The primary benefits derived from implementing VPN over traditional leased line networks
VPN eliminate the needs for expensive long-distance leased lines. What a corporate require was only a relatively short dedicated connection to the service provider. The connection can be either a local broadband connection such as DSL service or a local leased line. Both of the stated connection are much cheaper than a long-distance leased lines. Service providers can in theory charge much less for their support than it costs a company internally because the public provider’s cost is shared amongst potentially thousands of customers.
Elements of cost reduction also include transport media, bandwidth, backbone equipment, and operations. According to industry research, site-to-site connectivity costs are typically reduced by average 30% over domestic leased line networks. Cost reduction for client to site dial access is even greater, in the 60%-80% range.
Instead of owning and operating a private network infrastructure, company may outsource some or all of their wide area networking functions to a service provider. By doing so, the cost of management and upkeep of the network setup can be reduced substantially. Not only that, it also enables company to focus on core business objectives, instead of managing a WAN or dial access network.
The cost of using traditional leased lines may be reasonable at the beginning stage, but as the the organization grows the number of leased lines required increases exponentially as more branches must be added to the network. With VPN, company can just tap into the geographically-distributed access already available, which is limited in the case of a traditional leased lines.