Network Fundamentals: Top Picks
Measuring Network Performance: Test Network Throu…
Measuring network performance has always been a difficult and unclear task, mainly because most engineers and administrators are unsure which approac…
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…
The Importance of a Network Analyzer – Packet Sni…
Network Analyzers, also known as Packet Sniffers, are amongst the most popular network tools found inside any Network Engineer’s toolkit. A Network A…
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…
Featured Subcategories:
Netflow Articles:
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…
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 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 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:
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 - Part 1: Binary & The Internet Proto…
To understand the Internet Protocol, we need to learn and understand Binary. It is very important to know and understand Binary because part of the I…
Transmission Control Protocol - Part 1: Introduct…
Understanding how each protocol fits into the OSI Model is essential for any network engineer. This page analyses how TCP is classified as a 'transpo…
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…
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…
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…
TCP Header Anaylsis - Section 5: TCP Window Size…
Our fifth section contains some very interesting fields that are used by the TCP transport protocol. We see how TCP helps control how much data is tr…
TCP Header Anaylsis - Section 2: TCP Sequence & A…
This page will closely examine the Sequence and Acknowledgement numbers. The very purpose of their existence is related directly to the fact that the…
STP/ICMP Protocols:
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…
ICMP Protocol - Part 7: Time Exceeded Message Ana…
The ICMP - Time Exceeded message is one which is usually created by gateways or routers. In order to fully understand this ICMP message, you must be…
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…
ICMP Protocol - Part 2: Echo / Echo Reply (Ping)…
As mentioned in the previous page, an Echo is simply what we networking engineers call a 'ping'. The Echo Reply is, as most would guess, the 'p…
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VTP Protocol - In-Depth Analysis
The previous article introduced the VTP protocol, we examined how it can be used within a network, to help manage VLANs and ease the administrative overhe…
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…
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…
VTP Pruning
VTP (VLAN Trunking Protocol) pruning is a feature that is used in Cisco switches to reduce unnecessary traffic in VLAN (Virtual Local Area Network) trunks…
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…
Enhanced Interior Gateway Routing Protocol - EIGRP
Enhanced Interior Gateway Routing Protocol (EIGRP), similar to IGRP, is a Cisco proprietary routing protocol that is used to exchange routing information…
OSPF - Part 5: Analysis of OSPF Link State Update (LSU…
This article explains how OSPF uses Link State Advertisement (LSA) to exchange information about the network topology between routers. When a router recei…
Introduction to Routing Protocols
Distance Vector, Link State RIP, IGRP, EIGRP, OSPF
Routing protocols were created for routers. These protocols have been designed to allow the exchange…