Welcome!

Containers Expo Blog Authors: AppDynamics Blog, Christopher Keene, Liz McMillan, David Paquette, Craig Lowell

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

SDN Journal: Blog Post

Aggregation Is Good. Aggregation Is Bad.

The vast majority of networking equipment is driven by specialized hardware

For as long as I remember networking has struggled with the balance between aggregated and individual traffic flows. Following the abilities of the technology components we use, we have been forced to aggregate, only to be allowed to de-aggregate or skip aggregation when technology caught up or surpassed the needs of today.

The vast majority of networking equipment is driven by specialized hardware. For datacenter switches, speed and port density are driving the requirements and physics and our technology capabilities create trade-offs that ultimately lead to some form of aggregation. Higher speed and more ports are traded off against memory, table space and functionality. These trade-offs will always exist, no matter what we are trying to build. Networking based in servers will have oodles of memory and table space to do very specific things for many many flows, making it extremely flexible, but those same servers cannot touch the packet processing speeds of the specialized packet processing hardware from Broadcom, Intel or Marvell, or the custom ASICs from Cisco, Juniper, or most anyone else.

funnelSo like it or not, we will want to do more than our hardware is capable of and as a result, we create aggregation points in the network where we lump a bunch of flows together into an aggregate flow and start making decisions on those. Nothing new, even good ole IP forwarding is doing so on an aggregate set of flows, it only makes decisions for all flows destined to a specific IP address.

Network tunnels are the most obvious examples of aggregation, their purpose is to hide information from intermediate networking equipment. In some cases we hide it to keep our table sizes under control, in some cases we hide it because we do not want the intermediate equipment to be able to see what we are transporting (IPSec, SSL, etc). And while sometimes the intermediate systems can see everything that is there, managing the complexity of that visibility simply becomes too expensive. This is why networks that are entirely managed and controlled per flow do not really exist at any reasonable scale, and probably never will.

For the exact same reason we aggregate, we lose the ability to act on specifics. When our tables are not large enough to track each and every flow, we can only make decisions based on what we have decided to keep in common. When talking about tunnels, the tunnel endpoints put new headers onto the original packets and intermediate systems can only act (with minor exceptions) on the information provided in these new headers. The original detail is still there and often visible to the intermediate system, but the intermediate system does not have the capacity to act on the sheer volume of that detail.

And there is the struggle. If I have more information, I can make better decisions. But when I aggregate because I cannot handle that extra information (due to sheer size or management complexity), my decisions by definition become more coarse and as a result, less accurate. But we want it all. We want the power to make decisions based on the most specific information we can, but want to aggregate for operational simplicity or because our hardware dictates. And this is where we get creative and start to turn what used to be black and white into gray.

There is nothing wrong with attempting to act on specifics for aggregate flows, but in so many cases its done as an afterthought and becomes hard to manage, control or specify. Some of the techniques we use are fairly clean, like taking the DSCP values from a packet and replicating it in the outer header of that same packet in a tunnel. Others are far more obscure like calculating some hash function on a packet header and using it as the UDP source port for the VXLAN encapsulated version of that packet. In even others, the original internals may be completely invisible to intermediate systems. STT for instance re-uses the format of TCP packets for its own purpose, but as a side effect of using it as a streaming-like protocol is that the original packet headers may not actually be in an IP packet on the wire. The STT header provides for a 64 bit Context-ID that can be used to take some bits of information from the original packet, but that STT header only appears in the first of what could be many individual packets that are re-assembled in the receiving NIC. Over the Christmas break I spent some time looking at each of the overlay formats and the tools modern day packet processors give you to act on these headers. I will share some of this in this forum next week.

Ultimately, overlay networks are creating a renewed emphasis on the choices between aggregation and individuality. Designed specifically to allow for more complex and scaled networks that hide a lot of the details from the dedicated network hardware, it comes with the price of less granular decisions by that hardware, which can certainly lead to less than optimal use of the available network.

[Today's fun fact: In the Netherlands, there is a 40% higher chance of homeowner insurance claims on the home owner's birthday. Those are some good parties.]

