The Evolution of Network Programmability
This post is the “text” version of a talk I gave at Cisco Live US 2014 titled “SDN: People, Process, and Evolution”. While there is certainly some technical details involved here, this topic is really more of a philosophical one, and it is very near and dear to my heart as I talk with more folks about how networking is going to evolve in the years to come. The Problem with Networking Most of my readers would consider themselves network engineers - folks that live and breathe networking and everything that’s required to build them.Pylint Errors – Final Newline Missing
I recently ran into a slew of errors when using Pylint - a sort of “quality checker” for your Python code. If you haven’t used it yourself, I highly recommend you check it out - it WILL make you a better Python coder.(Thanks to Matt Stone for introducing me!) This particular error is common if you forget to append a newline character to the end of your python script, but I was getting one for every single line of code in my program.The Evolution of Network Programmability
This post is the “text” version of a talk I gave at Cisco Live US 2014 titled “SDN: People, Process, and Evolution”. While there is certainly some technical details involved here, this topic is really more of a philosophical one, and it is very near and dear to my heart as I talk with more folks about how networking is going to evolve in the years to come. The Problem with Networking Most of my readers would consider themselves network engineers - folks that live and breathe networking and everything that’s required to build them.Pylint Errors – Final Newline Missing
I recently ran into a slew of errors when using Pylint - a sort of “quality checker” for your Python code. If you haven’t used it yourself, I highly recommend you check it out - it WILL make you a better Python coder.(Thanks to Matt Stone for introducing me!) This particular error is common if you forget to append a newline character to the end of your python script, but I was getting one for every single line of code in my program.Lessons from APL, a “lost” language
Lessons from APL, a “lost” language
A few weeks back the forum that I go on often held a obfuscation challenge, and people joked around about submitting a entry that was coded in APL.
APL (A Programming Language) is a programming language that w
Internets of Interest for 24th May 2014
Collection of useful, relevant or just fun places on the Internets for 24th May 2014 and a bit commentary about what I’ve found interesting about them: Google: ‘EVERYTHING at Google runs in a container’ • The Register – Containers are going to add to the complexity of virtual networking. With Google saying that they […]
The post Internets of Interest for 24th May 2014 appeared first on EtherealMind.
Open vSwitch 201 & 301
[Special and huge thanks to Scott Lowe for answering an endless amount of questions I had while writing this post and testing with NSX/OVS over the last few days. Thanks to Deepesh as well who I bounced OVS questions off of when I needed to give Scott a break. ]
In Open vSwitch 101, I described the three main components that make up Open vSwitch (OVS) from an architectural standpoint, namely ovs-vswitchd, ovsdb-server, and the fast path kernel module. If you start to work with OVS, the first thing you realize is that it takes quite a bit more knowledge to really understand it. This post will focus on some design principles and options when running OVS on a hypervisor like KVM in conjunction with a network virtualization solution.
In Open vSwitch 101, I described the three main components that make up Open vSwitch (OVS) from an architectural standpoint, namely ovs-vswitchd, ovsdb-server, and the fast path kernel module. If you start to work with OVS, the first thing you realize is that it takes quite a bit more knowledge to really understand it. This post will focus on some design principles and options when running OVS on a hypervisor like KVM in conjunction with a network virtualization solution.
To make this a little more practical, we will use a scenario which consists of a KVM host with 3 physical NICs – 1 x 1G and 2 x 10G. The 1G interface will be used for management and the 2 x 10G interfaces will be used for actual transport of VM traffic.
