In a traditional network, an edge switch will only maintain tables for its local VLANs, ports and learned MAC addresses, but core switches that connect these edge switches together will have to maintain the union of all these edge tables, limiting the size of the network, or forcing extremely large (read expensive) core switches that can cope.  In a virtualized network, a VLAN is no longer a unique identifier. The same VLAN can appear many times on different ports in the network, all mapped to different virtual networks or tenants.

To achieve this scaling and re-use of VLAN space, original user traffic has a new header added to it, effectively hiding the original VLAN, source and destination MAC address. Traffic is exchanged between edge switches that serve the specific members of this virtual network, passing through the core of the network based on the new header alone. Using this re-encapsulation creates a tunnel and intermediate switches are oblivious to the original packet, allowing them to scale by having to know only how to locate the edge switches.

Traditional L2 virtualization mechanisms use an extra L2 header for the tunnel, most commonly a MAC-in-MAC encapsulation. This encapsulation adds a new ethernet header onto the original packet, with the source edge switch as the source MAC, the destination edge switch as the destination MAC, and some other fields including an identifier for the virtual network. Switches in the core must only provide end to end ethernet service to the edge switches, since all they see are these newly ethernet encapsulated packets. Their tables stay sparsely populated, since the edge switch MAC addresses and the VLANs used for transport are the only bits needed for packet forwarding.

And this is where overlay solutions have taken a step forward. Whether its VXLAN, NVGRE or STT, all proposed/used overlay encapsulation mechanisms wrap the original packet into an IP packet. The tunnel between the edge switches is an IP/UDP connection (except for STT which "uses" TCP, but really doesn't), and transport requires regular IP connectivity between them. Now, this certainly increases the size of an original packet by quite a bit, the edge switch adds a UDP header, an IP header and then (assuming its still transported across an ethernet network) an ethernet header, but it creates an abstraction and a degree of freedom between the edge devices, and the transport network that connects them.

There is nothing wrong with ethernet based encapsulations for a virtualized network. I have seen them work, I have seen them work well. But when the virtualization edge becomes the vSwitch in a server, the sheer amount of edge switches (vSwitch in this case) that need to be connected together using a single or small number of transport VLANs in an ethernet core may start to run into the scaling concerns for a single broadcast domain discussed last week. When it is hundreds of edge devices some of the SPB or TRILL based solutions may become challenged, I bet you almost all of them will when you start talking thousands of edge devices.

Besides the obvious ability to create tunnels between remote but IP connected virtual network islands, having tunnels based on IP is actually an added convenience, even if the network based virtualization solution can be created on top of a single VLAN ethernet network. An extra set of headers provide additional tables, additional lookup opportunities in hardware to send traffic where you want it to be sent. Not the ECMP way, but in a controlled and carefully calculated way in order to satisfy the needs of the virtual network. And that makes VXLAN equally suited as a pure physical network based virtualization transport mechanism even if there is no overlay.

Rather than leaving a poor hint of what to expect, next week I will discuss the second major difference from Bren't original article: MAC learning in a virtualized network and the role of a controller in determining virtual network membership and location.

Happy Halloween!

[Today's fun fact: Lego produces more rubber tires than any other tire company in the world (381 million in 2011)]

The post Red Sox, Pumpkins and Packet Encapsulation appeared first on Plexxi.

Read the original blog entry...

More Stories By Marten Terpstra

Marten Terpstra is a Product Management Director at Plexxi Inc. Marten has extensive knowledge of the architecture, design, deployment and management of enterprise and carrier networks.

