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Suggested Articles:

IP Protocol

IP Protocol - Part 3: IP Classes, Network & Hos...

This article explains the 'Network-ID' and 'Host-ID' concept found in IP addressing and subnetting. We analyse the structure of IP addresses and ne...
Spanning Tree Protocol (STP)

Spanning Tree Protocol – Part 3: Bridge ID, Pri...

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...
ICMP Protocol

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 (...
TCP - UDP Protocol Analysis

Transmission Control Protocol - Part 3: The TCP...

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 t...

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Netflow Articles:

Netflow vs SNMP. Two Different Approaches to Ne...

SNMP (Simple Network Management Protocol) and Netflow are both popular protocols with admins, prized for their ability to give visibility over the ...

Netflow: Monitor Bandwidth & Network Utilizatio...

Monitoring network traffic & bandwidth usage via Netflow is mandatory for any type and size network. Gaining visibility into user traffic, appl...

NetFlow Analyzer: Free Download, Step-by-Step I...

In our previous article we explained how a Netflow Analyzer can help you gain visibility into your user traffic, application traffic and data flows...

Complete Guide to Netflow: How Netflow & its Co...

This article will cover the basics of Netflow, including its use cases, Netflow supported devices, Netflow history, and variants. We’ll also dive i...

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VLAN Networks

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 ...
VLAN Networks

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...
VLAN Networks

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 ...
VLAN Networks

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 secur...

Routing

OSPF - Part 6: OSPF LSA Types - Purpose and Function...

Our previous article explained the purpose of Link State Update (LSU) packets and examined the Link State Advertisement (LSA) information contained with...
Routing

OSPF - Part 4: OSPF Neighbor States – OSPF Neighbor ...

This is the third article of our OSPF series which analyzes the different OSPF States routers go through during the OSPF discovery and neighbor forming ...
Routing

OSPF - Part 2: How OSPF Protocol Works & Basic Conce...

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 ...
Routing

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 a...

Cisco Routers

How To Configure Windows VPDN (PPTP) Dialup Connection

Setting up a Windows VPDN connection is a required task in order to connect to a remote network. In previous articles we covered the set up of a VPDN - ...
Windows Servers

How to Install Windows Server 2012 from USB Flash – ...

Most would remember the days we had to have a CDROM or DVDROM in order to proceed with the installation of an operating system. Today, it is very common...
Virtualization & VM Backup

How to Fix VMware ESXi Virtual Machine 'Invalid Status'

In this article, we'll show you how to deal with VMs which are reported to have an Invalid Status as shown in the screenshot below. This is a commo...
Cisco Routers

Configuring Point-to-Point GRE VPN Tunnels - Unprote...

Generic Routing Encapsulation (GRE) is a tunneling protocol developed by Cisco that allows the encapsulation of a wide variety of network layer protocol...