Cisco offers a wide variety of connectivity, expansion and upgrade modules to accommodate the range of application needs in customer networks. The network modules assure customers that they can choose a connectivity solution that fits their requirements. As modular components, they are easily and inexpensively field-upgradeable as customer requirements change.??The WS-X4013 supervisor engine is used in the Catalyst 4006 switch. This supervisor engine provides data path and data control for all network interfaces.