Network Fundamentals: Top Picks
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…
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…
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…
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…
Featured Subcategories:
Netflow Articles:
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…
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 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:
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…
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…
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…
Transmission Control Protocol - Part 4: In-Depth…
This article is an introduction to the 7-page TCP Header analysis section that follows. We briefly view each section of the TCP Header and then move…
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…
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 Subnetting - Part 2: Subnet Masks & Their Effe…
There are a few different ways to approach subnetting and it can get confusing because of the complexity of some subnets and the flexibility they off…
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…
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…
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…
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…
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…
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…
Static VLANs
VLANs are usually created by the network administrator, assigning each port of every switch to a VLAN. Depending on the network infrastructure and securit…
VLAN Tagging - Understanding VLANs Ethernet Frames
We mentioned that Trunk Links are designed to pass frames (packets) from all VLANs, allowing us to connect multiple switches together and independently co…
OSPF - Part 3: OSPF Adjacency & Neighbor Forming Proce…
This is the thrid article of our 6-part OSPF series (see below) that describes how OSPF routers perform neighbor relationship and adjacency. We’ll examine…
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…
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…