Network Fundamentals: Top Picks
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…
Need for Speed – The Data Tsunami & Advancements…
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 te…
Media Access Control - MAC Addresses
A MAC address, or Media Access Control address, is a unique identifier assigned to a network interface controller (NIC) for use as a network addres…
Introduction to Content Switching - Application &…
Content switches (also sometimes called application switches) is a class of network device that is becoming increasingly common in medium to large si…
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…
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: 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 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 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 DNS…
What is Supernetting (Route Summarization) & How…
Supernetting is the opposite of of subnetting, and is also known as route aggregation or CIDR (Classless Inter-Domain Routing). Supernetting is a tec…
Transmission Control Protocol - Part 3: The TCP H…
This article shows the TCP Header and Segment. We explain where the TCP Header and Segment are located in an Ethernet frame and also briefly view the…
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…
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…
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…
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…
The Supernetting / CIDR Chart
This articles build upon our previous pages covering what is Supernetting (Route Summarization) & How Supernets Work and Supernetting In-De…
STP/ICMP Protocols:
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…
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 3: Bridge ID, Prior…
In this article we will examine the Spanning Tree Bridge ID structure, explain why it has increments of 4096, how VLAN information is embedded (for P…
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…
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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…
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…
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…
VTP Introduction & Modes
The invention of VLANs was very much welcomed by all engineers and administrators, allowing them to extend, redesign and segment their existing network wi…
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…
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…
Distance Vector Routing Protocols
Distance Vector routing protocols use frequent broadcasts (255.255.255.255 or FF:FF:FF:FF) of their entire routing table every 30 sec. on all their interf…
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…