This example will also assume the use of an overlay network virtualization solution Continue reading
This example will also assume the use of an overlay network virtualization solution Continue reading
News Roundup: Embrane, Cisco Prime NCS, F5 and VMware
Cisco Live happened in the US this week and it seems like a good time to briefly summarise a few of the anouncements that I saw. Embrane Pivots Embrane announced that they will be offering: …. lifecycle management for virtual network service delivered within Cisco ACI™. The company also announced plans for integrating the Embrane […]
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BGP dampening – punishment for unstable BGP prefixes
How does the internet work - We know what is networking
BGP prefix flapping can be caused by different issues in network. Basically every unstable network where links are unreliably and are going up and down here and there can cause BGP prefix flapping. Every prefix flap will cause some networks to became unreachable. BGP process will then need to recalculate best-path in order to hopefully […]
Welcome to the IP address Lookup tutorial
A router’s main function is to forward an incoming packet to its destination by using routing and forwarding techniques. Forwarding can be defined as taking the incoming packet, looking at its destination IP address, consulting the forwarding table, and directing the packet to the appropriate next-hop and output link based on the information retrieved from the forwarding table. On the other hand, routing is the process by which the forwarding table itself is built. Forwarding is a relatively simple process performed locally at the router, whereas routing depends on a variety of distributed dynamic and static routing protocols.
To consult the forwarding table, the router uses the packet’s destination IP address as a key to retrieve the forwarding information (e.g., next-hop and output interface) – this operation is called IP address lookup. Once the forwarding information is available, the router transfer the packet from the incoming interface to the appropriate outgoing interface.
The greatest challenge and major bottleneck is how to make the IP address lookup fast enough to keep up with backbone routers that support high data rate interfaces (up to 10 Gbps and more). Therefore, they must be able to perform millions of address lookup operations Continue reading
The Difference Between SDN, Automation and Orchestration
An explanation of the difference between SDN, Automation and Orchestration.
The post The Difference Between SDN, Automation and Orchestration appeared first on EtherealMind.
A Short Update on CML from #CLUS
Hey everyone,
I’ve been having a really good time here at Cisco Live US. Here is a short update on CML.
General Info
CML is being released end of June or beginning of July. The corporate edition with
a base license and support for up to 15 nodes will be listed at around 13000$ per year.
If you subscribe for two years, the discount is 5% and for three years it is 10%
Normally 15 nodes cost around 13000$ per year so basically you get 5 nodes for “free”
if you get the base package which has the SKU R-CML-CE-K9=.
IOS will be supported by running IOSv. Every IOSv image requires around 512 MB of memory.
System Requirements:
- The Cisco Modeling Labs server runs on VMware ESXi 5.0, 5.1, and 5.5.
- Recommended – Cisco UCS®
- C220 M3 Rack Server with 16 core CPU and 128 GB memory or Cisco UCS
- C460 M2 High-Performance Rack Server or higher model (actual memory and CPU consumption depends
on the number of virtual nodes and virtual network OS types). To help determine the appropriate memory
please find the Cisco Modeling Labs Calculator at http://www.cisco.com/go/cml. - Following are the minimum hardware Continue reading
Renesys, Dyn Join Forces
Today, we’re announcing the acquisition of Renesys by Dyn, the leading provider of Internet Performance solutions. Dyn and Renesys represent the perfect combination of Internet Intelligence assets from Renesys and Traffic Management and Message Management solutions from Dyn. We’re excited to become part of the Dyn team!
Those who know both companies may ask, “What took you so long?” Our headquarters are located blocks apart in beautiful downtown Manchester, New Hampshire, and the two founding teams have known each other for years. Dyn and Renesys share a surprising amount of cultural DNA – building scalable global infrastructure, understanding the economics and performance of the Internet at a deep technical level, and helping our customers deliver smarter, faster service worldwide.
Why Renesys? Why Dyn?
Renesys builds network performance management products for the Internet. We help enterprises tackle the strategic and operational challenges of delivering service over the public Internet, to consumers and businesses beyond the firewall. We operate a best-in-breed global Internet measurement platform, performing over a billion measurements each day to assess the Internet’s health and function. Anywhere in the world, when a decision maker needs insight into local Internet infrastructure, performance impairment, economics, competition, or strategy, we Continue reading
Response: NFV: Will vRouters ever replace hardware routers?
I'm not the only person pointing out the software routers are reaching unprecedented performance levels.
The post Response: NFV: Will vRouters ever replace hardware routers? appeared first on EtherealMind.
NFV: Will vRouters ever replace hardware routers?
