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about me or about this blog and how it is built

I recently purchased a used Lenovo Thinkpad T420 laptop to replace the Lenovo Thinkpad T400 I was previously using as my main platform for researching open-source network simulators and emulators. The T420 is a five-year old product but it offers all the ports and performance I need. Because it is well past its depreciation curve, anyone can purchase a used T420 for a very low price.


I wanted a computer that supports high-resolution external monitors so it required a DisplayPort output. I also wanted to expand the number of VMs I can run concurrently with adequate performance so I needed a processor that supports HyperThreading. I wanted to switch to the Ubuntu Linux distribution and the Ubuntu Unity desktop environment needs just a bit more processing power to run smoothly. The Lenovo Thinkpad T420 meets all these requirements.

Continue reading to learn more about the Lenovo Thinkpad T420, another excellent and inexpensive Linux platform.

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Blog status report 2014

August 7, 2014

The occasion of my fiftieth post is a good milestone to pause and look back on the two years since I started blogging about open-source routing and network simulation. I will review the blog’s performance statistics and reflect on why I started this blog and what I want to do next.

50th post stats

The chart above shows the blog traffic over the past two years, starting in August 2012. In the first year I thought I would reach only a small audience but, as I posted more content, more users found my blog. In the past twelve months, 29,500 unique users visited this blog. Traffic grew steadily almost every month in the past year.

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Image used is from

Image used is from

When I started researching open-source routing and networking software, I ran the open-source Linux operating system on a virtual machine running on my Apple iMac computer. When I wanted to experiment with virtualization technologies such as KVM, which will not work inside a virtual machine, I set up my iMac to dual-boot Linux and Mac OS X.

Eventually, I wanted a second computer on which I could frequently install and re-install different distributions of Linux without worrying if I would cause problems on the iMac, which is also used by the rest of my family.

I needed to buy a computer specifically for my research project. I wanted to get a good computer at a very low price. Read on to learn about the Lenovo T400 laptop computer, an excellent and inexpensive Linux platform.

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Google Webmaster Tools

March 5, 2014

Recently, Google temporarily dropped my blog from its search results. Since over 75% of my traffic comes from first-time users who find the site through search results, this effectively caused a two-day “outage” for my site.

As I tried to understand why my blog was not findable in Google, I realized that it would have been helpful to have Google Webmaster Tools set up on my hosted web site.

This post describes how to set up Google Webmaster Tools for a blog hosted on a remote server managed by a service provider, such as bluehost.

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As a personal project, for my own edification, I will research and implement systems that will allow me and anyone who follows this blog to experiment with networking technology and learn new concepts. I will not have to invent anything new. I will use the resources already created by other people who have generously made their projects available as open-source software. I expect I will learn a lot about the Linux operating system and will continue to learn new things about networking technology and applications.

Open-source switch and router software, combined with open-source server software and other open-source tools provides a set of resources that will allow a learner to simulate the functionality of complex enterprise or service-provider networks on a single personal computer.

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