Network Fundamentals: Top Picks
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…
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…
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…
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…
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…
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…
Network Protocols:
The DNS Protocol - Part 4: DNS Response Message F…
The previous article covered the DNS Query message formats. In the article we analysed them in great detail and showed how various options are select…
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…
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…
IP Subnetting - Part 5: Subnetting Guidelines
There is always that day when you are called upon to provide a solution to a network problem. The number of problems that can occur in a network are…
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 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 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 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…
STP/ICMP Protocols:
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…
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 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 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…
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VLAN Security - Making the Most of VLANs
It's easy to see why virtual LANs have become extremely popular on networks of all sizes. In practical terms, multiple VLANs are pretty much the same as h…
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…
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…
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…
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…
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…
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…
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…