Network Fundamentals: Top Picks
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…
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…
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 criti…
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 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…
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 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…
Network Protocols:
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…
UDP Protocol - Header
This article covers the UDP protocol. We examine the structure of the UDP header, the protocols that use UDP as a transport plus a lot more.
Some co…
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…
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…
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 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…
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…
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…
STP/ICMP Protocols:
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…
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…
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 - 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…
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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…
VLANs - Access & Trunk Links
If you've read our previous article The VLAN Concept - Introduction to VLANs then you should feel comfortable with terms such as 'VLAN', 'Stati…
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…
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…
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…
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…
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…
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…