The VPI is a value carried in the header of an ATM cell. Cells with the same value of VPI are carried in the same Virtual Path . source: EU-P103 domain: General acronyms: VPI usage: EU-P103

The more global portion (mathematically "more significant") portion of the identifier of the virtual circuit number in the ATM header. Click here to view a diagram.

As an ATM term, it is an eight-bit field in the ATM cell header which indicates the virtual path over which the cell should be routed.

See virtual channel identifier (VCI).

A section of the ATM cell header that contains the virtual path address over which the cell is to be routed.

The identifier code used with the virtual circuit identifier for routing ATM cells.

See VPI.

Virtual Path Identifier refers to an 8-bit (user to network packets) or 12-bit (network-network packets) field within the header of an Asynchronous Transfer Mode packet. The VPI, together with the VCI (Virtual Circuit Identifier) is used to identify the next destination of a cell as it passes through a series of ATM switches on its way to its destination. VPI is useful to reduce the switching table for some Virtual Circuits which have common path.