Currently viewing the category: "Free-tools"

Draw network diagrams online (with Cisco stencils)

By On September 17, 2011 · 1 Comment

I’m a Mac and Linux user and if you are like me, then you have the same problems drawing network diagrams. Microsoft Visio does not have a version for this platforms. I’m not saying that there are no alternatives to Visio on Mac or Linux platform, but most of them are either limited in features, expensive or need some tricks to use it (as I described in one of my early post).

Finally I’ve found [...]

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Etherape – Real time network topology and traffic flow

By On December 15, 2010 · Leave a Comment

There are numerous reasons why you would want to watch your network topology or the flow of traffic on your network. Say you are experiencing a bandwidth bottleneck. What is causing that bottleneck? Is it a particular user? A machine gone awry? How do you find out what is happening without having to walk around to every single machine on your network? Easy. The Etherape network monitor gives you a real-time graphical display of your network and the flow of traffic. Using this [...]

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How to connect Vyatta to Cisco using VirtualBox and GNS3

By On August 17, 2010 · 5 Comments

“Vyatta is  a software-based, open-source, network operating system that is portable to standard x86 hardware as well as common virtualization and cloud computing platforms. By deploying Vyatta, users benefit from a flexible enterprise-class routing and security feature set capable of scaling from DSL to 20Gbps performance at a fraction of the cost of proprietary solutions.”

Shortly, you take this piece of software, install it on a x86 machine (any decent PC with quality network card will do) and have yourself a network [...]

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Free live webinars covering the new Wireshark certification

By On August 13, 2010 · 1 Comment

What should you study? How should you study? What are the hot areas on the Exam? What are the Exam question formats? What should you watch for? What if you need to reschedule the Exam? What can you bring with you?

This are the questions that Laura Chappell will try to answer in the 4 free live webinars hosted at Chappell Seminars on from 17th to 19th of August 2010. I you are curious who is Laura Chappell, you should know [...]

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Cisco Visual Network Index (VNI)

By On March 14, 2010 · 3 Comments

Cisco Visual Network Index (VNI) is an interactive tool that can help you to forecast and analyze the growth and use of IP networks worldwide. Cisco VNI intiative includes distinct elements to provide a comprehensive view of the changing IP network landscape:

Cisco VNI Forecast is a model for the estimation of future global IP traffic growth.

This can help you to estimate global IP traffic growth using data sources like Application Type, Country and Region, Segment or Network. You can access this VNI [...]

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Great tool for testing QoS implementation

By On December 16, 2009 · 5 Comments

After my last post, some readers were asking what tool did I used for testing the QoS and how satisfied I’m with it.

The name of the tool is Packgen. According to its developer developers, “Packgen is a simple network packet generator handling diffserv markers, useful for testing network bandwidth and QoS.” It support features like:
– Network packet flows generation with given bandwidth (packets sent at each time interval depending on the bandwidth to produce and the [...]

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Draw network diagrams with Visio under Mac or Linux

By On November 12, 2009 · 7 Comments

Maybe one of the biggest loss of mine when I switched from PC to Mac, was the Microsoft Visio is not available for any other platform than Windows OS. Now, I’m not a big fan of Microsoft products, but I have to admit that they have some good products, and one of this is Visio. Like it or not, more than 75%  of the network diagrams that I get are in  VSD format, which we all know (or we should) is a [...]

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Routing + QoS + Security all free for you and your small business

By On July 9, 2009 · 2 Comments

OK, you catch me as this is not from Cisco, but is related to networking and security, so I believe it fit in the idea of this blog. What I’m talking about here?! Well, let’s assume that you are the IT guy of one small business or even your home network, and like all of us, you want what’s the best for your network. With today’s key words (even I don’t understand why) like saving, cost reduction, zero budget for new deployments no manager will [...]

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Wireshark’s most useful display filters

By On May 3, 2009 · 7 Comments

Now and then, especially when you expect less, the network crashes or encounter an issue and then you had to troubleshoot. Sometime the problem is right there, you can see it and it’s easy to fix, but in other cases you’ll have to put an eye in the packets that are traveling through it and search deeper for the solution. When it comes to network sniffing or packet capturing or whatever you want to call it, I believe that the name Wireshark (formerly [...]

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How to analyze Cisco NetFlow with FREE tool

By On March 14, 2009 · 5 Comments

NetFlow is a network protocol developed by Cisco Systems to run on Cisco IOS-enabled equipment for collecting IP traffic information. It’s proprietary and supported by platforms other than IOS, such as Juniper routers or FreeBSD and OpenBSD. Cisco routers that have the Netflow feature enabled generate netflow records; these are exported from the router in User Datagram Protocol (UDP) or Stream Control Transmission Protocol (SCTP) packets and collected using a netflow collector. Other vendors provide similar features for their routers but with different names Jflow [...]

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