Extranets can be set up in a number of ways. Many companies use an external website to maintain their internal resources, which they can then give their partners or external employees access to. In most cases, this option means the system is maintained by an external Software as a Service provider, who is responsible for maintaining the network and ensuring updates are applied when necessary. It also allows a great deal of flexibility in terms of access rights and the location of employees and other users. For an internally stored resource, such as a local server, companies can also set up a Virtual Private Network (VPN). This provides an encrypted connection to your internal resources, allowing external users access from anywhere, even over public Internet. With this configuration, the company maintains their resources and can set their own access rights and restrictions. There are also services available that can extend an internal network across multiple sites, allowing companies with more than one location to share resources across their entire organization.