Welcome!

Cloud Security Authors: Elizabeth White, Liz McMillan, Pat Romanski, Lisa Calkins, Mamoon Yunus

Related Topics: @CloudExpo, Java IoT, Microservices Expo, Cloud Security, @BigDataExpo, SDN Journal

@CloudExpo: Blog Post

Traffic Advisory: Your Packets May Be Delayed

The past few years have seen a dramatic improvement in the latency in network switches

The past few years have seen a dramatic improvement in the latency in network switches. Single ASIC based switches can all pretty much switch packets in less than a microsecond. Current 10GE switching silicon provides anywhere from 300 to 800 nanoseconds, specialized silicon shaves that to less than 200 nanoseconds when limiting the amount of searching that needs to be done by reducing the size of lookup tables. Even other solutions play some smart tricks by providing forwarding hints for intermediate switches make those lookups take less than 50 nanoseconds.

Notice_Reduce_Speed_When_Entering_Parking_Lot_Signs_T41151-ba

Modular switches inherently have a higher latency. Line cards on modular switches typically have multiple ASICs, those ASICs are connected through a single or multi stage fabric. Each step takes time, resulting in latencies varying from around a microsecond when a packet stays on the same ASIC, to possibly 5-15 microseconds when a packet needs to travel through the fabric and back.

The speediest of ASICs achieve these low numbers by employing cut through switching. Cut through switching allows the ASIC to start transmitting a packet when enough of the header has been received to make a forwarding decision. The ASIC does not wait for the entire packet to be received (the more traditional store-and-forward mechanism), within the first few 100 bytes the forwarding decision has been made, and that same header (modified or not) is being transmitted out the destination port. It's somewhat odd to think that through, but the first bits of a packet may be received by the destination system before the last bits have left the first switch in the network.

Cut through switching comes with quite a few "buts". Most switches can only deploy cut through switching when the source and destination port are the same speed. 10GE in and 40GE out or vice versa is rarely supported and the ASIC will automatically switch to store-and-forward for those packets. For good reason. If a packet comes at you at 40GE rates, you simply cannot transmit it out a 10GE interface, that interface is not fast enough. In the reverse direction speed is not the issue, but if you were to employ cut through switching, for the duration of that packet your 40GE interface effectively runs at 10GE with lots of pauses in between pieces of a packet (figuratively speaking).

In addition, when the destination port has another packet being transmitted or in the queue, a new packet cannot be sent cut through. When another packet is ahead of you, you need to wait. And you may need to wait for quite a while. We often forget that it takes 1.2 microseconds to transmit a 1500 byte packet on a 10GE interface, more than 7 microseconds for a jumbo packet. When the destination port is being paused due to Data Center Bridging Priority Flow Control (PFC), the packet will be queued for store and forward. And make sure you add an extra 3 microseconds for 10GBASE-TX.

Datacenters are on a path to fewer layers of switching. Spine and leaf networks are being pitched as the best performing, low cost solution for dense networks. If you carefully examine the specs and pitches of some of the newer spine switches, you will notice that all of them make a case for deep buffers. Deep buffers assume that this switch needs to manage congestion by buffering packets, why else would you design expensive and power hungry buffer memory into those switches. Buffering and low latency don't go well together. If your spine and leaf network has nothing much to do, you may well see latency numbers of only a few microseconds or better. If the spine layer needs to buffer your packet, this number can jump up quickly to 10s of microseconds. And those large buffers seem to suggest it will.

There certainly are applications that are very sensitive to latency. Financial institution low latency trading networks are the example always used, and there are High Performance Computing environments with database, RDMI or similar applications that benefit from really low latency. Engineering the traffic in such a way that none of the low latency disruptive events described above happen is hard. Really hard. Extremely hard if there is a lot of traffic. Or a lot of endpoints. Networks that are specifically designed to aggregate and distribute (spine and leaf) will be more prone to these latency increasing scenarios. Creating a network with the ability to create isolated direct paths between switches that serve low latency applications is much more likely to avoid these. And even if the absolute latency is not the lowest, consistent latency with little jitter will certainly help the performance of adaptive mechanisms like TCP.

For the vast majority of applications in a typical enterprise datacenter, or a public cloud provider, the difference between 200 nanosecond switch latency and 1 microseconds is not measurably different in terms of user or application performance. The set of applications that behave noticably different at a few microseconds vs 10s of microseconds end to end latency is probably larger. I argue that you will get better results by carefully engineering the traffic for the applications that do care about low latency and low jitter. Make sure they get the bandwidth they need. Make sure they do not clash in the network with data hungry applications. Affinitize your network. It may just give you the latency and jitter performance you need.

