Network Fundamentals: Top Picks
Multicast - Understand How IP Multicast Works
Multicast is a communication method used in computer networking where data is sent from a single sender to a group of destination devices. In this m…
Controlling Broadcasts and Multicasts
The first step in controlling broadcast and multicast traffic is to identify which devices are involved in a broadcast or multicast storm. The follow…
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…
Hubs & Repeaters
Network hubs were once the primary method of interconnecting network devices to create a local area network (LAN). Hubs were inexpensive, easy to ins…
Featured Subcategories:
Netflow Articles:
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…
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…
ML-Based Security Analytics in NetFlow Analyzer…
This article explores how machine learning (ML) and network flow telemetry can be used to establish behavioral baselines, detect anomalous asset acti…
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:
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…
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…
TCP Header Anaylsis - Section 6: TCP Options
The TCP Options (MSS, Window Scaling, Selective Acknowledgements, Timestamps, Nop) are located at the end of the TCP Header which is also why they ar…
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 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…
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…
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…
IP Subnet Calculator
This free online Subnet Calculator provides a fast and easy way to calculate all aspects of any IP Address and Subnet Mask. Simply enter your desir…
STP/ICMP Protocols:
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…
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 - 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 – 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…
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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…
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…
Static VLANs
VLANs are usually created by the network administrator, assigning each port of every switch to a VLAN. Depending on the network infrastructure and securit…
Dynamic VLANs
Dynamic VLANs were introduced to grant the flexibility and complexity(!) that Static VLANs did not provide. Dynamic VLANs are quite rare because of their…
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…
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…
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…
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…