BGP in Large Scale Data Centers with Clos Networks

Getting to the point where big is never big enough, one may think “What’s cooking?” Well, BGP in the DC is a subject that’s been under my radar for some time, so the purpose of this article is to get things a bit more straight-forward regarding the WHYs and HOWs.

A look in the past

First of all, we should ask ourselves who was Clos. Charles Clos started his work at Bell Labs, mainly focusing on finding a way to switch telephone calls in a scalable and cost-effective way. In 1953, he published the paper “A Study of Non-Blocking Switching Networks”, where he described how to use equipment having multiple stages of interconnections to switch calls.

The crossbar switches (you may think of them as common use switches with a defined number of ports) connected in a three-stage network (ingress, middle, egress) form the so called Clos network.

This had a pretty big use back in the 1950’s but once the level of circuit integration got to the point where interconnections would no longer be a problem, it was no longer of interest, at least for some time.  Until huge scale data centers came to be needed (and Continue reading

Resolve is easy. Planning & execution are hard.

When we fail, we pity ourselves, have a consolation cookie or three, give up, and go back to a moribund contentment with the status quo. Maybe next year, we'll be more serious, we think. More determined. Yes, we'll try it all again at some future point when we can muster up the will to give it another go. This is all wrong. For me, difficulty in realizing goals has never been due to a lack of desire or will.

What’s Wrong With the Internet?

How many times have you received that call or even made the statement that “The Internet is Down?” Or perhaps the “Internet is Slow?” Obviously these statements are very rarely true. As a whole, the Internet is functional and it is FAST. However these statements seem true from the perspective of the individual making them. My frustration is that we never have visibility into the data necessary to assess the health of the Internet from a relevant, holistic perspective over time. As a result, consumers and providers have a limited view of problems that randomly present in this manner.

The Problem

When I think about the impact Internet hiccups have on me, I realize that I could do things much differently if it delivered consistent reliability. Even if it wasn’t as reliable as infrastructures like the PSTN, having some semblance of trust in knowing when and how my connections might fail or degrade would help. The resulting improvements would allow me to use more robust tools like video and voice over the Internet and put my cell phone away. I can’t tell you how many times I’ve spent hours chasing ghosts. These transient issues tend to get resolved when they worsens and the root cause is more easily identifiable. Increasing the trust we have in our services would materially change the way in which we use them. Continue reading

Routing design

Understanding everything about routing design is no brainer, especially if you have the chart below on your wall. The table below highlights the pros and cons of each routing protocol. Of course, you need to consider the design attributes shown in Figure A before embarking on routing design. Should you like the comparison of the […]

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PQ Show 69: Sonus VellOS And QoE For Unified Communications (Sponsored)

Sonus joins the Packet Pushers to talk about VellOS, a network operating system for ensuring quality of experience for unified communications. With VellOS you can automate flows through a network and control bandwidth, packet marketing, MPLS values, and more to guarantee high-quality voice and video calls.

The post PQ Show 69: Sonus VellOS And QoE For Unified Communications (Sponsored) appeared first on Packet Pushers.

PQ Show 69: Sonus VellOS And QoE For Unified Communications (Sponsored)

Sonus joins the Packet Pushers to talk about VellOS, a network operating system for ensuring quality of experience for unified communications. With VellOS you can automate flows through a network and control bandwidth, packet marketing, MPLS values, and more to guarantee high-quality voice and video calls.

The post PQ Show 69: Sonus VellOS And QoE For Unified Communications (Sponsored) appeared first on Packet Pushers.

My Markdown Adventure

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It was almost a year ago that I set forth the idea to start writing all my blog posts in Markdown. I’ve been doing my best to keep up with that throughout the year and now I’m fifty Markdown posts into my goal. How is it working out so far?

Markdown Mindset

Learning to write in Markdown took some adjustment. Before, I had just used the web editor or the occasional HTML editing suite to write my posts. Most of the HTML was hidden. With Markdown, you have to think about what you’re going to do before you start writing it. Where are the links going to appear? How is your post going to be organized? Putting a bit more thought into your post gives you more structure to your thoughts. That’s something that’s helped my writing a bit.

