Network Fundamentals: Top Picks
Network Fundamentals
Securing Your Home Network
In today's world, securing your home network is more important than ever. With the increasing number of cyberattacks, data breaches, and online fraud…
Network Fundamentals
Network Switches & Bridges
Network Switches are the evolution of Hubs and Repeaters, and enable the creation of networks by connecting multiple devices together. They are criti…
Network Fundamentals
Network Data Transmission
Network data transmission refers to the process of sending and receiving information between two or more devices connected to a network. It is a crit…
Network Fundamentals
Firewall Topologies
In this section we are going to talk about the different ways a firewall can be set up. Depending on your needs, you can have a very simple firewall…
Featured Subcategories:
Netflow Articles:
Netflow
Complete Guide to Netflow: How Netflow & its Comp…
This article will cover the basics of Netflow, including its use cases, Netflow supported devices, Netflow history, and variants. We’ll also dive int…
Netflow
NetFlow Analyzer: Free Download, Step-by-Step Ins…
In our previous article we explained how a Netflow Analyzer can help you gain visibility into your user traffic, application traffic and data flows w…
Netflow
Netflow vs SNMP. Two Different Approaches to Netw…
SNMP (Simple Network Management Protocol) and Netflow are both popular protocols with admins, prized for their ability to give visibility over the ne…
Netflow
Bandwidth Detective: Uncover Hidden Traffic and E…
In this article, we explore the core principles of bandwidth management and examine how modern network monitoring technologies can assist in maintain…
Network Protocols:
Domain Name System (DNS)
The DNS Protocol - Part 3: DNS Query Message Form…
This section will deal with the analysis of the DNS packets by examining how DNS messages are formatted and the options and variables they contain. T…
TCP - UDP Protocol Analysis
TCP Header Anaylsis - Section 3: TCP Header Lengt…
The third field under close examination is the TCP Header length. There really isn't that much to say about the Header length other than to explain w…
Subnetting
IP Subnetting - Part 2: Subnet Masks & Their Effe…
There are a few different ways to approach subnetting and it can get confusing because of the complexity of some subnets and the flexibility they off…
TCP - UDP Protocol Analysis
TCP Header Anaylsis - Section 7: TCP Data Payload…
Finally, the last page of our incredible TCP Analysis. As most of you would expect, this section is dedicated to the DATA section that follows the TC…
Domain Name System (DNS)
The DNS Protocol - Part 2: DNS Queries & Resoluti…
This section will help you understand how the DNS queries work on the Internet and your home network. There are two ways to use the domain name syste…
Subnetting
IP Subnetting - Part 4: Routing Between Subnets
Routing and Communication between subnets is the main topic here. This article analyses communications between subnets. We provide examples on differ…
Supernetting & CIDR
The Supernetting / CIDR Chart
This articles build upon our previous pages covering what is Supernetting (Route Summarization) & How Supernets Work and Supernetting In-De…
IP Protocol
IP Protocol - Part 2: The Internet Protocol (IP)…
This article examines the Internet Protocol (IP) and its position within the OSI Model. We take a look at the IP Header and all fields contained with…
STP/ICMP Protocols:
ICMP Protocol
ICMP Protocol - Part 4: Destination Unreachable M…
The 'ICMP Destination unreachable' message is quite interesting, because it doesn't actually contain one message, but infact six! This means that the…
Spanning Tree Protocol (STP)
Spanning Tree Protocol – Part 2: Rapid STP Port C…
Spanning Tree Protocol, Rapid STP port costs and port states are an essential part of the STP algorithm that affect how STP decides to forward or blo…
Spanning Tree Protocol (STP)
Spanning Tree Protocol – Part 1: Understand STP P…
One of the most used terms in network is LAN (Local Area Network). It’s a form of network that we encounter in our daily lives, at home, at work, stu…
ICMP Protocol
ICMP Protocol - Part 6: Redirect Messages
The ICMP - Redirect Message is always sent from a gateway to the host and the example below will illustrate when this is used.
Putting it simply (be…
Wi-Fi Key Generator
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Cisco Password Crack
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VLAN Networks
VLAN Tagging - Understanding VLANs Ethernet Frames
We mentioned that Trunk Links are designed to pass frames (packets) from all VLANs, allowing us to connect multiple switches together and independently co…
VLAN Networks
VLANs - Access & Trunk Links
If you've read our previous article The VLAN Concept - Introduction to VLANs then you should feel comfortable with terms such as 'VLAN', 'Stati…
VLAN Networks
InterVLAN Routing - Routing between VLAN Networks
This article deals with the popular topic of InterVLAN routing, which is used to allow routing & communication between VLAN networks. Our article anal…
VLAN Networks
The VLAN Concept - Introduction to VLANs
We hear about them everywhere, vendors around the world are constantly trying to push them into every type of network and as a result, the Local Area Netw…
Routing
OSPF - Part 6: OSPF LSA Types - Purpose and Function o…
Our previous article explained the purpose of Link State Update (LSU) packets and examined the Link State Advertisement (LSA) information contained within…
Routing
Routed Protocols
We all understand that TCP/IP, IPX-SPX are protocols which are used in a Local Area Network (LAN) so computers can communicate between with each other and…
Routing
Routing Information Protocol - RIP
Routing Information Protocol (RIP) is a distance-vector routing protocol that is commonly used in small to medium-sized networks. It is one of the o…
Routing
OSPF - Part 3: OSPF Adjacency & Neighbor Forming Proce…
This is the thrid article of our 6-part OSPF series (see below) that describes how OSPF routers perform neighbor relationship and adjacency. We’ll examine…
Network Address Translation - NAT
Network Address Translation (NAT) Overload - Part 1
NAT Overload is the most common NAT method used throughout all networks that connect to the Internet. This is because of the way it functions and the limi…
Network Address Translation - NAT
Static NAT - Part 2
The previous page (Static NAT - Part 1) helped us understand what exactly happens with Static NAT and how it works, and we saw a few examples of how to us…
Network Address Translation - NAT
The Network Address Translation Table
After that simple and informative introduction to the NAT concept, it's time to find out more about how it works and this is where the NAT table comes in…
Network Address Translation - NAT
Network Address Translation (NAT) Concepts
Before we dive into the deep waters of NAT, we need to make sure we understand exactly what NAT does. So let me give you the background of NAT, why it's h…





