Let's take a look at the various solutions and how they apply to different environments.
There are two types of VPN technologies used on the Internet today: the trusted VPN and the secure VPN. Trusted VPNs are provisioned and managed by Internet service providers by defining paths through their networks to ensure that customers' traffic is routed over a trusted path. A customer might choose a trusted VPN because there is no equipment to buy, it's completely managed by the service provider and thus requires no maintenance, and they often include service-level agreements. Typically, trusted VPNs are less expensive upfront but more expensive over time.
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