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IP address is a numeric identifier that is assigned to a device for communicate with other devices on a network. IP address consists of four decimal numbers which are separated by dots or decimal points. Hence, we call dotted-decimal notation. For example, 192.168.0.1 is an IP address written in dotted-decimal notation, but the binary version is 11000000 10101000 00000000 00000001 (IP address is stored as binary numbers). You will see how to convert between binary and decimal numbers later.

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Introduction

This post shows how to change MAC Address in Windows by edit Windows Registry. Before you read this post, I suggest you to read Change MAC Address in Windows, Part I: Introduction first. Also, if you haven’t try to change MAC Address by using feature on a NIC, I recommend to try it before on Part II: Feature on NIC.

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Introduction

Before you read this post, I suggest you to read Change MAC Address in Windows, Part I: Introduction first.

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Introduction

MAC Address (Media Access Control) or physical address is a unique address assigned to NICs (Network Interface Card) by the manufacturer for identification. Even though MAC Address is a unique address which means that there shouldn’t be any MAC Address duplication occur in the world. But do you know that you can still change the MAC Address of NICs which is called MAC spoofing. It is a technique of hacking which you change the MAC Address to bypass access control lists on firewalls or routers.

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This topic separates into 2 posts:

1. Secure the Network using Cisco Port Security, Part I: Concept
2. Secure the Network using Cisco Port Security, Part II: Configuration

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This topic separates into 2 posts:

1. Secure the Network using Cisco Port Security, Part I: Concept
2. Secure the Network using Cisco Port Security, Part II: Configuration

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Introduction

If you need to connect more than one switch and going to have more than one VLAN, you need to configure trunk port in order to send traffic between switches. Below shows how to set trunk port (802.1Q) on 3Com Switch 3300XM.

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Introduction

Backup hardware’s configuration is the one important routine for network engineers so that when the hardware break down you can recover the failed system within an acceptable time. To backup the configuration, one effective way is to use TFTP to backup and restore configuration between remote hosts.
In the example below, I’ll show how to backup and restore configurations between TFTP Server and Cisco’s router. The TFTP Server will use Cisco TFTP Server software.

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When you know IP address and mask number, you sometimes want to know subnet number, subnet broadcast address and range of valid IP addresses. In common ways, you can find these by convert the IP address with mask number to binary and perform boolean AND but that takes too much time. So let see how to find these answers in a short time.

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