0

Bufferbloat and Other Challenges

Vint Cerf wrote a wonderful piece on the problems I’ve been wrestling with the last number of years, called “Bufferbloat and Other Internet Challenges“. It is funny how one thing leads to another; I started just wanting my home network to work as I knew it should, and started turning over rocks. The swamp we’re in is very deep and dangerous, the security problem the worst of all (and given how widespread bufferbloat is, that’s saying something). The “Other Challenges” dwarf bufferbloat, as large a problem as it is.

I gave a lunch talk at the Berkman Center at Harvard in June on the situation and recommend people read the articles by Bruce Schneier and Dan Geer you will find linked there, which is their takes on the situation I laid out to them (both articles were triggered by the information in that talk).

Dan Geer’s piece is particularly important from a policy perspective.

I also recommend reading “Familiarity Breeds Contempt: The Honeymoon Effect and the Role of Legacy Code in Zero-Day Vulnerabilities“, by Clark, Fry, Blaze and Smith, which makes clear to me that our engineering processes need fundamental reform in the face of very Continue reading

0

Good Ansible News, Everyone

There are lots of great things happening at Ansible (and we aren't just talking about the new coffee in the breakroom). We've had a great summer with the hiring a bunch of new Ansible team members, the release of Ansible 1.7.2 and Ansible Tower 2.0. Fall is shaping up to be even better.

-- Inforworld names Ansible one of The best open source data center and cloud software companies.

Continue reading

0

How Big is That Network?

There is a careful policy path to be followed that encourages continued investment and innovation in national telecommunications-related infrastructure and services, while at the time same time avoiding the formation of market distortions and inefficiencies. What helps in this regulatory process is clear information about the state of the industry itself. One of those pieces of information concerns the market scope of the retail Internet Service Provider sector. To put it another way, how “big” is a particular network? How many customers does it serve? Is its market share increasing or falling?

0

Write Like You Mean It (Part 1)

Engineers are supposed to be able to gather information, arrange it in a way that makes sense, and then propose a solution that actually solves the problem at hand — right? So why is it I’m almost constantly astounded at the lack of writing skills in the engineering community? Why don’t engineers know how to write, given the almost complete overlap between the way the engineering process is supposed to work, and the way writing is supposed to work?

I suspect there are a number of reasons, probably foremost of which is that engineers don’t think in the logical chains we like to believe. Engineers are too often caught in the modern “search engine world” — find a thesis, search for a few exports to support your belief, and declare the issue decided. We’re sorely lacking the serious interplay between ideas, the pros and cons way of thinking, that exist in many other intellectual pursuits (though honestly, on a decreasing level every day).

If you need some encouragement, let me put it another way: learning to write will not only enhance your thinking skills as an engineer, it will also advance your career. Seriously.

What to do? Well, we can’t Continue reading

0

HP Talks SDN Turkey at Interop

Last Wednesday I had the pleasure of meeting with Chris Young and Jeff Enters from HP Networking as part of Tech Field Day Extra! at Interop NYC 2014. Going into the discussion I had expected to get a presentation on … Continue reading →

If you liked this post, please do click through to the source at HP Talks SDN Turkey at Interop and give me a share/like. Thank you!

0

OpEx savings and the ever-present emergence of SDN

Software-defined networking is fundamentally about two things: the centralization of network intelligence to make smarter decisions, and the creation of a single (or smaller number of) administrative touch points to allow for streamlined operations and to promote workflow automation. The former can potentially lead to new capabilities that make networks better (or create new revenue streams), and the latter is about reducing the overall operating costs of managing a network.

Generating revenue makes perfect sense for the service providers who use their network primarily as a means to drive the business. But most enterprises use the network as an enabling entity, which means they are more interested in the bottom line than the top. For these network technology consumers, the notion of reducing costs can be extremely powerful.

But how do those OpEx savings manifest themselves?

