Traditional ARP
As we’ve learned before, the Address Resolution Protocol (ARP) is the process by which a known L3 address is mapped to an unknown L2 address. The purpose for creating such a mapping is so a… Read More »Traditional ARP
Routing Between VLANs & Layer 3 Switches
We wrote an article which covers Virtual Local Area Networks (VLANs) as a concept, and another article on configuring VLANs on Cisco switches. The remaining subjects to cover are the different options that exist for routing between… Read More »Routing Between VLANs & Layer 3 Switches
Configuring VLANs on Cisco Switches
We’ve before written about VLANs and what they can do as a concept. This article will focus on configuring VLANs on Cisco switches. We will look at each command necessary to configure the topology below.… Read More »Configuring VLANs on Cisco Switches
Virtual Local Area Networks (VLANs)
Virtual Local Area Networks, or VLANs, are a very simple concept that has been very poorly defined by the industry. This article will explain VLANs from a practical perspective. It will be framed around the… Read More »Virtual Local Area Networks (VLANs)
EIGRP Feasibility Condition
EIGRP is a routing protocol whose strategy to prevent routing loops is based upon what is known as the EIGRP Feasibility Condition. EIGRP also makes use of another concept called Split Horizon, which we will… Read More »EIGRP Feasibility Condition
EIGRP Metric
The EIGRP Metric has caused confusion for many network engineers trying to understand the protocol. This article will dive into what the metric is, and how to boil it down into its simplified form. Formula… Read More »EIGRP Metric
Understanding EIGRP
Anyone who has ever studied the EIGRP protocol has at some point or another been confused by the awkwardly defined terminology that is incorporated into the protocol. This article’s purpose will disambiguate all the EIGRP… Read More »Understanding EIGRP
Square and Multiply
We’ve all done math problems that look like this: 35, 410, or N37. These are known as an exponentiation. And there is a trick to solving these problems with less calculations than simply multiplying the base… Read More »Square and Multiply