Network Fundamentals: Top Picks
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 cri...
Need for Speed – The Data Tsunami & Advancement...
A long-long time ago (not long ago in earth time) 100 Mbps was THE technology. 100 Mbps uplinks bundled with ether-channel was the ultimate uplink ...
The Importance of a Network Analyzer – Packet S...
Network Analyzers, also known as Packet Sniffers, are amongst the most popular network tools found inside any Network Engineer’s toolkit. A Network...
Next-Gen Firewalls & Topologies. Designing & Bu...
Next-generation firewalls (NGFWs) and DMZ zones are two critical components of network security that work hand in hand to protect an organization's...
Featured Subcategories:
Netflow Articles:
Netflow: Monitor Bandwidth & Network Utilizatio...
Monitoring network traffic & bandwidth usage via Netflow is mandatory for any type and size network. Gaining visibility into user traffic, appl...
Complete Guide to Netflow: How Netflow & its Co...
This article will cover the basics of Netflow, including its use cases, Netflow supported devices, Netflow history, and variants. We’ll also dive i...
Netflow vs SNMP. Two Different Approaches to Ne...
SNMP (Simple Network Management Protocol) and Netflow are both popular protocols with admins, prized for their ability to give visibility over the ...
NetFlow Analyzer: Free Download, Step-by-Step I...
In our previous article we explained how a Netflow Analyzer can help you gain visibility into your user traffic, application traffic and data flows...
Network Protocols:
IP Protocol - Part 3: IP Classes, Network & Hos...
This article explains the 'Network-ID' and 'Host-ID' concept found in IP addressing and subnetting. We analyse the structure of IP addresses and ne...
TCP Header Anaylsis - Section 1: TCP Source & D...
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 specif...
The DNS Protocol - Part 1: Introduction
If you ever wondered where DNS came from, this is your chance to find out ! The quick summary on DNS's history will also help you understand why DN...
Transmission Control Protocol - Part 1: Introdu...
Understanding how each protocol fits into the OSI Model is essential for any network engineer. This page analyses how TCP is classified as a 'trans...
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 diff...
Transmission Control Protocol - Part 2: Quick O...
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 ...
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 des...
IP Subnetting - Part 1: The Basic Concepts
When we subnet a network, we basically split it into smaller networks. For example, when a set of IP Addresses is given to a company, e.g 254 they ...
STP/ICMP Protocols:
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 ...
Spanning Tree Protocol – Part 2: Rapid STP Port...
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 b...
ICMP Protocol - Part 7: Time Exceeded Message A...
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 b...
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 ...
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VLANs - IEEE 802.1q Trunk Link Protocol Analysis
While the VLAN Tagging article briefly covered the IEEE 802.1q protocol this article will continue building upon it by further analyzing the IEEE 802.1q...
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 e...
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 thei...
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 an...
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...
Interior Gateway Protocol - IGRP
IGRP (Interior Gateway Routing Protocol) is a Cisco proprietary distance-vector routing protocol used in enterprise networks to exchange routing informa...
OSPF - Part 2: How OSPF Protocol Works & Basic Conce...
This article covers basic OSPF concepts and operation. We explain how OSPF works, how OSPF tables are built on an OSPF-enabled router and their purpose ...
The IP Routing Process - Step-by-Step Analysis
We are going to analyse what happens when routing occurs on a network (IP routing process). When I was new to the networking area, I thought that all yo...