Classful and Classless addressing are two methodologies used in the allocation and identification of IP addresses within the Internet Protocol Version 4 (IPv4) framework. Classful addressing, which was the initial scheme, divides the IP address space into classes which determines each network’s size and its division between network and host identifiers. In contrast, classless addressing […]
What is SNMP (Simple Network Management Protocol) in Networking
Simple Network Management Protocol (SNMP) is a widely used protocol for managing and monitoring network devices on IP networks. It enables network administrators to manage network performance, find and solve network problems, and plan for network growth. In this article, we’ll take an introductory look at the protocol, see how it works, and we will […]
What is Link Aggregation (LAG) in Networking?
Link aggregation is a technique used in networking to bundle multiple physical ports on a network device to operate as a single link. The aggregated link acts as a single logical port functioning at a speed equal to the sum of the bandwidths of all of the physical links. In this article, we’ll further explore […]
How Does a Network Switch Learn MAC Addresses?
A switch is a network device that interconnects host devices at Layer 2 of the OSI model. In order to perform its function correctly, it must be able to learn the MAC addresses of the connected hosts and maintain them in a MAC address table. In this article, I’ll explain in detail how a switch […]
Introduction to Cisco EEM (Embedded Event Manager)
Cisco’s Embedded Event Manager (EEM) is a powerful tool that can be configured to detect specific events and respond to those events in specific ways. EEM was introduced in the early 2000s and is one of the earliest attempts at network automation. Even so, it is still used extensively today and remains a versatile tool […]
Comparison of Reported Distance vs Feasible Distance in EIGRP
One of the concepts involved with the EIGRP routing protocol that can sometimes be confusing is the idea of the feasible distance and the reported distance of a particular network destination. Understanding these two measurements of EIGRP is an important step in understanding some of the fundamental mechanisms of EIGRP. Definition of Terms Let’s start […]
How to Reset Cisco Router or Switch to Factory Settings
If you have had any experience with Cisco switches or routers, you know there are situations where a factory reset of the device is needed. Whether you want to reconfigure a device from scratch to get a clean configuration or repurpose a device to play a different role in the network, it’s always a good […]
BGP Multihoming – Influencing Enterprise to ISP Routing Using BGP
BGP is the de facto routing protocol deployed on the Internet. Large enterprise networks will typically run BGP on the edge of their networks to ensure that routing between the ISP and the enterprise network takes place in the best possible way. It is possible to use BGP to modify the way that the ISP […]
The Most Important Border Gateway Protocol (BGP) Timers Explained
Border Gateway Protocol or BGP is a routing protocol that uses timers as part of its operation. Various timers perform different functions, and some are used for very specialized operations that are unique to BGP. In this article, we’ll be exploring some of the most common timers used for BGP as well as some less […]
Comparison of LLDP vs CDP on Cisco Networking Devices
Link Layer Discovery Protocol (LLDP) and Cisco Discovery Protocol (CDP) are network discovery protocols that perform similar functions. These protocols operate at the Data Link layer and are used by network devices to discover information about neighboring devices connected to a local network. Although LLDP and CDP operate in a similar manner, they differ in […]
Explanation and Comparison of OSPF E1 vs E2 Routes
Open Shortest Path First (OSPF) is a popular routing protocol used in many production networks throughout the world. Understanding route types is important when designing an OSPF topology for efficient and effective operation. Among the various route types OSPF offers, the External types E1 and E2 play an important role in importing routes from outside […]
Comparison of GRE vs IPSEC Used in TCP/IP Networks
Generic Routing Encapsulation (GRE) and Internet Protocol Security (IPsec) are two related but distinctly different technologies. They can be deployed separately but can also work together (GRE over IPSec) to deliver network tunneling and security services to networks and individual users. In this article, we’ll explore these technologies to understand them, and compare them to […]
How to Find a Device MAC Address on a Cisco Switch (show mac address-table)
When performing troubleshooting or maintenance tasks on an enterprise network, it is sometimes necessary to identify the MAC address of particular devices (hosts, other switches, other network devices) that are connected to the network. On smaller networks, this is somewhat simple to achieve, however, on larger networks, it can become a challenge. In this article, […]