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…
LAN Network Topologies
Network topologies can take a bit of time to understand when you're all new to this kind of cool stuff, but it's very important to fully understand t…
Network Data Transmission
Network data transmission refers to the process of sending and receiving information between two or more devices connected to a network. It is a crit…
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:
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: 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…
ML-Based Security Analytics in NetFlow Analyzer…
This article explores how machine learning (ML) and network flow telemetry can be used to establish behavioral baselines, detect anomalous asset acti…
Network Protocols:
The Supernetting / CIDR Chart
This articles build upon our previous pages covering what is Supernetting (Route Summarization) & How Supernets Work and Supernetting In-De…
Transmission Control Protocol - Part 2: Quick Ove…
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 on…
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…
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…
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…
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…
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…
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…
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 'p…
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…
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 wa…
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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 their…
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…
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…
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…
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 2: How OSPF Protocol Works & Basic Concept…
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 (N…
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…
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…