OpEx you can measure

When we consider OpEx, it’s easy to point to the things that are measurable: space, power and cooling. So as enterprise customers examine various solutions, they will look at how many devices are required, and then how those devices consume space, power, and cooling. It is relatively straightforward to do these calculations and line up competing solutions. Essentially, you calculate Continue reading

0

Now that We’ve Buried the Seven Layer Model…

“But the seven layer model is still useful for teaching networking…” So ran the most common reaction to my post last week about the seven layer model being dead. But let me ask something — how useful is the seven layer model for teaching networking? It doesn’t match the TCP/IP stack, it doesn’t account for […]

Author information

0

LAG versus ECMP

Bryan sent me an interesting question:

When you have the opportunity to use LAG or ECMP, what are some things you should consider?

He already gathered some ideas (thank you!) and I expanded his list and added a few comments.

Read more ...

0

Interop New York: It Was Great Fun

Last week’s Interop New York was hard work (three workshops in two days), but also lots of nerdy fun. I love doing workshops with smart participants who bring their real-life problems to the room and challenge my assumptions and conclusions, and I had plenty of these interactions during the week. Thank you all (you know who you are)!

Read more ...

0

Interop NYC & Software Gone Wild

0

CCIE RSv5 Workbook Troubleshooting Labs Now Available

Troubleshooting Lab 1 has been added to the CCIE Routing & Switching v5 Workbook. This is in addition to Full Scale Lab 1 which was posted yesterday. More Foundation, Troubleshooting, and Full Scale Labs will be added soon to the workbook. More information about additional content and its release schedule will be available shortly.

This lab uses a 20 router topology which will be available through our rack rental system shortly.  In the meantime if you have your own lab built on CSR1000v, IOU/IOL, etc. the initial configs are available to download on the lab 1 tasks page.  For technical discussion of this lab, please visit the Troubleshooting Labs section of our Online Community here.

0

Dictionary: Bra-padding

Advertise here with BSA

Bra-padding is a term used to describe fluff marketing pieces about some relatively minor advance in product or technology. Mostly favoured by large incumbent technology vendors like EMC, Cisco etc who have an over-abundance of marketing people who need something to occupy their time.

Advertise here with BSA

The post Dictionary: Bra-padding appeared first on EtherealMind.

0

Utility-Based Pricing Troubles Me

Utility, or Consumption-Based pricing models offer an interesting way of matching costs to revenues. But if they’re not managed well, customer costs could blow out just trying to keep the lights on. We’ve come to expect rapidly declining hardware prices. Have vendors realised their utility prices need to decline at a similar rate?

I’ve been doing more architecture work over the last twelve months, and this has changed some of my thinking about technology. Previously I was only really interested in speeds & feeds, and technical capabilities. Scaling was only about how to add capacity – not what it would cost. When I looked at costs, it was just to shake my head at the ridiculous prices charged for things like a second power supply.

But now I find myself interested in things like cost curves, and trying to figure out how my costs will change as demand changes. The ideal is for their to be a clear relationship between costs & revenue, hopefully with costs growing at a slower rate than demand (and revenue).

Previously we had high upfront costs to buy hardware and software, and we aimed to amortise it over the life of the service. Our costs Continue reading

0

Cisco Adds New Routers In the ISR 4000 Family

The Cisco ISR G2 routers have been around for a while now. Roughly a year ago, Cisco released the Cisco 4451-X router which was the first ISR running IOS-XE. Cisco has now added new routers to the 4000 family, which means that the ISR G2 family will eventually go away. Don’t panic though! That will not happen for a while but if you are looking to buy new ISR routers, then take a look at the new 4000 family.

One great thing about the new ISR 4000 routers is that they support upgrading of the bandwidth capacity by buying a license. That means that you can keep the same router for a longer time and grow into it, rather than doing a complete replacement as your demand for bandwidth increases. The new models are ISR 4321, 4331, 4351 and 4431.

If you need a router that does 10 Mbit/s, then you can get the 4321 and you can keep using it until you reach 100 Mbit/s. The 4331 will get you from 100-300 Mbit/s which would cover a lot of customers that I currently have.

