We use networks every day as a matter of course, whether for business or personal reasons. This is a collection of articles to help you systematically understand how networks work. If you are interested in learning about network technology.

We hope that you will be able to better understand how network technology works.

VLAN(Virtual LAN)VLAN (Virtual LAN) is a technology for dividing a network with Layer 2 switches. By using VLANs on Layer 2 switches to divide the network, the logical configuration of the network can be freely decided. In addition, VLANs are not used only with Layer 2/Layer 3 switches. It is also the VLAN settings that determine how virtual servers are connected to the network.
IP Routing BasicThe ability to communicate from your PC or smartphone to a distant server, such as on the Internet, is possible because of proper routing. Routing is one of the most important aspects of network technology.

It is important to have a firm grasp of the routing mechanism, which is how data is transferred to a distant server.
How the OSPF worksOSPF (Open Shortest Path First) is the most commonly used routing protocol in enterprise networks. It is important to understand how it works in order to use OSPF effectively. This section explains how the OSPF works.
How the EIGRP worksEIGRP (Enhanced Interior Gateway Routing Protocol) is a Cisco proprietary routing protocol. When determining the optimal route, you can also determine the available backup routes. This gives you the advantage of being able to switch routes quickly in the event of a failure.
How the BGP worksBGP (Border Gateway Protocol) is a routing protocol mainly used by Internet Service Providers (ISPs) to provide Internet access services. A key feature of BGP is its ability to scale to handle vast amounts of Internet route information, allowing for flexible control over optimal route decisions.
Advanced IP routingWe will discuss more advanced IP routing technologies such as filtering route information to be advertised by routing protocols, adjusting metrics, and redistributing when using multiple routing protocols.
These advanced technologies allow you to create router/layer 3 switch routing tables the way you want them to be. It allows you to control the routes that IP packets are forwarded.
Cisco BasicCisco networking device has a large share of the enterprise network. Many non-Cisco devices also have a Cisco-like command system. Learning the basics of working with Cisco device, such as the contents of Cisco’s device configuration files and the command system, is the foundation of networking.
How to Use GNS3GNS3 is a free software that can emulate various devices including Cisco routers, etc. With GNS3, you can virtually configure and verify the operation of various systems on a PC. It’s also very useful for studying CCNA/CCNP/CCIE etc.