@ThingsExpo Stories
SYS-CON Events announced today that CA Technologies has been named "Platinum Sponsor" of SYS-CON's 21st International Cloud Expo®, which will take place October 31-November 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. CA Technologies helps customers succeed in a future where every business - from apparel to energy - is being rewritten by software. From planning to development to management to security, CA creates software that fuels transformation for companies in the applic...
SYS-CON Events announced today that IBM has been named “Diamond Sponsor” of SYS-CON's 21st Cloud Expo, which will take place on October 31 through November 2nd 2017 at the Santa Clara Convention Center in Santa Clara, California.
In his session at Cloud Expo, Alan Winters, an entertainment executive/TV producer turned serial entrepreneur, presented a success story of an entrepreneur who has both suffered through and benefited from offshore development across multiple businesses: The smart choice, or how to select the right offshore development partner Warning signs, or how to minimize chances of making the wrong choice Collaboration, or how to establish the most effective work processes Budget control, or how to ma...
SYS-CON Events announced today that Cloud Academy named "Bronze Sponsor" of 21st International Cloud Expo which will take place October 31 - November 2, 2017 at the Santa Clara Convention Center in Santa Clara, CA. Cloud Academy is the industry’s most innovative, vendor-neutral cloud technology training platform. Cloud Academy provides continuous learning solutions for individuals and enterprise teams for Amazon Web Services, Microsoft Azure, Google Cloud Platform, and the most popular cloud com...
With major technology companies and startups seriously embracing Cloud strategies, now is the perfect time to attend 21st Cloud Expo October 31 - November 2, 2017, at the Santa Clara Convention Center, CA, and June 12-14, 2018, at the Javits Center in New York City, NY, and learn what is going on, contribute to the discussions, and ensure that your enterprise is on the right path to Digital Transformation.
We build IoT infrastructure products - when you have to integrate different devices, different systems and cloud you have to build an application to do that but we eliminate the need to build an application. Our products can integrate any device, any system, any cloud regardless of protocol," explained Peter Jung, Chief Product Officer at Pulzze Systems, in this SYS-CON.tv interview at @ThingsExpo, held November 1-3, 2016, at the Santa Clara Convention Center in Santa Clara, CA
"When we talk about cloud without compromise what we're talking about is that when people think about 'I need the flexibility of the cloud' - it's the ability to create applications and run them in a cloud environment that's far more flexible,” explained Matthew Finnie, CTO of Interoute, in this SYS-CON.tv interview at 20th Cloud Expo, held June 6-8, 2017, at the Javits Center in New York City, NY.
In his session at @ThingsExpo, Eric Lachapelle, CEO of the Professional Evaluation and Certification Board (PECB), provided an overview of various initiatives to certify the security of connected devices and future trends in ensuring public trust of IoT. Eric Lachapelle is the Chief Executive Officer of the Professional Evaluation and Certification Board (PECB), an international certification body. His role is to help companies and individuals to achieve professional, accredited and worldwide re...
Amazon started as an online bookseller 20 years ago. Since then, it has evolved into a technology juggernaut that has disrupted multiple markets and industries and touches many aspects of our lives. It is a relentless technology and business model innovator driving disruption throughout numerous ecosystems. Amazon’s AWS revenues alone are approaching $16B a year making it one of the largest IT companies in the world. With dominant offerings in Cloud, IoT, eCommerce, Big Data, AI, Digital Assista...
When growing capacity and power in the data center, the architectural trade-offs between server scale-up vs. scale-out continue to be debated. Both approaches are valid: scale-out adds multiple, smaller servers running in a distributed computing model, while scale-up adds fewer, more powerful servers that are capable of running larger workloads. It’s worth noting that there are additional, unique advantages that scale-up architectures offer. One big advantage is large memory and compute capacity...
Internet of @ThingsExpo, taking place October 31 - November 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA, is co-located with 21st Cloud Expo and will feature technical sessions from a rock star conference faculty and the leading industry players in the world. The Internet of Things (IoT) is the most profound change in personal and enterprise IT since the creation of the Worldwide Web more than 20 years ago. All major researchers estimate there will be tens of billions devic...
IoT solutions exploit operational data generated by Internet-connected smart “things” for the purpose of gaining operational insight and producing “better outcomes” (for example, create new business models, eliminate unscheduled maintenance, etc.). The explosive proliferation of IoT solutions will result in an exponential growth in the volume of IoT data, precipitating significant Information Governance issues: who owns the IoT data, what are the rights/duties of IoT solutions adopters towards t...
With the introduction of IoT and Smart Living in every aspect of our lives, one question has become relevant: What are the security implications? To answer this, first we have to look and explore the security models of the technologies that IoT is founded upon. In his session at @ThingsExpo, Nevi Kaja, a Research Engineer at Ford Motor Company, discussed some of the security challenges of the IoT infrastructure and related how these aspects impact Smart Living. The material was delivered interac...
No hype cycles or predictions of zillions of things here. IoT is big. You get it. You know your business and have great ideas for a business transformation strategy. What comes next? Time to make it happen. In his session at @ThingsExpo, Jay Mason, Associate Partner at M&S Consulting, presented a step-by-step plan to develop your technology implementation strategy. He discussed the evaluation of communication standards and IoT messaging protocols, data analytics considerations, edge-to-cloud tec...
The Internet giants are fully embracing AI. All the services they offer to their customers are aimed at drawing a map of the world with the data they get. The AIs from these companies are used to build disruptive approaches that cannot be used by established enterprises, which are threatened by these disruptions. However, most leaders underestimate the effect this will have on their businesses. In his session at 21st Cloud Expo, Rene Buest, Director Market Research & Technology Evangelism at Ara...
Artificial intelligence, machine learning, neural networks. We’re in the midst of a wave of excitement around AI such as hasn’t been seen for a few decades. But those previous periods of inflated expectations led to troughs of disappointment. Will this time be different? Most likely. Applications of AI such as predictive analytics are already decreasing costs and improving reliability of industrial machinery. Furthermore, the funding and research going into AI now comes from a wide range of com...
SYS-CON Events announced today that Enzu will exhibit at SYS-CON's 21st Int\ernational Cloud Expo®, which will take place October 31-November 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. Enzu’s mission is to be the leading provider of enterprise cloud solutions worldwide. Enzu enables online businesses to use its IT infrastructure to their competitive advantage. By offering a suite of proven hosting and management services, Enzu wants companies to focus on the core of their ...
SYS-CON Events announced today that MobiDev, a client-oriented software development company, will exhibit at SYS-CON's 21st International Cloud Expo®, which will take place October 31-November 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. MobiDev is a software company that develops and delivers turn-key mobile apps, websites, web services, and complex software systems for startups and enterprises. Since 2009 it has grown from a small group of passionate engineers and business...
SYS-CON Events announced today that GrapeUp, the leading provider of rapid product development at the speed of business, will exhibit at SYS-CON's 21st International Cloud Expo®, which will take place October 31-November 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. Grape Up is a software company, specialized in cloud native application development and professional services related to Cloud Foundry PaaS. With five expert teams that operate in various sectors of the market acr...
SYS-CON Events announced today that Ayehu will exhibit at SYS-CON's 21st International Cloud Expo®, which will take place on October 31 - November 2, 2017 at the Santa Clara Convention Center in Santa Clara California. Ayehu provides IT Process Automation & Orchestration solutions for IT and Security professionals to identify and resolve critical incidents and enable rapid containment, eradication, and recovery from cyber security breaches. Ayehu provides customers greater control over IT infras...