IT Knowledgebase Articles

The ping command is irreplaceable when it comes to troubleshooting. At some point, you will undoubtedly use this command to solve a networking problem. But how do you properly use this command in the Cisco IOS? There is more to it than you might think. What Are The Basics of Ping? The ping command works…

In a previous article, we explained the OSI model and how it works. In that article, we went over how the OSI model is a standard theoretical model for how networking hardware, software, protocols work together. What we didn’t discuss in that article is how the OSI model can help you in your day to…

Most Cisco devices do not have a graphical Web-based interface by default.  You must configure them from the command line using the serial-based console port on the switch or router.  While there are a variety of serial terminal emulation programs available, most people use HyperTerminal to do this because it is included free with Windows. …

In Part 1 of this article, we explained how access-lists work. In this article, we’ll take a sample network and explain how to create and apply an access-list. Remember that an Access-List (ACL) is used to specify network traffic. Once you specify traffic with an ACL, you can then do a variety of things with…

A Cisco IOS Access-List (ACL) is used to specify network traffic. Once you specify traffic with an ACL, you can then do a variety of things with it. For example, you could allow it, deny it, limit it, or use it to restrict routing updates. In this article, we will learn the basics of Cisco…

As a network administrator, you must be able to configure your routers to route traffic across the network. Static routes are commonly used on routers to accomplish this. For a network admin, knowing how to use a static route is a requirement. Let’s learn about static routes, and how to properly use them. Static vs….

Lost the password to your Cisco switch? David Davis walks you through how to recover that password (and your sanity).

Maybe you have a new router or you want to verify that you have security properly configured on your existing router. Either way, password security is critical to properly securing your Cisco router. So let’s get started configuring passwords on your Cisco router. Types of Cisco Router Passwords When it comes to basic password security,…

In this article, we will take a step further in securing our Cisco router by using a local username / password database in the Cisco IOS. Thus, a user must know a username AND password to be granted access to the Cisco IOS. Let’s see how this is done. Local Authentication The most basic level…

Why is your router’s Ethernet interface called Ethernet0/0 on one router but Ethernet 3/0 on another router? Where do these names come from? This article will explain how Cisco router interfaces get their names. Where do Router Interfaces get their names? Router interfaces get their names when the router boots.  A “device discovery” takes place…