Avaya Extension to Cellular and Off-PBX Station application types provide users with the capability to have one administered phone that supports Communication Manager features for both an office phone and one outside phone. Off-PBX Station application types allow users to receive and place office calls anywhere, any time. Application types are Extension to Cellular, Outboard Proxy SIP (OPS), Seamless Converged Communications Across Network (SCCAN), and Cellular Service Provider (CSP). Extension to Cellular extends office calls to a user’s cellular phone. CSP performs the same functions as Extension to Cellular but is sold to a user by their cellular service provider. CSP differs from Extension to Cellular only in that a user of the CSP application type cannot disable the feature. OPS is used to administer a SIP phone. SCCAN offers voice and data access from a single SCCAN handset that is integrated with a desktop phone across the corporate Wireless Local Area Network (WLAN), public Global System for Mobile communication (GSM), and cellular networks. A user can have more than one application type per station.