The next slide shows some of the new features of the ISR 4000:

The ISR Continue reading

0

Show 207 – Cisco Nexus Unified Fabric – Sponsored

What’s new with Cisco Nexus Unified Fabric (formerly Dynamic Fabric Automation), you ask? Well, an integrated end-to-end solution that builds on four fundamental pillars is what’s new. The pillars are… Fabric management. Workload automation. Optimized networking. Virtual fabrics. These features are applicable across the Nexus product line from the Nexus 7K down to the Nexus 1K […]

Author information

The post Show 207 – Cisco Nexus Unified Fabric – Sponsored appeared first on Packet Pushers Podcast and was written by Ethan Banks.

0

Two Minutes of Hate: Marriot deauthing competing WiFi

The principle I want to discuss here is "arbitrary and discriminator enforcement". It was the principle behind the Aaron Swartz and Andrew "weev" Auernheimer cases. The CFAA is a vague law where it is impossible to distinguish between allowed and forbidden behavior. Swartz and Weev were prosecuted under the CFAA not because what they did was "unauthorized access", but because they pissed off the powerful. Prosecutors then interpreted the laws to suite their purposes.


The same thing is true in the Marriott case. Deauthing Wifi is common practice on large campuses everywhere, at company headquarters, hospitals, and college campuses. They do this for security reasons, to prevent rogue access-points from opening up holes behind the firewall. It's also used at the DefCon conference, to prevent hostile access-points from tricking people by using "DefCon" in their name.

Section 333 of the Communications Continue reading

0

CCIE RSv5 Workbook Full Scale Lab 1 Now Available

Full Scale Lab 1 has been added to the CCIE Routing & Switching v5 Workbook. More Foundation, Troubleshooting, and Full Scale Labs will be coming soon, including additional updates before the end of the weekend. I will post more information about additional content and its release schedule shortly.

This lab uses a 20 router topology which will be available through our rack rental system shortly.  In the meantime if you have your own lab built on CSR1000v, IOU/IOL, etc. the initial configs are available to download on the lab 1 tasks page.  For technical discussion of this lab, please visit the Full Scale Labs section of our Online Community here.

0

Who Uses the 55:4e:20 MAC OUI?

I set up a new secondary ISC DHCP server yesterday, as an interim solution while I get round to fixing a dead server. The easiest short term fix was to spin up a VM and install DHCP there. As I … Continue reading →

If you liked this post, please do click through to the source at Who Uses the 55:4e:20 MAC OUI? and give me a share/like. Thank you!

0

Renesys Team Launches Dyn Research

Welcome to the new Dyn Research Blog!   We’re certainly glad you’re here, and we hope you like the snazzy new look.

Since the Renesys team joined Dyn in May, the number one question we’ve received is “will you keep publishing the blog?”   The answer is yes, absolutely, and we hope to bring you some diverse perspectives on Internet performance from other members of the Dyn technical team as well.    Please do let us know what you think of the new Dyn Research Blog, and feel free to suggest topics you’d like us to cover.

 

A moment for reflection

Looking back over the eight years that we’ve been publishing our observations about Internet structure and operations, I’m struck mostly by how you, our audience, have evolved and grown.    In the early days, news about Internet infrastructure appealed to a pretty narrow group of readers within the network operations community.   We never had to buy beer at conferences like NANOG, but the rest of the world was more or less content to ignore the dirty details of IPv6, peering and depeering, Net Neutrality, and the evolution of the IP wholesale transit industry.

A Continue reading

0

Plexxi Pulse—HadoopWorld 2014: Is your network ready for Big Data?

We are two short weeks away from HadoopWorld, one of the world’s largest Big Data conferences. October 15—17 our team will be in in New York City to demo our Big Data fabric and answer questions about preparing networks for Big Data. Stop by booth 552 to catch up with our team and pick up a pair of Plexxi Socks. We look forward to seeing you there.

In this week’s PlexxiTube of the week, Dan Backman describes how Plexxi manages load balancing in Big Data networks.

Check out what we’ve been up to on social media this week. Have a great weekend!

The post Plexxi Pulse—HadoopWorld 2014: Is your network ready for Big Data? appeared first on Plexxi.