Communication is key in modern life. Emails, phone calls, video calls are obvious examples. But, video streaming, ecommerce, eLearning, gaming etc are also a kind of communication. We are performing some type of communication in most of our life aspects. Successful communication requires that all participating parties know how to “talk” to each other and, […]

Dynamic routing protocols are used by Layer 3 network devices to automatically share routing information.  Various routing protocols have been developed over the years, but most fall into one of three categories: Interior Gateway Protocol – Distance vector, such as EIGRP or RIP Interior Gateway Protocol – Link state, such as OSPF or IS-IS Exterior […]

The Internet Protocol (IP) is the fundamental protocol that enables end-to-end communication between hosts on the Internet. Living in the Network Layer of the OSI model, IP is able to reach the intended host by simply using the destination IP address and the routing protocols that have been configured on the networks between the hosts. […]

Network Address Translation (NAT) is a feature that enables the translation of IPv4 addresses.  It is most often used to translate private IPv4 addresses to public routable IPv4 addresses.  This feature has almost singlehandedly vastly increased the longevity of the IPv4 protocol as the primary Network Layer protocol running on the Internet, since it resolves […]

Open Shortest Path First (OSPF) and Routing Information Protocol (RIP) are two of the most well-known Internal Gateway Protocols (IGPs) among network professionals and enthusiasts alike.  Both are among the oldest routing protocols developed for IP networks, but they have evolved in very different ways, and are ultimately used today for very different purposes. Let’s […]

Open Shortest Path First (OSPF) and Enhanced Interior Gateway Protocol (EIGRP) are two of the most popular Internal Gateway Protocols (IGPs) employed in today’s modern IP networks.  Both are mature protocols, having been around for decades, and are extremely reliable, flexible, and highly configurable.  And yet, they are surprisingly dissimilar in their architecture, implementation, and […]

Every network engineer is familiar with Cisco, and with its multiple brand acquisitions, it’s even become a household name for consumers in addition to business professionals. Cisco isn’t the only major player in the hardware and TCP/IP networking game, however. This technology giant has at least a dozen formidable competitors, many of which have developed […]

A few decades ago, flat networks were the norm. I remember in my very first job as a network engineer, most of our clients’ networks consisted of a single broadcast domain (VLAN) and a huge single flat Layer 3 network (usually in the 10.0.0.0 range). As time passed by and networks started to become bigger […]

In this article we’ll discuss and examine the Syslog Protocol which runs over its default UDP port 514 (or the secure TCP port 6514), and also describe the characteristics and usefulness of Syslog in networks. All computer systems and network devices generate a historical record of events that take place on the device. This record […]

Prepare to peek under the covers of how your data can travel from as little as a few inches to thousands of miles from device to device and through tens of network devices in the path. In this article, we will explore the differences between a layer 3 Internet Protocol (IP) Packet and a layer […]