VPN is an acronym for Virtual Private Network, which uses public network infrastructures to provide connection or communication services for users who are travelling or in remote areas. VPN is a form of Wide Area Network (WAN) that utilizes the Internet, private networks, or service provider backbone network also known as the VPN backbone, and specialized protocols to enable users to share files, conduct video conferencing, access network resources, databases and websites. VPN is used to provide a private and secure connection for users. 
Different Types of VPN Services
There are three different types of VPN services:
- Encrypted VPN - data is encrypted to ensure that information exchange is secured from hackers.
- Tunnel-based VPN - this type of VPN uses the method of tunneling or logical channels within the providers network
- Optical Private Networks - is a high speed networking using the SDH (Synchronous Digital Hierarchy), a major transmission technology that enables easier synchronization to interconnect networks between carriers and DWDM (Dense Wavelength Division Multiplexing), a technology which allows the delivery of ten of terabits of data over a single fiber using 40 to 80 simultaneous wavelengths.
There are different types of VPN devices utilized by consumers and providers to be able to have access to VPN services. These include:
- Customer Network Devices
- Customer (C) devices— includes routers and switches set-up within the customer network. These devices have no direct connectivity to the service provider network. C devices are not aware of the VP
- Customer Edge (CE) devices— These devices are connected to the provider network and it is located at the edge of the customer network. Connection is done through the provider edge (PE) devices.
- Service Provider Devices
- Service Provider (P) devices— these are routers and switches that are not directly connected to customer networks. They are attached to the provider network. P devices are unaware of customer VPNs.
- Service Provider Edge (PE) devices— these devices are directly connected to customer networks through CE devices. They are aware of the VPN, if the devices are connected to PE-based VPNs. PE devices are classified as Provider Edge routers (PE-r),Provider Edge switches (PE-s), PE-rs allow both routing and switching
Benefits of VPN
VPN is cheaper compared with using leased lines. Individual users and organizations save money because VPN allows users to get rid of their high expenses on long-distance leased lines and telephone charges as well as support costs. VPN provides site protection from unauthorized access, independent addressing, improved performance and bandwidth.