VPN – Virtual Private Network

VPN is one of remote access that allows you to access public network and use it to integrate in the local network.

There are two types of remote access VPN :

1. Client Initiated

Client initiated is the common use of VPN. If user’s PC want to build a VPN connection, then the PC itself trying to build a tunnel and doing encryption until the data reach to the destination safely. But, this process is still using ISP’s network. Client Initiated VPN is often use by PC to PC rely on VPN Server or VPN concentrator to the destination network.

2. NAS (Network Access Server) Initiated

NAS Initiated is not constrain user to make the tunnel, encryption, and decryption himself. This type of VPN requires user to dial-in to NAS ISP. Then, this NAS will build the tunnel to private network’s destination. Therewith, VPN connection can be build by many client anywhere because the NAS ISP is commonly available for public.

How it works?

VPN operates at layer 2 or 3 OSI Model :

• Layer 2 Frame – Ethernet.
• Layer 3 Frame – IP.

VPN is using a tunneling technology. Tunneling is responsible to handle and provide Point-to-Point connection. Exactly, the Point-to-Point connection is form by across the public network. But, this connection does not care with data packets of other people, except only attend the maker of data transportation. Usually, this technology is develop on the network with IP addressing and IP routing setting. If the communication between source and destination is not going well, then the tunnel cannot be created, and VPN cannot be made. If the tunnel already created, the Point-to-Point connection can be directly used to pass the data. This tunnel also equip with encryption system to the passing data.

These are the tunneling technologies :

• PPTP – Point-to-Point Tunneling Protocol

It allows multiprotocol traffic to be encrypted and then encapsulated in an IP header to be sent across an organization’s IP internetwork or a public IP internetwrok sucha as the internet.

• L2TP - Layer 2 Tunneling Protocol

It allows multiprotocol traffic to be encrypted and then sent over any medium that supports Point-to-Point datagram delivery.

• IPSec TM – IP Security Tunnel Mode

It allows IP packets to be encrypted and then encapsulated in an IP header to be sent across an organization’s IP internetwork or a public IP internetwork such as the internet.

References

· www.csun.edu/~vcact00f/311/termProjects/700class/VPN.ppt

· www.bojonegoro.go.id/book/tunneling_basic.php

· www.kipsaint.com/wp-content/uploads/2007/05/VPN.doc

Another Traffic Jam

Today is my 1st mid exam, Charater Building IV. In order to avoid traffic jam, I depart from home at 8.00 o’clock. Obviously, i’m still get trapped in traffic. I doubt that I can get to my university on time. I can get out from the traffic for one hour TT

But, there is another way that usually get traffic in the further. It is because the development of busway. Amazingly, there is no traffic jam right now….Wow, I’m so happy..Finally, I get to Syahdan campus at 9.45 o’clock. Fiuh..i’m almost get late. Thanks God.

Death Youth

Recently, I have heard death youth. It’s my friend’s girlfriend. She was suffering a Lupus disease (autoimmune disorder and it effects organ systems, skin, joints, and internal organs) for one week. The, she passed away.

Another case is my young brother’s friend. He had a flu and his parents gave him a herb medicine. On the next day, he got cramp and collapse at school. And, he was get into the hospital at the emergency room. The doctor said that it was because the medicine. He got toxicant by the medicine. Evidently, there is nicotine in that medicine. On the next day, he passed away.

All of them are died with the young age. Through this incidents, I realize that we never know how long we will live, when we will die, and how do we die. Maybe, it’s not the point of life. The point is what have we done during our life. And we must appreciate every days, hours, minutes, even seconds in my life. So, I will try my best to help each other and bring happiness to other people around me.