I’m going to start out by telling you something you probably already know. Every vendor has their own way of doing things. Sometimes it makes perfect sense, and other times you end up scratching your head wondering why that particular vendor implemented this feature or product. Since I have been spending a lot more time on wireless these days, I came across an issue that forced me to reconsider how transmit power control(TPC) actually works in a Cisco wireless deployment. I thought I would impart some of this information to you, dear reader, in the hopes that it may help you. If you spend a lot of time inside Cisco wireless LAN controllers, this may not be anything new to you.
The Need For TPC
If you have been around wireless long enough, you have probably dealt with wireless installs where all of the access points(AP) were functioning autonomously. While this isn’t a big deal in smaller environments, consider how much design work goes into a network with autonomous access points that number into the hundreds. It isn’t as simple as just deciding on channels and spinning all the access Continue reading
Just a quick note to say that Big Switch have updated their demo lab system. This is an entirely virtual lab environment that simulates a Big Switch network. You can try out both Big Cloud Fabric and Big Tap Monitoring Fabric.
The lab gives you full CLI & GUI access to a sandboxed environment, with controllers, leaf/spine switches, and endpoints. Big Switch have written a sample lab you can work through, to show off the features, but you’re not limited there. You’re free to try out whatever features you like.
If you’re interested in what they’re doing, I recommend signing up.
Load sharing in MPLS networks is always an interesting topic, and we couldn’t possibly avoid it during our MPLS-focused Tech Talks – watch the video.
After discussing the load sharing intricacies we briefly dabbled with the concept of entropy labels.
In our last post we covered what docker does with container networking in a default configuration. In this post, I’d like to start covering the remaining non-default network configuration modes. There are really 4 docker ‘provided’ network modes in which you can run containers…
Bridge mode – This is the default, we saw how this worked in the last post with the containers being attached to the docker0 bridge.
Host mode – The docker documentation claims that this mode does ‘not containerize the containers networking!’. That being said, what this really does is just put the container in the hosts network stack. That is, all of the network interfaces defined on the host will be accessible to the container. This one is sort of interesting and has some caveats but we’ll talk about those in greater detail below.
Mapped Container mode – This mode essentially maps a new container into an existing containers network stack. This means that while other resources (processes, filesystem, etc) will be kept separate, the network resources such as port mappings and IP addresses of the first container will be shared by the second container.
None – This one Continue reading
This is the last in a series of podcasts sponsored by HP, all recorded at HP’s Discover conference in Barcelona, Spain in early December 2014. The series is made up of interviews and technical discussions with HP engineers and lab geeks about products in HP’s networking portfolio. Ken Gott, Product Line Manager, joins Chris Young, Senior Solutions […]
The post PQ Show 43 – HP Networking – Beyond Traditional Network Management appeared first on Packet Pushers Podcast and was written by Ethan Banks.
The “consumerisation of IT” has an interesting side-effect. Historically people mainly used computers for work. But now that many people have smartphones, tablets and laptops at home, their perception and understanding of technology has shifted. Old assumptions about training required when upgrading applications or client operating systems may no longer apply.
This comment at The Register aligns with what I’m seeing:
…We’re at the point now where users are using Windows 8 at home and wondering why the work computer is so dated. It’s the perception of IT people that users can’t handle change holding up that change, not the ability of the users. At home that same set of users has managed quite well with updated versions of Office, updated Windows, iPads, Android tablets, Facebook, video messaging and various other completely new things. Somehow they coped without extensive training and therapy. From what I’ve seen, it’s actually IT staff who don’t like Windows 8 and are trying to keep users away from it…
I can recall being involved in Office upgrades just a few years ago, and being nervous about how that would be perceived. We were concerned that there would be major push-back, because the exact locations of the buttons Continue reading
As many are aware, CloudFlare launched Universal SSL several months ago. We saw lots of customers sign up and start using these new, free SSL certificates. For many customers that didn’t already have an SSL certificate, they were able to use “Flexible SSL”.
Flexible SSL creates a secure (HTTPS) connection between the website visitor and CloudFlare and then an in-secure (HTTP) connection between CloudFlare and the origin server. For any site using absolute links to assets (i.e. javascript, css, and image files), this can lead to a “Mixed Content” error.
What is “Mixed Content”? This can be understood as mixed protocol. When the webpage is loaded over SSL (HTTPS protocol), most browsers expect all of the assets to be loaded over the same protocol. Some browsers will display an error about loading “insecure content” while others will just block the insecure content outright.
This error only applies to pages loaded over SSL, since the browser is working to make sure that secure pages only load equally secure assets.
The latest version of the CloudFlare plugin for Wordpress works to resolve a lot of these errors by altering the protocol within the Continue reading
We closed our Series D in financing right before Christmas. This is a $50M round lead by Temasek and Ericsson. Temasek is a $170B plus sovereign fund out of Singapore that is best described as Berkshire Hathaway of Technology. They were the people responsible forinvestments into Alibaba. This is important to understand that with Netvisor achieving success in Enterprise Datacenter and Private Cloud markets, the bigger players now believe that SDN switching and applications on Server-Switches is pretty real.
The finding is primarily to scale our business side and help sell more products, build support infrastructure and create a application group that can write more applications on Netvisor to exploit the world of programmable networks.
The best way to explain this is to draw a parallel between Netvisor as a switch Hypervisor and Smartphone.
When Apple released a IOS based smartphone, the world was full of small hardware devices like camera, GPS navigators etc. IOS (and later Android) become a software platform that allowed many applications to come of top of this platform.
Netvisor is creating the same paradigm for datacenter switching. Today, you have a physical fabric, a separate Observability fabric (using TAPS and Continue reading
OSPF Open shortest path first is a dynamic routing protocol which creates a topology between the routers to distribute routing information inside an Autonomous system. If you are not familiar with OSPF, don’t worry ! In this article OSPF will be explained in great detail. Are you interested in design aspect of OSPF, many OSPF design examples will […]
The post OSPF routing protocol appeared first on Network Design and Architecture.
For whatever reason (subliminal messages from vendor marketing departments?), I’m constantly brooding about the vendor lock-in, its inevitability, and the way supposedly disruptive companies try to use the fear of lock-in to persuade na├»ve customers to buy their products.
Read more ...We’ve heard a lot of Software Defined Networking (SDN), Open Networking, APIs, and policy models over the past few months (and years). There are days where it’s sickening to hear the term SDN, but even on those darkest days, the reality is that the network industry has a bright and open future. In this post, I’m going to share a list of networking projects that I’m aware of that are not only open, but also open source. It is definitely eye opening and extremely positive to see so much open source activity in the network industry.
Edit/Note: updated list can be found here on GitHub. Feel free to issue a pull request to add or modify the list.
OpenDaylight (ODL) – established in April 2013 is an open source Software Defined Networking (SDN) controller platform(s). There are different controller platforms for different use cases.
OpenFlow (OF) – established in the late 2000s, the OpenFlow 1.0 release launched in December 2009. The Open Networking Foundation took over the development (not actually coding) of OpenFlow when ONF formed in late March / early April in 2010.
Open vSwitch (OVS) – established in mid to late 2009 by the Nicira team to Continue reading