Is it true?
Is it possible to access a Web page from anywhere in the world? You
will now say, ‘YES’. Now another question. Is it possible to access
resources in the your network from anywhere in the world? You are in a foreign
country and you need some information that you have in your network far
here in India. How nice it is if you can log in just like into the Web and
access it from there. It is possible with the Virtual Private Networks that is gradually
gaining roots.
What is VPN?
A Virtual Private Network (VPN) in simple terms is the use of a public
network for private use. In other words, it is a network that uses a
public network service (Internet) as the backbone of its Wide Area
Network. Pay the service provider (ISP) and your headache is over. A VPN
digs out a way, rather a private passage for the company network through
the Internet.
Problems
Of course VPNs are appealing at the very outset. However there are very evident problems that
might prevent one from opting a VPN. Here are a few of them.
- Security
Your network has crucial
data in it. Naturally the doubt would be whether the data is safe and
secure, once it is accessed through a VPN. Many security protocols are
emerging, which might prove all the existing fears to be wrong.
- Bandwidth problems
We spend so much of time
idle in front of the system for a web page to download. There is not
enough bandwidth. Then how is it that you can be assured that you can
access the required resources when and where you need? Service providers
are trying to find out ways to do this. Maybe they can strictly manage the
available bandwidth and prioritize the usage.
Reliability of the
Internet
Is the Internet reliable?
Not always. While the Internet backbone is pretty robust, ISP gateways do
fail occasionally and these can make your VPN a better dream than a
reality.
VPN tunneling technology
How is the data carried
from one point to another through the Internet? It uses the tunneling
technology.
Tunneling, also known as
encapsulation enables a network to send its data via another network’s
connection. Here a network protocol is encapsulated within packets carried
by a second network.
VPNs can send data in two
ways.
Encapsulation
It is simply bundling one protocol into
another. As you all know, Internet uses TCP/IP. So the VPN data is
encapsulated to TCP/IP. However this method does not guarantee proper
security of your data. So it is not widely used.
Encrypted encapsulation
Before being sent, the
packets are encrypted so that the data is unreadable to outsiders. These
packets now travel through the Internet to the destination. Once it
reaches the destination, the packets are changed to their original format.
Only those who have authorization to contact the server can retrieve the
data.
Models of tunneling
There are two models, of
tunneling
- Client initiated
To connect to the VPN
server, here the client has to dial to the local ISP using the respective
VPN client. Depending upon the tunneling protocol being used, the client
will have to go through an authentication process.
- Client-transparent
tunneling
Here the tunnel-enabled
server (the server dedicated for VPN connectivity that the ISP has) has
dedicated connectivity with VPN servers of various companies. When needed,
the clients connect to the local ISP and access this server. After
authentication, the clients are directed to their respective VPN servers.
They have to cross the company’s security gateway to login.
Tunneling protocols
The major fear that holds
back network managers from going in for VPN would be the security factor.
The prominent players in the field of VPN know this and are coming out
with new and new tunneling protocols, which they say will safeguard data.
Among the prominent ones are the Point to Point Tunneling Protocol (PPTP)
developed by Microsoft and the Layer 2 Forwarding (L2F) developed by Cisco.
There is the Internet Protocol Security(IPSec) which provides secure
communications transparency. It is a standard chosen by the Internet
Engineering Task Force(IETF). Microsoft and Cisco with IETF are in an
attempt to merge this protocols into a standard called Layer 2 Tunneling
Protocol(L2P2).
Benefits of VPNs |
- The network can be accessed from anywhere across the globe. So those who are traveling will find it very helpful. - Once you log in to the network from - VPNs are flexible. They can be used to - VPNs help the companies to reduce cost. |
Virtual Private Networks
Access your company's network resources
from anywhere in the world
VPNs in easy steps
Use NT to connect your company’s multi-location networks over the
Internet
VPN source page
A one-stop source for VPN Information. An educational resource for anyone
interested in virtual private networks.
What is Virtual Private
Networking
What can you do if you just want to give
company insiders and a few select business partners and customers easy and
relatively secure remote access to company data via the Internet? You can
set up a virtual private network.
A virtual private affair
Virtual private networks offer some serious savings -- if you know the
secret.