SDxCentral’s Top 10 SDN and NFV Articles — November 2015
Verizon, Juniper, Cisco, and Ericsson all make the top 3.
Network Engineers Becoming System Administrators
The trend towards virtualization is expanding the duties of a network engineer beyond traditional networking into server management.Detecting NAT64 Prefix
If you’re a host running on an IPv6-only network, you might want to detect the IPv6 prefix used for NAT64 (for example, to transform IPv4 literals a clueless idiot embedded into a URL into IPv6 addresses).
Apple has a wonderful developer-focused page describing NAT64 and DNS64, including the way they synthesize IPv6 addresses from IPv4 literals. You (RFC 6919) MUST read it.
Read more ...Understanding VLAN terminology – Access Trunk Native Tagged Untagged
Ever so often I myself have searched around for the exact difference between all of the different terms associated with VLAN's (Virtual Local Area Networks) and I'm sure a lot of people out there do the same. There's so much out there explaining these terms but it gets confusing when everything is virtualized. How does networking work in a virtualized host where the operating system networking stack provide virtual network functions such as a virtual switch?
I will start out by stating that networking works the same way it is expected to work in the physical world with wires and hardware boxes that switch or route traffic. To understand what these terms mean you need to first understand how VLANs work. VLAN segregation can happen on a IP range basis, on a port to port basis on the switch, based on protocol, based on mac addresses or just based on some other higher layer abstractions. The most common implementation is however port based and I will go ahead by explaining these terms with respect to this premise. Also some of these terms are specifically defined by Cisco switches and have then on gone to become popular in network design vocabulary Continue reading
I will start out by stating that networking works the same way it is expected to work in the physical world with wires and hardware boxes that switch or route traffic. To understand what these terms mean you need to first understand how VLANs work. VLAN segregation can happen on a IP range basis, on a port to port basis on the switch, based on protocol, based on mac addresses or just based on some other higher layer abstractions. The most common implementation is however port based and I will go ahead by explaining these terms with respect to this premise. Also some of these terms are specifically defined by Cisco switches and have then on gone to become popular in network design vocabulary Continue reading
OSPF vs EIGRP for DMVPN
In this post I'm going to look at the characteristics of OSPF and EIGRP when used in a Dynamic Multipoint VPN (DMVPN). I will do my best not to play favorites and instead stick to the facts (yes, I do have a preference :-). To that end I will back everything up with data from my lab. The focus areas of the comparison will be:
- Scalability of the hub router's control plane
- Overall control plane stability
- Traffic engineering
This post won't go into any background on how DMVPN works. If you're not yet familiar with DMVPN, I recommend watching these introductory videos by Brian McGahan. This post also does not do a deep dive on OSPF or EIGRP. I'm making the assumption that you're already familiar with the different LSA types in OSPF and general functions of EIGRP.
After reading this post you should be able to describe the pros and cons of OSPF and EIGRP in the three areas listed above and incorporate this knowlege into a DMVPN design.
CCIE Written Changes
Just when you thought you were prepared for your CCIE written exam, think again! Cisco has announced that as of July 25th 2016 they will be adding the section called “Evolving Technologies” to all written exams. If you are scheduled to take your written, in any track, before July25th than not to worry, these changes will not affect you in anyway according to Cisco.
This new section is going to account for 10% of your overall score on the exam with the original topics in your blueprint coming out to 90%. The most interesting point that we need to focus on is that the subdomains of this new section are subject to change as “new and emerging technologies are developed and adopted by the industry”.
Now I know what you’re thinking, “how am I supposed to study for this?”. It’s not all that bad! Cisco has at least given us some resources that we can use to begin preparing for these new topics on our written exam. Here at iPexpert, we’ll be adding these topics to new Written VOD products accordingly, and releasing updates over the next few months.
The last big update to the CCIE blueprints that I Continue reading
Change of Venue: LinkedIn
I’m changing roles from Principal Engineer at Ericsson to the Architecture Team at LinkedIn. New adventure! But don’t worry, ‘net Work is staying open for thoughts about life as a network engineer.
The post Change of Venue: LinkedIn appeared first on 'net work.
First Internet ecommerce was at least 1990
This article from FastCompany claims that the first Internet e-commerce transaction was 1994. This isn't true. The site "cdconnection.com" was selling CDs online since 1990. Well, they claim 1990, I don't know what evidence they have. But I personally can remember buying CDs on their site for over a year before I switched jobs in mid-1994 (so probably at least 1993).I write this up because it's apparently an important concern when Internet e-commerce was "invented", so I'm writing up what I witnessed. It's a silly competition, of course, since Internet e-commerce is such an obvious idea that nobody can "invent" it. Somebody probably accepted payments for things online even before that. But, as of 1993 when I purchased music, CDconnection was a well-honed business, a "site", with an interface, with a wide selection, using Telnet with V100 commands to format the screen.
Network Break 64: Taking A Break From The Break
Network Break took a Thanksgiving break last week. Instead of news coverage, Greg and Ethan give an update on the state of Packet Pushers and talk Cisco, white box operating systems, and more.
The post Network Break 64: Taking A Break From The Break appeared first on Packet Pushers.
Network Break 64: Taking A Break From The Break
Network Break took a Thanksgiving break last week. Instead of news coverage, Greg and Ethan give an update on the state of Packet Pushers and talk Cisco, white box operating systems, and more.
The post Network Break 64: Taking A Break From The Break appeared first on Packet Pushers.
Assuming the worst is not the best assumption
It was too bad to be true, but I should have known that assuming the worst was not the best assumption. I was driving the “other” car, the Saab, on the way back from the METNAV shop around eight in the morning. Since the shop was located in the middle of the three runways, this meant I had to drive across the 18 taxiway, along the white lines painted between the C-141’s, C-130’s, KC-10’s, F-4’s, and sometimes other odds and ends, and then past the Tower, off the flightline, and onto the “surface streets.” As I was coming off a call at around three in the morning, I wasn’t in uniform. For some reason, I hadn’t driven my normal car — a white Jeep — so the folks in the Tower certainly wouldn’t recognize me.
So when the SP flipped his lights on and pulled in behind me, I was worried. Just as the lights came on, I remembered something really important: I had forgotten to put my sticker on the car. You see, to drive on the flightline, you had to have a sticker on your car. There were various colors for the different areas you could gain Continue reading
Security for the New Battlefield
What will be our security challenge in the coming decade? Running trusted services even on untrusted infrastructure. That means protecting the confidentiality and integrity of data as it moves through the network. One possible solution – distributed network encryption – a new approach made possible by network virtualization and the software-defined data center that addresses some of the current challenges of widespread encryption usage inside the data center.
VMware’s head of security products Tom Corn recently spoke on the topic at VMworld 2015 U.S., noting, “Network encryption is a great example of taking something that was once a point product, and turning it into a distributed service—or what you might call an infinite service. It’s everywhere; and maybe more importantly it changes how you implement policy. From thinking about it through the physical infrastructure—how you route data, etcetera—to through the lens of the application, which is ultimately what you’re trying to protect. It eventually becomes really a check box on an application.”
VMware NSX holds the promise of simplifying encryption, incorporating it directly so that it becomes a fundamental attribute of the application. That means so as long as it has that attribute, any packet will be Continue reading
Enter the Octagon: Cisco ACI vs. VMware NSX
Which SDN product reigns supreme? NSX vs. ACI is a contentious and closely watched battle.