VCN

virtual circuit number

A 12-bit field in an X.25 packet level protocol (PLP) header that identifies an X.25 virtual circuit. VCN allows data communications equipment (DCE) to determine how to route a packet through the X.25 network. VCN is sometimes called logical channel identifier (LCI) or logical channel number (LCN). Sometimes called LCI (logical channel identifier) or LCN (logical channel number).