Network Fundamentals: Top Picks
Network Fundamentals
LAN Network Topologies
Network topologies can take a bit of time to understand when you're all new to this kind of cool stuff, but it's very important to fully understand t…
Network Fundamentals
Network Unicast - Its role and Importance
Unicast is a communication method used in computer networking where data is sent from a single sender to a specific destination device. In this…
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
Power over Ethernet - Understanding PoE Technolog…
Power over Ethernet (PoE) was invented by PowerDsine back in 1997 and the first power injector (Midspan) was installed in 1998! Many manufacturespart…
Featured Subcategories:
Netflow Articles:
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: Monitor Bandwidth & Network Utilization…
Monitoring network traffic & bandwidth usage via Netflow is mandatory for any type and size network. Gaining visibility into user traffic, applic…
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 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…
Network Protocols:
IP Protocol
IP Protocol - Part 3: IP Classes, Network & Host…
This article explains the 'Network-ID' and 'Host-ID' concept found in IP addressing and subnetting. We analyse the structure of IP addresses and netw…
TCP - UDP Protocol Analysis
Transmission Control Protocol - Part 4: In-Depth…
This article is an introduction to the 7-page TCP Header analysis section that follows. We briefly view each section of the TCP Header and then move…
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…
Supernetting & CIDR
Supernetting In-Depth Analysis - Learn to Identif…
Our previous article served as an introduction to Supernetting, also known as Route Summarization. We covered the concept of Supernetting, how it wor…
TCP - UDP Protocol Analysis
Transmission Control Protocol - Part 2: Quick Ove…
As previously mentioned on a number of occasions, TCP is one of the two protocols that lives at the Transport layer and is used to carry data from on…
Subnetting
IP Subnetting - Part 3: Subnet Mask Bits & Analys…
So we have covered to some depth the subnetting topic, but there is still much to learn ! We are going to explain here the available subnet masks and…
Subnetting
IP Subnetting - Part 5: Subnetting Guidelines
There is always that day when you are called upon to provide a solution to a network problem. The number of problems that can occur in a network are…
TCP - UDP Protocol Analysis
TCP Header Anaylsis - Section 1: TCP Source & Des…
This section contains one of the most well-known fields in the TCP header, the Source and Destination port numbers. These fields are used to specify…
STP/ICMP Protocols:
ICMP Protocol
ICMP Protocol - Part 1: Introduction
The Internet Control Message Protocol (ICMP), is a very popular protocol and actually part of an Internet Protocol (IP) implementation. Because IP wa…
ICMP Protocol
ICMP Protocol - Part 5: Source Quench Message Ana…
The ICMP - Source Quench message is one that can be generated by either a gateway or host. You won't see any such message pop up on your workstation…
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 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…
Wi-Fi Key Generator
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VLAN Networks
VLAN Security - Making the Most of VLANs
It's easy to see why virtual LANs have become extremely popular on networks of all sizes. In practical terms, multiple VLANs are pretty much the same as h…
VLAN Networks
Comparing Traditional Flat & VLAN Networks
Designing and building a network is not a simple job. VLANs are no exception to this rule, in fact they require a more sophisticated approach because of t…
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
VLAN InterSwitch Link (ISL) Protocol Analysis
Deciding whether to use ISL or IEEE 802.1q to power your trunk links can be quite confusing if you cannot identify the advantages and disadvantages of eac…
Routing
Interior Gateway Protocol - IGRP
IGRP (Interior Gateway Routing Protocol) is a Cisco proprietary distance-vector routing protocol used in enterprise networks to exchange routing informati…
Routing
OSPF - Part 1: Introduction, OSPF Packet Structure, OS…
Open Shortest Path First (OSPF) is a popular routing protocol developed for Internet Protocol (IP) networks by the Interior Gateway Protocol (IGP) working…
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
Link State Routing Protocols
Link State routing protocols do not view networks in terms of adjacent routers and hop counts, but they build a comprehensive view of the overall network…
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…
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
Static NAT - Part 1
Static NAT (also called inbound mapping) is the first mode we're going to talk about and also happens to be the most uncommon between smaller networks.
S…
Network Address Translation - NAT
Dynamic NAT - Part 1
Dynamic NAT is the second NAT mode we're going to talk about. Dynamic NAT, like Static NAT, is not that common in smaller networks but you'll find it used…




