How to run multiple computers from single CPU

Hi everyone,
A 100….!!! CELEBRATING A 100 blogs … wooohoooo , I cannot believe I am typing my 100th blog post! Wow my little blog has come so far and I thank you all so much for continuing  to stop by! Without all of the support, comments, shares, hits, everything I wouldn’t have kept Crazylearner going so I thank you!

Today i will show you how can run multiple computers from single CPU. I mean how can you run multiple workstations from single CPU.

You must have heard about desktop virtualization ? If not, i’ll tell you about it all what i know.

There are many approaches to virtualization
Most virtualization technologies are expensive to acquire, implement, and maintain. NComputing is different because we save you money from day one. This desktop virtualization technology allows up to 100 users to simultaneously use a single computer—at a very low cost. I looked for it and came to conclusion that this is one of the best thing which i have came to known recently in computer field.

so what is desktop virtualization? In simple terms it is sharing the power of single cpu with multiple users .It appears to each of the user that he is using his own complete setup including processor .This technology is not new but its availability to general public is certainly new.

Here is simple example to understand how to set up desktop virtualization.

what you are going to need if you don’t want to use desktop virtualization.

11 monitors,11 speakers ,11 keyboards, 11 mouse and 11 cpu

what you are going to need if you want to use desktop virtualization

11 monitors,11 speakers ,11 keyboards, 11 mouse, 1 cpu and 2 desktop virtualization kits (a kit comes with software and hardware and can support 5 users.)

How to run multiple computers from single CPU
How to run multiple computers from single CPU

Advantage of running multiple computers from single cpu

You are saving the maintenance and power cost of 10 CPUs.

Typically a user is able to utilize only 10 % of available CPU power . This one kit uses approx 70 % of cpu power among 6 users including the host.

Currently the company which is providing this kit is Ncomputing. For more information and processing related issues visit product guide.

There are various models available as we go for Ncomputing. i will share all the information regarding every model with specification.

Here is a video which explains in details

How to bye pass Firewall

How to bye pass Firewall

To bye pass the Firewall you must know the firewall identification means full information about Firewall like type , version , and rules of almost every firewall on a Network.

How to bye pass Firewall
How to bye pass Firewall

These are three technique for Firewall Identification


  • Port scanning
  • Firewalking
  • Banner grabbing

Port Scanning (How to bye pass Firewall)

Some firewalls have obvious signatures
  • Check Point’s FireWall-1 listens on TCP ports 256, 257, 258, and 259
  • Check Point NG listens on TCP ports 18210, 18211, 18186, 18190, 18191, and 18192 as well
  • Microsoft’s Proxy Server usually listens on TCP ports 1080 and 1745

Here we are providing you , the ways by which you can conceal your Scanning

  • Randomize target ports
  • Randomize target addresses
  • Randomize source ports
  • Distributed source scans
  • Using multiple computers on the Internet, each taking a small portion of the scanning targets
These techniques will fool most IDS systems with default rules.
And here are the Countermeasure of above
  • Block unneeded ICMP packets at your border router
  • Use an Intrusion Detection System, such as Snort
  • IPPL is a Linux daemon that detects port scans (link Ch 901)
  • Cisco routers have ACL rules to block scans

Firewalking (How to bye pass Firewall)

Firewalking is a method to collect information from remote network that are behind firewalls. Firewalk Looks Through a  Firewall

How to bye pass Firewall
How to bye pass Firewall
 In above figure  , Suppose The target is Router3
We want to know which ports Router3 blocks, and which ports it allows through.
Phase 1: Hopcount Ramping
  1. First Firewalk sends out a series of packets towards the destination with TTL=1, 2, 3, …
  2. When the target (Router3) is reached, that determines the TTL for the next phase
  3. In this example, the Target is at TTL=3, so all future packets will use TTL=4


Phase 2: Firewalking

  1. TCP or UDP paclets are sent from the scanning host to the Destination
  2. They all have TTL=4

Firwalking Countermesure

  • You can block “ICMP TTL expired” packets at the gateway
  • But this may negatively affect its performance
  • Because legitimate clients connecting will never know what happened to their connection

Banner Grabbing

Banner are messages sent out by network services while connecting to the service.They announce which service is running on System

Banner grabbing is simple method of OS detection, its also help to find services runs by Firewall. there are three measure services send out through it is TELNET , FTP and Web Server.

Banner Grabbing Countermeasures

  • Eliminate the open port on your firewall
– A management port should not be open externally anyway
  • If you must leave the ports open on the external interface of your firewall
–Change the banner to display a legal warning reminding the offender that all attempts to connect will be logged

How to bye pass Firewall

Breaching  Firewall

Byepassing a firewall using HTTP Tunnel

Placing Backdoors through Firewall

Hiding behind a Covert channel : Loki

The above topic and tools to bye pass firewall cover in next post as How to bye pass Firewall 2