Network Fundamentals: Top Picks
DoS & DDoS Attacks
A Denial of Service (DoS) attack is a malicious attempt to disrupt the normal functioning of a website, server or network by flooding it with traffic…
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…
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…
Power over Ethernet - Understanding PoE Technolog…
Power over Ethernet (PoE) was invented by PowerDsine back in 1997 and the first power injector (Midspan) was installed in 1998! Many manufacturespart…
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Netflow Articles:
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…
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:
IP Protocol - Part 2: The Internet Protocol (IP)…
This article examines the Internet Protocol (IP) and its position within the OSI Model. We take a look at the IP Header and all fields contained with…
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…
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…
Supernetting In-Depth Analysis - Learn to Identif…
Our previous article served as an introduction to Supernetting, also known as Route Summarization. We covered the concept of Supernetting, how it wor…
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 mi…
TCP Header Anaylsis - Section 1: TCP Source & Des…
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 specify…
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…
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…
STP/ICMP Protocols:
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 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 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…
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…
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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…
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 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 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…
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…
Hybrid Routing Protocols - Advantages and Disadvantage…
Hybrid routing protocols are a combination of distance-vector and link-state routing protocols, and are used to provide a more efficient and scalabl…
OSPF - Part 1: Introduction, OSPF Packet Structure, OS…
Open Shortest Path First (OSPF) is a popular routing protocol developed for Internet Protocol (IP) networks by the Interior Gateway Protocol (IGP) working…
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…