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BGP Oldest Path

BGP is the predominant dynamic routing protocol used to exchange routes between different autonomous systems. BGP’s popularity lies in the Path Selection process which allows extremely granular control of the path for incoming and outgoing traffic. One of the steps in this process states that if a tie still exists between two paths, BGP will […]

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Communication through Multiple Switches

Communication through Multiple Switches

In a previous article we demonstrated how a single switch functions. One of the most frequent requests I receive is asking how the process would be different if there were multiple switches. This article will illustrate the process using two switches. In the Packet Traveling series, we discussed the four specific functions of a switch: Learning, Flooding, Forwarding, […]

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Routing Between VLANs

We wrote an article which covers Virtual Local Area Networks (VLANs) as a concept, and another article on configuring VLANs on Cisco witches. The remaining subject to cover is the different options that exist for routing between VLANs. Why do we need Routing Between VLANs? As we learned in a prior article, VLANs create a logical separation […]

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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. If this topology looks familiar, it is because you saw it in the article which described how VLANs operated on […]

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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 two major functions of VLANs, and then concluded with another equally poorly defined concept, the Native VLAN. Finally, at the […]