The table layout for the 2015 Cisco Live Twitter List really wasn’t all that difficult either. Once I put the initial code together, it was just a simple copy/paste job after that. I’m toying with the idea of putting all my notes into Markdown as well. But given how terrible I am with taking typed notes that may not happen.

Editing Continue reading

10 outsourcing trends to watch in 2016

This year, we saw companies embrace increased standardization and cloud computing options of all flavors, use their leverage to renegotiate or rebid their deals, and settle into a best-of-breed approach to offshore outsourcing.So what will 2016 bring? Our experts expect a number of shifts in the industry—including a focus on hyper-speed deal making, the emergence of new multi-sourcing headaches and potential cures, increased man-machine collaboration, and significant expansion of the service provider universe.1. Security takes center stageSecurity is top of mind from the boardroom to the break room, and it will influence outsourcing strategy in 2016. Indeed, security risk is poised to increase as telematics and the Internet of Things (IoT) becomes more prevalent in consumer and commercial products, says Paul Roy, partner in the business and technology sourcing practice of Mayer Brown. “Increasing numbers of threat actors will use increasingly creative ways to exploit weaknesses, often with devastating effect. Regulators will exact increasingly large fines for poor security. Service providers have often been the weakest link in a company’s security and will need to find better ways to address that concern.”To read this article in full or to leave a comment, please click here

Running VLAN, VXLAN and GRE together using Neutron & Openstack

There are numerous blogs out there with step by step instructions to setup OVS networking for openstack neutron to run various types of networks. I came up with this post to best explain how everything works in the Neutron land and what a typical openstack deployment looks like. If you are looking for a more step-by-step procedure to set things up this post is a good place to start i.e. understanding the networking concepts and design behind running all the commands listed on other blogs.

A Neutron openstack deployment or any cloud environment these days typically consist of a Network Controller (SDN controller) and a cluster of compute hosts or servers. The type of networking you choose to connect all of these together is entirely upto you and I've seen various ways by which this can be done. There is no correct or right way of doing this. It's what works for you but if you don't really have anything already setup and are planning on starting afresh you could probably use this as a template to design your networking.


What you see above are three servers - one network node and two compute nodes.
First we'll go through Continue reading

Malware peddlers offered Raspberry Pi money to infect your micro-PC

The Raspberry Pi—the popular mini-PC that's about the size of credit card—is attracting attention from malware distributors. But not in the sense that you might think.Last Wednesday, the Raspberry Pi Foundation tweeted a screenshot of an email in which a company effectively asked to install malware onto users Raspberry Pis.+ ALSO ON NETWORK WORLD Ultimate guide to Raspberry Pi operating systems, part 2 +In the email, the company, whose name was redacted, offered the Foundation money in order to distribute an exe file on Raspberry Pi machines (never mind the fact that the Raspberry Pi doesn't run Windows). Installing the exe would place a shortcut icon on the desktop; if you open it, you'd be taken to the company's website. "Then this is our target," the email reads in part.To read this article in full or to leave a comment, please click here

The most innovative and damaging hacks of 2015

Not a week went by in 2015 without a major data breach, significant attack campaign, or serious vulnerability report. Many of the incidents were the result of disabled security controls, implementation errors, or other basic security mistakes, highlighting how far organizations have to go in nailing down IT security basics.But looking beyond the garden-variety attacks and vulnerabilities lends great insight into the future of malicious activity and how to defend against it. And 2015 had its share of intriguing invasions, each of which highlighted the modified techniques that lead to new forms of breaches or pinpoint areas in need of new defenses. The past year saw cyber criminals adopting innovative approaches and state-sponsored actors becoming bolder. Motivations shifted, with financial gain no longer the sole reason for launching an attack. Inflicting physical damage, stealing trade secrets, hacking as a form of protest -- 2015 was a year in which malicious activity served many ends.To read this article in full or to leave a comment, please click here

Network Break 68: Juniper Firewall Burned, 2015 In Review

Network Break 68 looks at Juniper's ScreenOS vulnerabilities, analyzes NetApp's acquisition of SolidFire, and cheers Apple for opposing U.K. surveillance. Lastly, we review of some of our favorite stories from 2015, and a list of things we probably won't care about next year. Probably.

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