Virtual Private Network (VPN) Technology

The proliferation of network users, accessibility, flexibility, and cost effectiveness of Wide Area Network (WAN)/Internet connections have increased the need for affordable and secure communications. Virtual Private Network (VPN) technology has become a preferred technology due to the security levels it provides during transmission of data.

VPN Networks are primarily extended private networks comprising links across a shared public telecommunication infrastructure such as the Internet. In a VPN system, data is transmitted between two computers over the public network emulating a point-to-point link. Data packets are encrypted at the sending end and decrypted at the receiving end. Due to the encryption and authentication of IP packets sent over VPN networks, the data even if intercepted, is impossible for hackers to decipher without the encryption keys. VPN technologies maintain security and privacy through using tunneling protocols and security procedures. In VPN networking, VPN LAN can take up various forms by combining different hardware and software technologies. VPN LANs are those connections between a remote local area network (LAN) and a private network. VPN systems work in multiple environments and related technology to render secure solutions.

The tunneling protocol, also called Encapsulation protocol is a network technology that includes establishing and maintaining a logical network connection. The most widely used VPN tunneling protocols are, Layer Two Tunneling Protocol (L2TP), IP Security (IP Sec), Point-to-Point Tunneling Protocol (PPTP), Secure Sockets Layer/Transport Layer Security (SSL/TS), Open VPN, Layer 2 Tunneling Protocol version 3 (L2TPv3), VPN Quarantine, and Multi Path Virtual Private Network (MPVPN). VPN technology supports two types of tunneling – voluntary tunneling, where the VPN connection set up is managed by VPN client, and compulsory tunneling, where the VPN connection set up is managed by the network provider. In tunneling, data packets are encapsulated within IP packets and then transmitted across the Internet. On reception of data at the receiving network end, the encapsulated packet is stripped from the IP packet in order to obtain the original message packet.

Trusted VPNs and Secure VPNs are two major VPN technologies that secure and improve VPN performance. While Secure VPNs utilize cryptographic tunneling, trusted VPN networks depend only on the single provider’s network traffic to protect data. Trusted VPNs comprise Multi-Protocol Label Switching (MPLS), a technology that is frequently used to overlay VPNs with Quality of Service (QoS) across a trusted delivery network, and Layer 2 tunneling protocol, which takes on the characteristics of two proprietary VPN protocols.

Cryptographic tunneling protocols are used by secure VPNs to provide privacy to networks through encryption, authentication, and message integrity. In this advanced technique, there are options to block snooping through packet sniffing, block spoofing of identity and altering of messages. By implementing and operating the right secure VPN protocols it is possible to provide secure communications over insecure networks and considerably improve VPN performance.

The popular VPN tunneling protocols are Internet Protocol Security (IPSec), ?Point-to-Point Tunneling Protocol (PPTP), and ?Layer2 Tunneling Protocol (L2TP). Internet Protocol Security (IPSec) is a widely used and standardized VPN protocol that is most preferred due to its interoperability benefits. IPSec is an open standards framework consisting secure protocol suite that can be run on an existing IP connection. This VPN protocol operates at layer 3 of the OSI model. It provides data authentication and encryption, and can be implemented on any device communicating over IP. IPSec protects all data traffic carried over by IP. It also provides encryption and authentication for non-IP traffic by concurrently operating with Layer 2 tunneling protocols. The three major components incorporated in IPSec are: Authentication Header (AH), Encapsulating Security Payload (ESP), and Internet Key Exchange (IKE). The authentication header that is added after the IP header provides authentication at the packet level, and ensures that the data packets are not meddled with along the route. ESP gives confidentiality and authentication of data origin.

Point-to-Point Tunneling Protocol (PPTP) is Microsoft’s proprietary development that is used in VPN Networking and communications. It authenticates users through employing authentication protocols (MS-CHAP, CHAP, SPAP, and PAP). Although PPTP has ease of use, it is still not very flexible solution and is not interoperable like other VPN protocols. The communication types of PPTP are: PPTP connection (PPP link is established to an ISP by the client), PPTP control connection (PPTP connection to the server is created by the user), and PPTP data tunnel (communication is exchanged between client and server within an encrypted tunnel). PPTP is generally employed to secure communication channels between many Windows hosts on the internal network.

The Layer 2 Tunneling Protocol (L2TP) tunnels Point-to-Point protocol (PPP) across a public IP network. It operates on layer 2, enabling non-IP protocols to be transported through the VPN tunnel and also works on Layer 2 components such as ATM, frame relay, etc. L2TP can provide encryption service in conjunction with other protocols or encryption mechanisms.

Technological advancements have made businesses to look for enhancements to secure their networks and business communications. In the line of VPN technology, there is an influx of VPN products that occupy the marketplace. Customer compare VPN products based on functionality and flexibility and employ the best of technology. VPN comparison or even comparison of technological products would open a wide array of choices to select. It depends on the set of requirements of the customer to match with the appropriate technology gadgets for effective use.