The reasons to deploy and use VPNs vary greatly among organizations. Cost is always a significant factor in any business decision. Budgets are never unlimited, so organizations must consider their options amid limited funds to accomplish their missions and goals. One common goal is high productivity. Granting workers the ability to access and use resources in a timely and efficient manner assists in the completion of work. When those resources are computer files or network services, employees no longer need to be in the same building as those resources. Remote access to resources, therefore, is becoming more common than ever.

Secure remote access is essential. As the proliferation of access and connectivity spreads from work to home to portable/mobile devices, access to the Internet and private LANs is becoming ubiquitous. Companies must use security controls on resource access or suffer the consequences of insecure access methods. With the removal of physical limitations for access comes the loss of control over where and how workers connect into the private LAN.

Workers may connect to the company LAN from mobile phones, through Internet cafés, over hotel networks, and at other random Wi-Fi hotspots. In this age of Bring Your Own Device (BYOD), many use personally owned laptop computers and mobile devices rather than officially issued company systems. All of these are outside the control of the company’s IT and security department. The only option is to limit LAN connections to those that can be secured. Thus, VPNs have become a necessity in this mobile and interconnected world.

VPNs support remote access from a wide variety of complex devices, reduce risk caused by insecure access locations, and enable interaction with all LAN resources. Furthermore, flexibility, scalability, ease of administration, reliability, and more make VPNs an obvious choice in the face of modern connectivity risks and challenges. Scalability is the ease of which an organization can quickly increase capacity and use or shrink capacity and use of a device, system, or network.

Remote access, mobile connectivity, and secured communications are solid reasons to deploy and use a VPN. But are these the only positive aspects of a VPN? The most often touted benefit of VPNs is cost savings. VPNs are a great way to save on long-distance charges for telecommuters and traveling workers. These also create huge savings for businesses that would need only local Internet links for a VPN, rather than a dedicated leased line between each location (FIGURE 9-5). The farther away each business location is and the more locations a company has, the more cost savings a VPN can generate. A leased line is a semi-private connection subscription whereby the traffic on the line is limited to those that have subscribed (often one to a few businesses in a geographic area). Leased lines can potentially transmit the data of business competitors, so eavesdropping on unencrypted data packets is a concern, as is the high cost of such an exclusive means of communication.

Additionally, to truly compare the connectivity that a VPN offers to dedicated leased lines, you need a full mesh of leased lines. A full mesh requires a line between each business location. This allows for direct communication between one site and another. Since a VPN across the Internet would provide the equivalent site-to-site communication capabilities, only a mesh network of dedicated leased lines can truly compare. In this leased line situation, your organization is the only entity using the communication pathway; it is dedicated for your business. This solution is obviously very expensive compared to a VPN’s significant cost savings.

As corporations seek to reduce IT infrastructure costs, a common technique is to allow employees to telecommute. Telecommuting allows workers to access corporate resources whether the employee works from home, while traveling, or while on site with a customer. In the past, telecommuting clearly implied the use of dial-up connections to connect with the company LAN; now it refers to any geographically remote employee connecting to the network to do his or her job.

With the proliferation of high-speed broadband connections and Wi-Fi, telecommuting has become more plausible and realistic. Through the use of VPNs, telecommuting enables a true remote office, rather than just a file exchange and communication system. VPNs make telecommuting not only possible, but also practical and secure. Because of VPNs, expanding the workforce is no longer a geographically limited proposition.

Extranets are often deployed as businesses establish new partnerships or seek more interaction with suppliers, distributors, and other external entities. Extranets are border networks, similar to a demilitarized zone (DMZ), where resources are hosted for access by external entities. However, unlike a DMZ, an extranet is not open for public use. Only a limited and specific set of users is allowed to connect into an extranet. Often, this limitation means that a specific VPN configuration is necessary to access the extranet’s resources. With VPNs, extranets are both possible and practical. Extranets can suffer from extensive hits or visitor traffic to the site. Consider the process of checking the delivery status of a package you ordered by logging into the carrier or delivery service’s website. That is using an extranet. You have an ability to see only the status of your specific package within the system, and the means to gain that access is with a specific tracking number.

VPNs allow system administrators to manage and control a network remotely. Because of VPNs, employees can work from anywhere, friends can create WAN links to support multiplayer games, and technical support can repair client systems remotely. A VPN is the solution whenever a network connection is needed between two systems or two networks but it is not feasible to install a direct cable connection.

Often, the real benefits of a VPN are not from the VPN itself, but from all of the new possibilities for work, research, learning, and play that are now feasible. These benefits include:

• Reduced equipment costs
• Unlimited geographic connectivity
• Increased flexibility and versatility of worker location
• Improved privacy and confidentiality due to strong encryption
• Verified transmission integrity
• Fully scalable global infrastructure and architecture
• Rapid deployment options
• Flexible integration with existing networks and technologies
• Faster return on investment (ROI) than traditional WAN infrastructures
• Reduced dependence on long-distance carrier solutions
• Reduced support burden on Internet service provider (ISP)

Individuals and organizations that use and integrate VPNs in new and unique ways are sure to reap additional benefits. History shows us that as new means of communication are created, these often change and are used in ways that were unpredictable at the beginning of the installation. However, VPNs are not perfect, and some challenging issues limit their use.