VPN – What is VPN and how it works?

A VPN (virtual private network) offers network connection possibility over an extensive physical distance (remoteness). But you need to know that it can work over both on private networks and public networks (Internet).

VPN in simple words make possible for clients or whole LAN-s on other side of the internet to connect into main LAN pesmises and have the “technical impression” that they are localy connected to this site. This includes gaining the local IP address from local DHCP pool, possibility to use all the LAN resources that are defined by the administrator etc.

Features shows that the VPN is a type of WAN (wide area network). The purpose of its use in network is: file sharing, video conferencing and facilitating from other similar network services. Though, such services are available already in other alternative mechanisms and technologies, but use of a VPN is made for getting more efficiency of available remote resources, sharing data and better communicating. Most of all, this technology can be implemented in relatively a low cost.

Technologies working at the back of VPN

A number of network protocols like: PPTP, L2TP, IPsec and SOCKS can be employed in the mechanism of a VPN. The presence of such protocols in the VPN is necessary to carry out the processes of authentication (verification of users) and encryption (to hide sensitive data from the other online public).

Tunneling:

With the help of tunneling, a VPN can use existing hardware infrastructure on the Internet or intranet. Three different modes of VPN are possible for the following purposes: remote client’s connections over internet, LAN-to-LAN internetworks and for restricted access inside an intranet.

VPNs for distant Connectivity over the Internet

To increase the mobility of any organization’s workers and to be connected to the company’s networks, a VPN deployment can be a good solution. This device can be employed to handle such circumstances of distance and in order to get protected access to those offices of organization, connected over the Internet. But according to the client/server environment, a client (remote user) is required to log on first to his/her ISP (internet service provider) in this process of getting access to company network. Then company’s VPN server connection is required.

Once connection is established between the remote client and server, the communication process will begin soon after this with the internal company systems over the Internet in the same way as a local host can do. Cisco VPN client can be employed for decidedly protected connectivity. And with these devices, encrypted tunneling is established for the remote employees.

VPN Extended network

It is the quality of a virtual private network to link together two networks for remote access. Moreover, in such cases of operation, the united remote network (combination of two remote networks) can further be linked to another company’s network. This kind of networking structure (extended network) is possible with a VPN server plus this VPN server’s connection.

After reviewing the payback that is attached with a VPN networking, downloading Cisco VPN client can be the desire of any organization. But certain system requirements should be fulfilled in order to get benefits from such networks like:

• Windows 98 or newer MS operating system, Mac OS X, Linux OS or Solaris Unix OS

• VPN (Cisco) client must be compatible with the VPN (Cisco) servers: VPN 3000 series concentrator 3.0 software or later and IOS Software 12.2(8)T or later etc
• PPTP, L2TP/IPsec, L2TP or any other VPN tunneling protocol