Suggested Articles:
The OSI Model
The OSI Model: Layer 5 - Session Layer
The Session layer is responsible for setting up, managing and then tearing down sessions between Presentation layer entities. The Session layer also…
Ethernet Protocol, CSMA/CD, Collisions
Propagation Delay
You may know that the minimum frame size in an Ethernet network is 64 bytes or 512 bits, including the 32 bit CRC. You may also know that the maximum…
The OSI Model
The OSI Model: Layer 3 - Network Layer
The Network layer is responsible for routing through an internetwork and for networking addressing. This means that the Network layer is responsible…
TCP - UDP Protocol Analysis
TCP Header Anaylsis - Section 3: TCP Header Lengt…
The third field under close examination is the TCP Header length. There really isn't that much to say about the Header length other than to explain w…
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Netflow Articles:
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…
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…
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VLAN Networks
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…
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 co…
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 h…
VLAN Networks
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…
Routing
OSPF - Part 6: OSPF LSA Types - Purpose and Function o…
Our previous article explained the purpose of Link State Update (LSU) packets and examined the Link State Advertisement (LSA) information contained within…
Routing
OSPF - Part 4: OSPF Neighbor States – OSPF Neighbor Fo…
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 pr…
Routing
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…
Routing
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…
Cisco Routers
Cisco Router PPP Multilink Setup and Configuration
This article provides an in-depth explanation of PPP Multilink and shows how to configure a Cisco router to use PPP Multilink between two serial interface…
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 common…
Virtualization & VM Backup
How to Enable SNMP on VMware ESXi Host & Configure ESX…
In this article we will show you how to enable SNMP on your VMware ESXi host, configure SNMP Community string and configure your ESXi firewall to allow or…
Network Protocol Analyzers
How to Reconstruct HTTP Packets/Data & Monitor HTTP Us…
HTTP reconstruction is an advanced network security feature offered by nChronos version 4.3.0 and later. nChronos is a Network Forensic Analysis applicati…