The post Aggregation is Good. Aggregation is Bad. 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
Today we can collect lots and lots of performance data. We build beautiful dashboards and even have fancy query languages to access and transform the data. Still performance data is a secret language only a couple of people understand. The more business becomes digital the more stakeholders are interested in this data including how it relates to business. Some of these people have never used a monitoring tool before. They have a question on their mind like “How is my application doing” but no id...
Identity is in everything and customers are looking to their providers to ensure the security of their identities, transactions and data. With the increased reliance on cloud-based services, service providers must build security and trust into their offerings, adding value to customers and improving the user experience. Making identity, security and privacy easy for customers provides a unique advantage over the competition.
Is the ongoing quest for agility in the data center forcing you to evaluate how to be a part of infrastructure automation efforts? As organizations evolve toward bimodal IT operations, they are embracing new service delivery models and leveraging virtualization to increase infrastructure agility. Therefore, the network must evolve in parallel to become equally agile. Read this essential piece of Gartner research for recommendations on achieving greater agility.
Smart Cities are here to stay, but for their promise to be delivered, the data they produce must not be put in new siloes. In his session at @ThingsExpo, Mathias Herberts, Co-founder and CTO of Cityzen Data, will deep dive into best practices that will ensure a successful smart city journey.
DevOps at Cloud Expo, taking place Nov 1-3, 2016, at the Santa Clara Convention Center in Santa Clara, CA, is co-located with 19th 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 dev...
Internet of @ThingsExpo, taking place November 1-3, 2016, at the Santa Clara Convention Center in Santa Clara, CA, is co-located with 19th 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 devices - comp...
The 19th International Cloud Expo has announced that its Call for Papers is open. Cloud Expo, to be held November 1-3, 2016, at the Santa Clara Convention Center in Santa Clara, CA, brings together Cloud Computing, Big Data, Internet of Things, DevOps, Digital Transformation, Microservices and WebRTC to one location. With cloud computing driving a higher percentage of enterprise IT budgets every year, it becomes increasingly important to plant your flag in this fast-expanding business opportuni...
SYS-CON Events announced today that Venafi, the Immune System for the Internet™ and the leading provider of Next Generation Trust Protection, will exhibit at @DevOpsSummit at 19th International Cloud Expo, which will take place on November 1–3, 2016, at the Santa Clara Convention Center in Santa Clara, CA. Venafi is the Immune System for the Internet™ that protects the foundation of all cybersecurity – cryptographic keys and digital certificates – so they can’t be misused by bad guys in attacks...
SYS-CON Events announced today Telecom Reseller has been named “Media Sponsor” of SYS-CON's 19th International Cloud Expo, which will take place on November 1–3, 2016, at the Santa Clara Convention Center in Santa Clara, CA. Telecom Reseller reports on Unified Communications, UCaaS, BPaaS for enterprise and SMBs. They report extensively on both customer premises based solutions such as IP-PBX as well as cloud based and hosted platforms.
For basic one-to-one voice or video calling solutions, WebRTC has proven to be a very powerful technology. Although WebRTC’s core functionality is to provide secure, real-time p2p media streaming, leveraging native platform features and server-side components brings up new communication capabilities for web and native mobile applications, allowing for advanced multi-user use cases such as video broadcasting, conferencing, and media recording.
Data is the fuel that drives the machine learning algorithmic engines and ultimately provides the business value. In his session at Cloud Expo, Ed Featherston, a director and senior enterprise architect at Collaborative Consulting, will discuss the key considerations around quality, volume, timeliness, and pedigree that must be dealt with in order to properly fuel that engine.
Pulzze Systems was happy to participate in such a premier event and thankful to be receiving the winning investment and global network support from G-Startup Worldwide. It is an exciting time for Pulzze to showcase the effectiveness of innovative technologies and enable them to make the world smarter and better. The reputable contest is held to identify promising startups around the globe that are assured to change the world through their innovative products and disruptive technologies. There w...
Akana has announced the availability of version 8 of its API Management solution. The Akana Platform provides an end-to-end API Management solution for designing, implementing, securing, managing, monitoring, and publishing APIs. It is available as a SaaS platform, on-premises, and as a hybrid deployment. Version 8 introduces a lot of new functionality, all aimed at offering customers the richest API Management capabilities in a way that is easier than ever for API and app developers to use.
Personalization has long been the holy grail of marketing. Simply stated, communicate the most relevant offer to the right person and you will increase sales. To achieve this, you must understand the individual. Consequently, digital marketers developed many ways to gather and leverage customer information to deliver targeted experiences. In his session at @ThingsExpo, Lou Casal, Founder and Principal Consultant at Practicala, discussed how the Internet of Things (IoT) has accelerated our abil...
SYS-CON Events announced today that 910Telecom will exhibit at the 19th International Cloud Expo, which will take place on November 1–3, 2016, at the Santa Clara Convention Center in Santa Clara, CA. Housed in the classic Denver Gas & Electric Building, 910 15th St., 910Telecom is a carrier-neutral telecom hotel located in the heart of Denver. Adjacent to CenturyLink, AT&T, and Denver Main, 910Telecom offers connectivity to all major carriers, Internet service providers, Internet backbones and ...
With so much going on in this space you could be forgiven for thinking you were always working with yesterday’s technologies. So much change, so quickly. What do you do if you have to build a solution from the ground up that is expected to live in the field for at least 5-10 years? This is the challenge we faced when we looked to refresh our existing 10-year-old custom hardware stack to measure the fullness of trash cans and compactors.
The emerging Internet of Everything creates tremendous new opportunities for customer engagement and business model innovation. However, enterprises must overcome a number of critical challenges to bring these new solutions to market. In his session at @ThingsExpo, Michael Martin, CTO/CIO at nfrastructure, outlined these key challenges and recommended approaches for overcoming them to achieve speed and agility in the design, development and implementation of Internet of Everything solutions wi...
19th Cloud Expo, taking place November 1-3, 2016, 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 enterpri...
In today's uber-connected, consumer-centric, cloud-enabled, insights-driven, multi-device, global world, the focus of solutions has shifted from the product that is sold to the person who is buying the product or service. Enterprises have rebranded their business around the consumers of their products. The buyer is the person and the focus is not on the offering. The person is connected through multiple devices, wearables, at home, on the road, and in multiple locations, sometimes simultaneously...
Amazon has gradually rolled out parts of its IoT offerings in the last year, but these are just the tip of the iceberg. In addition to optimizing their back-end AWS offerings, Amazon is laying the ground work to be a major force in IoT – especially in the connected home and office. Amazon is extending its reach by building on its dominant Cloud IoT platform, its Dash Button strategy, recently announced Replenishment Services, the Echo/Alexa voice recognition control platform, the 6-7 strategic...