Abstract: A method is described for controlling customer installations of software or data by providing to the customer an encrypted list of authorized installation targets, whereby the installation program reads and decrypts the list, and only allows installation to proceed if the customer's installation target has a serial number that matches one of the vendor-provided serial numbers in the authorization list. Provision is also made for allowing customers to add serial numbers to the list, within constraints predetermined by the software vendor. Also provided is a method for a customer to perform a predetermined number of installations, whereby the software maintains and decrements a counter in an encrypted file on a storage medium, keeping track of how many remaining installations a customer may perform.

Abstract: A method is described for controlling customer installations of software or data by providing to the customer an encrypted list of authorized installation targets, whereby the installation program reads and decrypts the list, and only allows installation to proceed if the customer's installation target has a serial number that matches one of the vendor-provided serial numbers in the authorization list. Provision is also made for allowing customers to add serial numbers to the list, within constraints predetermined by the software vendor. Also provided is a method for a customer to perform a predetermined number of installations, whereby the software maintains and decrements a counter in an encrypted file on a storage medium, keeping track of how many remaining installations a customer may perform.

Abstract: A method is described for controlling customer installations of software or data by providing to the customer an encrypted list of authorized installation targets, whereby the installation program reads and decrypts the list, and only allows installation to proceed if the customer's installation target has a serial number that matches one of the vendor-provided serial numbers in the authorization list. Provision is also made for allowing customers to add serial numbers to the list, within constraints predetermined by the software vendor. Also provided is a method for a customer to perform a predetermined number of installations, whereby the software maintains and decrements a counter in an encrypted file on a storage medium, keeping track of how many remaining installations a customer may perform.

Abstract: A subsystem of an avionics system is operated in a first mode for receiving software via a port; and in a second mode in accordance with a circuit that includes a terminator coupled to the port. By using the terminator to convey information regarding a desired configuration for operation in the second mode, communication and wiring is avoided between subsystems of the avionics system for conveying such information. In one implementation, operation in the second mode includes performing a collision avoidance function (e.g., providing a TCAS advisory). Configuration information in accordance with the circuit may specify an arrangement of shared antennas between multiple transponders and/or mode changes related to using an antenna for a collision avoidance function in a hijack mode of operation.

Abstract: A method is described for controlling customer installations of software or data by providing to the customer an encrypted list of authorized installation targets, whereby the installation program reads and decrypts the list, and only allows installation to proceed if the customer's installation target has a serial number that matches one of the vendor-provided serial numbers in the authorization list. Provision is also made for allowing customers to add serial numbers to the list, within constraints predetermined by the software vendor. Also provided is a method for a customer to perform a predetermined number of installations, whereby the software maintains and decrements a counter in an encrypted file on a storage medium, keeping track of how many remaining installations a customer may perform.

Abstract: A capacitor is charged and discharged through switch selectable resistors from regulated DC voltage supplies and clamping diodes to provide the bias signal to control the rise and fall times of the RF output pulse of a PIN diode attenuator. An isolation buffer isolates charging and discharging transients from the bias signal. An adjustable AC gain and adjustable DC offset inverting amplifier provides the isolation buffered signal to a high impedance, very low output AC impedance source for driving the bias input of the PIN diode attenuator. The DC offset is provided by an adjustable regulated voltage source coupled to the inverting amplifier.