Computer Networks

This post is an introduction to computer networks.

Computer Network Devices

Computer network devices includes switch, routers or firewalls.

You can read this post about computer network devices.

Area Networks

Examples of area networks are WAN or LAN.

You can read more about area networks on this post.

Network Architectures and Models

Network architectures and models:

Client-Server Model
Peer-to-peer (P2P)

Client-Server Model

The three-tier architecture is a software application architecture that organizes applications into three logical and physical computing tiers:

Presentation tier, or user interface.
Application tier, where data is processed.
Data tier, where application data is stored and managed.

Remote Management

Ingrated Lights-Out (iLO) is a proprietary remote management technology by HPE.

Network Quality of Service

Quality of Service (QoS) in networking is the use of mechanisms or technologies that work on a network to control traffic and ensure the performance of critical applications with limited network capacity.

You can read this post about network quality of service.

High Availability

High Availability (HA)

HA clustering setup types:

Active-active
Active-passive

Active-active setup distributes workloads evenly across all nodes, ensuring optimal load balancing.

Active-passive setup keeps nodes on standby, activating them only when the primary fails.

Content Delivery Network

Content Delivery Network (CDN).

You can read about them on this post.

Cabled Networks

Example of telecommunication cabling are twisted pair and fiber optic.

You can read more about telecommunication cabling on this post.

Wireless Networks

You can read this post about wireless communication.

Communication Models and Frameworks

Examples of communication models:

TCP/IP
OSI

TCP/IP

The TCP/IP framework is officially known as the internet protocol suite.

You can read this post about TCP/IP model.

OSI

Open Systems Interconnection (OSI) model appeared after TCP/IP, and it is more theoretical.

You can read this post about OSI model.

Network Protocols

You can read more about computer network protocols on this post.

Network Virtualization

Network virtualization or virtualized network is the combination of hardware and software networking components into a single integrated entity.

Network virtualization is achieved through:

VLANs (through L3 switches)
Virtual switches (cloud-distributed, etc.)
VPN
Software defined network (SDN)

VLAN

A Virtual LAN (VLAN) is a network segmentation created by a switch. A switch can have multiple VLANs, and by default all of its ports are in VLAN 1.

A VLAN operates at OSI layer level 2.

VLANs are connected between them through routers or L3 switches.

Types of VLAN:

Static
Dynamic

A static or port-based VLAN is one that is configured directly by connecting the device to specific switch ports.

Virtual Extensible LAN (VXLAN) is an encapsulation protocol that enables VLANs to be stretched across subnets and geographic distances, making two different network locations appear to be on the same segment despite distance and network differences.

It tunnels layer 2 connection over a layer 3 network, extending a LAN.

NAT

Some firewalls implement NAT.

VPN

Virtual Private Network (VPN) operates at OSI layer level 3, and also layer 4.

A VPN service offers a public VPN, usually under a fee. You can find a list of VPN services on this post.

SDN

You can read this post about software-defined Network (SDN) and software-defined WAN (SD-WAN).