Archive for the ‘Networking’ Category

You can remotely access a Sisco IOS (Internetworking Operating System) in what is knows as an EXEC session to control a router using its CLI (Command Line Interface).

EXEC sessions are separated into a basic user EXEC level and a privileged EXEC level to run configuration and other critical commands.

Critical Cisco Router configuration commands
‘————’ is used to prefix comments in this small tutorial

Router>enable ———— enable is used to change into privileged level
Password: —————— if passwords is enabled
Router# ———————- # means we are in privileged level
Router#disable ———– switch to user EXEC level
Router>

Router>ping xxx.xxx.xxx.xxx ———— ping is supported

The show command is used to troubleshoot your Cisco router
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Idle scan or Zombie scanning as it is referred to sometimes, is the newest and stealthiest TCP scanning technique supported by the famous Nmap. What makes it quite interesting, is that an attacker can use it to scan a target and blame it on an innocent Zombie machine.
Before explaining how it can be done, let me start with a brief explanation of the Three-Way Handshake used to start TCP connections between any two computers.

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This article is for you if you have internet connection in your Windows and would like to share it with a Linux box as well. To do that your windows machine should have two network cards connected, one for the internet service and the other one to connect to your other machine or to a hub/switch if you want to share it with more computers.

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VisualRoute

Traceroute is a famous program to draw the route taken by packets from your computer to any destination you chose. It uses UDP or ICMP echo packets with TTL value of one, then continuously increase it until it reaches the destination, this way it can get time exceeded responses from every hop in the pathway.

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Hubs, Bridges, Switches and Routers are used to build networks. If you are trying to design your own LAN (Local Area Network) at home, then you probably need to know what they do and the main differences between them. I will try to cover all that in addition to some networking details to cultivate the article and provide better understanding of how the internet works. After all, always remember that the internet as you know it is nothing more than a network of networks!

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