Suggested Articles:
Ethernet Protocol, CSMA/CD, Collisions
Troubleshooting techniques for Fast Ethernet
This page will primarily discuss problems unique to Fast Ethernet.
The Collision Domain
Incompatible Ethernet Jabber
Auto-negotiation Priorities…
Network Cabling
Serial Direct Cable Connection, DB9, DB25, COM Po…
This article covers the popular serial ports on workstations, servers and laptop computers. We cover serial data transfer, port pinouts, port speeds…
Network Address Translation - NAT
Static NAT - Part 2
The previous page (Static NAT - Part 1) helped us understand what exactly happens with Static NAT and how it works, and we saw a few examples of how…
Ethernet Protocol, CSMA/CD, Collisions
Ethernet Troubleshooting - Physical Frame Corrupt…
When troubleshooting your Ethernet network, the first thing to look for is physical frame corruption. In this essay, we will discuss the different ca…
Featured Subcategories:
Netflow Articles:
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…
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: 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…
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…
Wi-Fi Key Generator
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Cisco Password Crack
Decrypt Cisco Type-7 Passwords on the fly!
VLAN Networks
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…
VLAN Networks
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 Networks
VLAN InterSwitch Link (ISL) Protocol Analysis
Deciding whether to use ISL or IEEE 802.1q to power your trunk links can be quite confusing if you cannot identify the advantages and disadvantages of eac…
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…
Routing
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…
Routing
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
OSPF - Part 5: Analysis of OSPF Link State Update (LSU…
This article explains how OSPF uses Link State Advertisement (LSA) to exchange information about the network topology between routers. When a router recei…
Routing
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…
Virtualization & VM Backup
Understanding Deduplication. Complete Guide to Dedupli…
When considering your VM backup solution, key features such as deduplication are incredibly important. This is not simply from a cost perspective but also…
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 - PP…
Cisco Firewalls
Understand & Configure NAT Reflection, NAT Loopback, H…
This article examines the concept of NAT Reflection, also known as NAT Loopback or Hairpinning, and shows how to configure a Cisco ASA Firewall running AS…
Cisco Routers
How To Configure DNS Server On A Cisco Router
The DNS protocol is used to resolve FQDN (Fully Qualified Domain Names) to IP addresses around the world. This allows us to successfully find and connect…







