Appendix E: Virtual Private Networking

E.1 What is a VPN?

A Virtual Private Network (VPN) is a shared network where private data is segmented from other traffic so that only the intended recipient has access. It allows organizations to securely transmit data over a public medium like the Internet. VPNs utilize tunnels, which allow data to be safely delivered to the intended recipient.

Because private networks lack data security, IPSec-based VPNs employ encryption technologies that protect a private network from data theft or tampering. These private networks can be implemented over any type of IP network, which allows for excellent flexibility.

E.1.1 VPN Applications

VPNs are traditionally used three ways:

-Extranets: Extranets are secure connections between two or more organizations. IPSec-based VPNs are ideal for extranet connections, as they can be quickly and inexpensively installed. Extranets are often used to securely share a company’s information with suppliers, vendors, customers, or other businesses.

-Intranets: Intranets are private networks that connect an organization’s locations together. These locations range from a headquarters, to branch offices, to a remote employee’s home. Intranets are often used for email and for sharing applications and files. A firewall protects Intranets from unauthorized access.

-Remote Access: Remote access enables mobile workers to access email and business applications. Remote access VPNs greatly reduce expenses by enabling mobile workers to dial a local Internet connection and then set up a secure IPSec-based VPN communications to their organization.

E.2 What is IPSec?

Internet Protocol Security (IPSec) is a set of protocols and algorithms that provide

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Billion Electric Company BiGuard 50G user manual What is a VPN?, VPN Applications, What is IPSec?