When i started looking at NFV, i always imagined it being relegated to places in the network that would receive only teeny weeny amount of data traffic since the commodity hardware and software could only handle so much of traffic. I also naively believed that it would be deployed in networks where customers were not uber-sensitive to latency and delay (broadband customers, etc). So if somebody really wanted a loud bang for their buck they had to use specialized hardware to support the network function. You couldnt really use Intel x86-based servers running SW serving customers for whom QoS and QoE were critical and vital. The two examples that leap to my mind are (i) Evolved Packet Core (EPC) functions such as Mobility Management Entity (MME) and BNG environments where the users need to be authorized before they can expect to receive any meaningful services.
While i understood that servers were getting powerful and Intel was doing its bit with its Data Plane Development Kit (DPDK) architecture, it didnt occur to me till recently that we would be seeing servers handling traffic at 10G+ line rate. Vyatta, a Brocade company now, uses vRouters to implement real network functions. Vyatta started with its modest 5400 vRouter that could Continue reading
How Does This Help Aruba Networks?
I was going over my YouTube subscriptions tonight, as I do at least once a week, and came across this video from Aruba Networks:
While I do love watching things go through a shredder, I fail to see the point of this video. It begs the question: Who watches this and would this video change their mind?
In my opinion, this video is aimed at a non-technical buyer. If you make a significant investment in Aruba based on this video, I have serious concerns about your ability to make sound judgements when it comes to technology. That is not to say that the AP-225 from Aruba can’t beat a Cisco 3702 AP in testing. I honestly don’t know. I have access to both AP’s, and I suppose I could run my own independent tests, but to what aim? I certainly don’t have 20 laptops laying around to run my own version of this test, and I am struggling to locate the exact testing methodology used on the Aruba website. The video mentions that Aruba publishes the exact test they performed. I assume it is available somewhere. There was nothing in the video description, so I suppose I have to do Continue reading
40th Anniversary of the TCP Protocol
40th Anniversary of the TCP Protocol
by Brian Boyko, Technology Contributor - May 20, 2014
In May of 1974, the IEEE published a paper titled “A Protocol for Packet Network Intercommunication.” The authors were Vint Cerf and Bob Kahn.
Forty years later, the protocol they developed, TCP, is still the undisputed king of “sending stuff.” It’s no longer alone in packet types, but we still use the conventions for routing and interconnecting networks that TCP established, and the basic operation hasn’t changed since 1974.
It’s a brilliant design; one that, at its most simple, comes down to a single idea: it doesn’t matter where the packets come from, how fast they get there, what order they get there, or even how many copies there are of that packet on the network - so long as they get there.
The TCP receiver can simply reassemble the sequence as it was originally transmitted, and double-check with the sending computer to ensure accuracy. The TCP slow-start means that it automatically determines the safe rate at which to send packets.
The upshot of all of this has been that TCP enabled, for the first time, the building of robust Continue reading
Show 189 – Connecting VMware to the Network
I managed to get Chris Wahl to sit down for a while and talk about where VMware ESX and networking connect. In this podcast we talk through the nature of the “VMware vSwitch” and how it’s advanced patch panel capabilities can be integrated with the physical network. Chris is well known figure in the VMware scene and recently […]
Author information
The post Show 189 – Connecting VMware to the Network appeared first on Packet Pushers Podcast and was written by Greg Ferro.
When Vision Becomes Reality
plat . form
/’patfÔrm/
noun
- an underlying computer system on which application programs can run
Working at a start-up that’s trying to create an entirely new way of doing something can take your emotions on a roller coaster ride. One minute you’re loving the fact that you’re working your tail off to create something new, innovative and different; and the next minute you’re frustrated because change takes time and you want to prove that the vision the team is chasing, but not everyone is there yet.
For the Embrane family, today is a moment when we’re reminded why we put in those hours and push through those challenges.
If you’ve followed the Embrane story, you know we’ve been touting our plans to be THE platform for delivering virtual network services to enterprises and service providers. The vision Dante and Marco had when they started Embrane was that the Embrane heleos platform not only would power our own agile network services, but we would deliver that value to third-parties. We’ve listened to our customers, identified trends and evolved our solution to prove our platform was indeed a system on which application programs can run. We spent countless hours building the premier platform Continue reading