Thursday, October 21, 2010


In this post i am going to share some thought which i thought should work but it didn't....

Earlier in my previous post, i have talked about local peer-to-peer connection and transferring of files directly rather than going through the internet. At that point i talked about skype. So i thought of some idea why not to share files as torrent files created and anyone on local network who wants that file can simply add that torrent and due to local peer connection, the transfer will take at a much faster rate and if a file is of say 30 MB, then it would be copied in a minute in a general scenario if we are having a LAN of 100 MBps.

So i created a torrent of a file and tried to download it from some othe PC on the LAN, but to my surprise, it went the other way. I got connected on LAN but the transfer rate was still very slow as in case of normal download from web.

Here is the pic of the server... you can clearly see the name of my machine trying to download the torrent. So name resolution has taken place... and i am connected locally...

The picture below is the picture of the client machine on which i was trying to download the stuff.. You can easily see the Server's IP 190.168.7. 45 . Also the transfer rate taking place....

Of all this trouble, i found out one interesting thing......

Once you are connected locally, then even if your internet goes off, the download still does not stops till you are connected locally with each other.

Here in my Hostel, many students are trying to download the same reality show and this sometimes makes them connected to each other locally as one of the peers and so transfer among them takes place.....

At end, thanks for your pacience for reading my post....  :)

Rahul Sharma

Sunday, October 3, 2010

Internet Sharing by one LAN Card.... A new Discovery (For AITians)

Today i am going to describe the steps which i took to solve one of the biggest problem for me, how to make Internet server virtualized so that anyone can be server.

Lets first understand the problem statement....

Internet connection sharing is done by using one dedicated server which runs on continuously. So a person who decides to be server, has to face problems to continuously run his computer for hours. If the server needs to be shifted, then we have to shift the cable connection, move the extra LAN card to the new PC and it takes time too.
I have minimized his burden by virtualizing the server and thus anyone can be server without any problem. I have eliminated the need of extra LAN card thus sharing and receiving internet through same NIC. Thus if the computer sharing internet shuts down, then another person can share the net from his own computer within 2 minutes.

So what forced me to think in this way???

I saw the network utilization andfound that for maximum time, the utilization of 100mbps LAN Card is just 0.2-0.4% which is just the wastage of network.
Also the extra LAN card which we are using for the internet purpose, that too uses 600kbps speed internet which is negligible as compared to its capability. So why not to eliminate the extra LAN card and use the same LAN card for both the purposes.

I used the virtualization technology provided by the vmware workstation software to solve this problem.
I first created a virtual machine running windows XP which is going to be used for the server purpose…
Now instead of using physical lan card, I installed two virtual lan cards onto the virtual machine.
Now I installed all the softwares required onto the virtual machine.

Now the Input from the Modem is added to the HUB. Now one connection from the HUB runs to the computer which is going to share the internet…
Since I have kept the virtual network adapters of the virtual machine to be in bridged connection, so the machine appears as an individual machine on the LAN.

Now one of the network adapter is set to be getting its IPv4 address dynamically from the DHCP server of the internet providing company.
The other adapter is assigned the IP address which the users are going to use as the address of the server.
Now this simple machine can be copied and stored somewhere so that if sometime, something goes wrong, then the faulty machine can be deleted and the new one can be simply copied at its location.

Also now this machine can be distributed to all the clients. So if at some time the client sharing the internet shuts down his PC, even then the other user can simply switch on that virtual machine and share the internet.
Thus the burden of continuously keeping the machine in the running state is reduced.

Also the burden of extra LAN card on the machine is reduced, electricity consumption is reduced…

People Affected
1. Hostel students.
2. College Departments.
3. Network Administrators.
4. People using internet by sharing among themselves.
I hope you will like this post....... If you have any doubts or queries, you can ask me at any time....
I would also like to thank my friend Manjit for helping me to try out this idea on his server otherwise it would have remained as an idea only with no practical implementation...


Saturday, October 2, 2010


working on my computer today, i found a nice thing. The concept relates to the local peer resolution and connection among one another as local peers. I was chatting with one of my friend on LAN and i shut down the server. But still the connection among us on the chat was not broken. We were able to chat with each other, listen to one another through speakers and could send files . Also i tried to send a 4 mb file to my friend and it took less than a second to be downloaded by my fellow friend.

Why this happened???

Actually we got connected as local peers as we were on the same LAN and the Internet connection was coming from the HUB which distributed the packets to all and so we got connected on the local area network....

We needed internet to resolve our addresses, and once it resolved, we were able to communicate with each other without having internet connection also.   :)