To emulate the operation of IP networks, the CORE Network Emulator requires that routing and networking software be installed on the host Linux system. CORE creates virtual nodes using the Linux Containers (LXC) network namespaces feature so all services installed in the host computer will be available to run on the virtual nodes created by […]
When I started a CORE Network Emulator simulation scenario on my computer running the Xubuntu Linux 13.10 operating system, I encountered a few issues that I needed to correct. The Ubuntu Network Manager drops my WiFi connection after I start the CORE simulation scenario and the Terminal does not start when I double-click on a
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
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
TinyCore Linux is very suitable for devices like routers that require a higher level of security. All changes made to a running TinyCore Linux system exist only in system RAM and are lost when the system restarts or is shut down. Viruses or file corruption can be removed simply by rebooting the system. When used
Psimulator2 is a basic graphical network simulator created and used by the Czech Technical University in Prague, Faculty of Information Technology to teach basic networking topics. It will run on any system that supports Java, including Windows, Mac OS, and Linux. Each node created in the Psimulator2 network is a Java program that implements the
In a previous post, I showed how to install the Marionnet open-source network simulator on a Debian Linux system. Recently, I installed Marionnet on a Knoppix system so I can run it on any computer from a USB thumb drive. Knoppix is based on Debian but, by default, it uses the LXDE desktop environment instead
GNS3 can be used to simulate a network composed exclusively of open-source routers, switches, servers, and hosts. In this post, we will investigate how well GNS3 works when we use it strictly as an open-source network simulator, without using Cisco or Juniper routers in the simulation.
To run virtual nodes in a simulated network, the GNS3 open-source network simulator supports two virtualization technologies: Qemu and VirtualBox. The open-source routers we will use in a GNS3 simulated network must run on either a Qemu or a VirtualBox hypervisor. Depending on one’s requirements, one might choose either VirtualBox or Qemu. Let me tell
GNS3 is a very popular network simulation tool that runs on the major operating systems: Windows, Mac OS, and Linux. GNS3 is primarily used to emulate networks of Cisco routers and is used by professionals studying for Cisco certification exams. GNS3 supports Cisco router software images running on the Dynamips hardware emulation program. GNS3 also
Virtual Networks over Linux (VNX) is an open-source network simulation tool that builds and modifies virtual network test beds automatically from a user-created network description file. In its current version, VNX supports several different virtualization methods: KVM, user-mode linux, and DynaMIPS. VNX was developed by the Telecommunication and Internet Networks and Services (RSTI) research group
In this post, I describe the procedure I followed to install the VNX Network Simulator on a computer running the Ubuntu Linux 13.10 operating system. The VNX system consists of the VNX program that parses the scenario description XML file and builds and manages the virtual network elements; XML files that contain a description of