The post Traffic advisory: your packets may be delayed 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
IoT is at the core or many Digital Transformation initiatives with the goal of re-inventing a company's business model. We all agree that collecting relevant IoT data will result in massive amounts of data needing to be stored. However, with the rapid development of IoT devices and ongoing business model transformation, we are not able to predict the volume and growth of IoT data. And with the lack of IoT history, traditional methods of IT and infrastructure planning based on the past do not app...
To get the most out of their data, successful companies are not focusing on queries and data lakes, they are actively integrating analytics into their operations with a data-first application development approach. Real-time adjustments to improve revenues, reduce costs, or mitigate risk rely on applications that minimize latency on a variety of data sources. Jack Norris reviews best practices to show how companies develop, deploy, and dynamically update these applications and how this data-first...
Internet-of-Things discussions can end up either going down the consumer gadget rabbit hole or focused on the sort of data logging that industrial manufacturers have been doing forever. However, in fact, companies today are already using IoT data both to optimize their operational technology and to improve the experience of customer interactions in novel ways. In his session at @ThingsExpo, Gordon Haff, Red Hat Technology Evangelist, shared examples from a wide range of industries – including en...
Intelligent Automation is now one of the key business imperatives for CIOs and CISOs impacting all areas of business today. In his session at 21st Cloud Expo, Brian Boeggeman, VP Alliances & Partnerships at Ayehu, will talk about how business value is created and delivered through intelligent automation to today’s enterprises. The open ecosystem platform approach toward Intelligent Automation that Ayehu delivers to the market is core to enabling the creation of the self-driving enterprise.
"We're a cybersecurity firm that specializes in engineering security solutions both at the software and hardware level. Security cannot be an after-the-fact afterthought, which is what it's become," stated Richard Blech, Chief Executive Officer at Secure Channels, in this SYS-CON.tv interview at @ThingsExpo, held November 1-3, 2016, at the Santa Clara Convention Center in Santa Clara, CA.
Consumers increasingly expect their electronic "things" to be connected to smart phones, tablets and the Internet. When that thing happens to be a medical device, the risks and benefits of connectivity must be carefully weighed. Once the decision is made that connecting the device is beneficial, medical device manufacturers must design their products to maintain patient safety and prevent compromised personal health information in the face of cybersecurity threats. In his session at @ThingsExpo...
SYS-CON Events announced today that Grape Up 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. Grape Up is a software company specializing 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 across the U.S. and Europe, Grape Up works with a variety of customers from emergi...
Detecting internal user threats in the Big Data eco-system is challenging and cumbersome. Many organizations monitor internal usage of the Big Data eco-system using a set of alerts. This is not a scalable process given the increase in the number of alerts with the accelerating growth in data volume and user base. Organizations are increasingly leveraging machine learning to monitor only those data elements that are sensitive and critical, autonomously establish monitoring policies, and to detect...
SYS-CON Events announced today that Massive Networks 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. Massive Networks mission is simple. To help your business operate seamlessly with fast, reliable, and secure internet and network solutions. Improve your customer's experience with outstanding connections to your cloud.
Everything run by electricity will eventually be connected to the Internet. Get ahead of the Internet of Things revolution and join Akvelon expert and IoT industry leader, Sergey Grebnov, in his session at @ThingsExpo, for an educational dive into the world of managing your home, workplace and all the devices they contain with the power of machine-based AI and intelligent Bot services for a completely streamlined experience.
Because IoT devices are deployed in mission-critical environments more than ever before, it’s increasingly imperative they be truly smart. IoT sensors simply stockpiling data isn’t useful. IoT must be artificially and naturally intelligent in order to provide more value In his session at @ThingsExpo, John Crupi, Vice President and Engineering System Architect at Greenwave Systems, will discuss how IoT artificial intelligence (AI) can be carried out via edge analytics and machine learning techn...
With tough new regulations coming to Europe on data privacy in May 2018, Calligo will explain why in reality the effect is global and transforms how you consider critical data. EU GDPR fundamentally rewrites the rules for cloud, Big Data and IoT. In his session at 21st Cloud Expo, Adam Ryan, Vice President and General Manager EMEA at Calligo, will examine the regulations and provide insight on how it affects technology, challenges the established rules and will usher in new levels of diligence a...
In the enterprise today, connected IoT devices are everywhere – both inside and outside corporate environments. The need to identify, manage, control and secure a quickly growing web of connections and outside devices is making the already challenging task of security even more important, and onerous. In his session at @ThingsExpo, Rich Boyer, CISO and Chief Architect for Security at NTT i3, discussed new ways of thinking and the approaches needed to address the emerging challenges of security i...
SYS-CON Events announced today that Datera, that offers a radically new data management architecture, 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. Datera is transforming the traditional datacenter model through modern cloud simplicity. The technology industry is at another major inflection point. The rise of mobile, the Internet of Things, data storage and Big...
An increasing number of companies are creating products that combine data with analytical capabilities. Running interactive queries on Big Data requires complex architectures to store and query data effectively, typically involving data streams, an choosing efficient file format/database and multiple independent systems that are tied together through custom-engineered pipelines. In his session at @BigDataExpo at @ThingsExpo, Tomer Levi, a senior software engineer at Intel’s Advanced Analytics ...
SYS-CON Events announced today that Datera 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. Datera offers a radically new approach to data management, where innovative software makes data infrastructure invisible, elastic and able to perform at the highest level. It eliminates hardware lock-in and gives IT organizations the choice to source x86 server nodes, with business model option...
With 10 simultaneous tracks, keynotes, general sessions and targeted breakout classes, Cloud Expo and @ThingsExpo are two of the most important technology events of the year. Since its launch over eight years ago, Cloud Expo and @ThingsExpo have presented a rock star faculty as well as showcased hundreds of sponsors and exhibitors! In this blog post, I provide 7 tips on how, as part of our world-class faculty, you can deliver one of the most popular sessions at our events. But before reading the...
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...
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...
In his session at 21st Cloud Expo, Carl J. Levine, Senior Technical Evangelist for NS1, will objectively discuss how DNS is used to solve Digital Transformation challenges in large SaaS applications, CDNs, AdTech platforms, and other demanding use cases. Carl J. Levine is the Senior Technical Evangelist for NS1. A veteran of the Internet Infrastructure space, he has over a decade of experience with startups, networking protocols and Internet infrastructure, combined with the unique ability to it...