VPNs let users create their own private networks by drawing on the intelligence embedded in the carrier’s network. This intelligence is actually derived from software programs residing in various switch points throughout the network. Services and features are defined in software, giving users greater flexibility in configuring their networks than is possible with hardware-based services. In fact, an entire network can be reconfigured by changing a few parameters in a network database.

The intelligence inherent in virtual private networks lets network managers control many operating parameters and features within their communications environments. For example, the flexible-routing feature allows the network manager to reroute calls to alternate locations when a node experiences an outage or peak-hour traffic congestion. This feature is also used to extend customer service business hours across multiple time zones. The location-screening feature lets network managers define a list of numbers that cannot be called from a given VPN location. This helps contain call costs by disallowing certain types of outbound calls.

Originating call screening is a feature that gives network managers the means to create caller groups and screening groups. Caller groups identify individual users who have similar call restrictions, and screening groups identify particular telephone numbers that are allowed or blocked for each caller. Time intervals are also used as a call-screening mechanism, allowing or blocking calls according to time-of-day and day-of-week parameters.

With a feature called NNX sharing, VPN customers reuse NNXs (i.e., exchange numbers) at different network locations to set up their seven-digit on-net numbering plans. This provides dialing consistency across multiple corporate locations. Another feature, partitioned database management, lets corporations add subsidiaries to the VPN network while providing for flexible, autonomous management when required by the subsidiaries to address local needs. The VPN can even transparently interface with the company’s private network or with the private network of a strategic partner. In this case, the VPN caller is not aware that the dialed number is a VPN or private network location, because the numbering plan is uniform across both networks.

VPNs provide several other useful features, including ANI data, which is matched to information in a database containing the computer and telecommunications assets assigned to each employee, for example. When a call comes through to the corporate help desk, the ANI data is sent to a host, where it is matched with the employee’s file. The help desk operator then has all relevant data available immediately to assist the caller in resolving the problem.