Abstract: A sampling switch circuit, comprising an input node, connected to receive an input voltage signal, a sampling transistor comprising a gate terminal, a source terminal and a drain terminal, the source terminal connected to the input node, a hold-control node connected to receive a hold-control voltage signal, an output node connected to the drain terminal of the sampling transistor, a buffer circuit having a buffer input connected to the input node and a buffer output connected to a track-control node, the buffer circuit configured to provide a track-control voltage signal at the track-control node dependent on the input voltage signal and switching circuitry configured to connect the gate terminal of the sampling transistor to the track-control node or to the hold-control node in dependence upon a clock signal.

Abstract: A sample and hold circuit includes: an input node to which an input voltage signal is configured to be supplied; a first reference voltage node to which a first reference voltage potential is configured to be supplied; a sampling capacitor circuit; a sampling switch transistor circuit connected between the input node and the sampling capacitor circuit; a first common mode switch transistor circuit connected between the sampling capacitor circuit and the first reference voltage node; a signal bootstrap circuit configured to generate a first control voltage based on a clock signal, the first control voltage varying according to a level of the input voltage signal, and configured to control the sampling switch transistor circuit based on the first control voltage; and a static bootstrap circuit configured to generate a second control voltage based on the clock signal, the second control voltage being programmable, and configured to control the first common mode switch transistor circuit based on the second contr

Abstract: A sampling switch circuit, including an input node, which receives an input voltage signal to be sampled, a sampling transistor having gate, source and drain terminals, the source terminal connected to the input node, a capacitor, a current source configured to cause a defined current to flow therethrough and switching circuitry configured to alternate between a precharge configuration and an output configuration depending upon a clock signal. In the precharge configuration, the switching circuitry connects the capacitor into a current path between said current source and a first voltage reference node to form a potential difference across the capacitor which is dependent on the defined current. In the output configuration, the switching circuitry connects the capacitor between a second voltage reference node and the gate terminal of the sampling transistor so that a voltage level applied at the gate terminal of the sampling transistor is dependent on the defined current.

Abstract: A sampling switch circuit, comprising an input node, connected to receive an input voltage signal, a sampling transistor comprising a gate terminal, a source terminal and a drain terminal, the source terminal connected to the input node, a hold-control node connected to receive a hold-control voltage signal, an output node connected to the drain terminal of the sampling transistor, a buffer circuit having a buffer input connected to the input node and a buffer output connected to a track-control node, the buffer circuit configured to provide a track-control voltage signal at the track-control node dependent on the input voltage signal and switching circuitry configured to connect the gate terminal of the sampling transistor to the track-control node or to the hold-control node in dependence upon a clock signal.

Abstract: A sampling switch circuit, including an input node, which receives an input voltage signal to be sampled, a sampling transistor having gate, source and drain terminals, the source terminal connected to the input node, a capacitor, a current source configured to cause a defined current to flow therethrough and switching circuitry configured to alternate between a precharge configuration and an output configuration depending upon a clock signal. In the precharge configuration, the switching circuitry connects the capacitor into a current path between said current source and a first voltage reference node to form a potential difference across the capacitor which is dependent on the defined current. In the output configuration, the switching circuitry connects the capacitor between a second voltage reference node and the gate terminal of the sampling transistor so that a voltage level applied at the gate terminal of the sampling transistor is dependent on the defined current.

Abstract: Differential attenuation circuitry, including: first and second input nodes; first and second output nodes; and an impedance network connected between the first and second input nodes and the first and second output nodes to provide a differential output voltage signal between the first and second output nodes which is attenuated compared to a differential input voltage signal applied between the first and second input nodes, wherein the impedance network includes: a common-mode node; a first impedance network connected between the first input node, the common-mode node and the first output node; and a second impedance network connected between the second input node, the common-mode node and the second output node, and wherein the differential attenuation circuitry further includes: an input-to-input path comprising one or more impedances and one or more switches connected between the first and second input nodes to provide a current path independent of the common-mode node.

Abstract: Current-generation circuitry, comprising: a plurality of candidate current sources operable to generate respective candidate currents; an output current source operable to generate an output current; comparator circuitry; and control circuitry operable to control the current sources and the comparator circuitry to: in an adjustment step, generate an adjustment current by selecting one of the candidate currents or by summing together a plurality of the candidate currents, and calibrate at least a plurality of the candidate current sources; and in a calibration step, following the adjustment step, generate a reference current by selecting one of the candidate currents generated by the candidate current sources calibrated in the adjustment step or by summing together a plurality of the candidate currents generated by those candidate current sources, and calibrate the output current source by comparing its output current to that reference current and adjusting a control signal applied to that output current sourc

Abstract: Current-generation circuitry, comprising: a plurality of candidate current sources operable to generate respective candidate currents; an output current source operable to generate an output current; comparator circuitry; and control circuitry operable to control the current sources and the comparator circuitry to: in an adjustment step, generate an adjustment current by selecting one of the candidate currents or by summing together a plurality of the candidate currents, and calibrate at least a plurality of the candidate current sources; and in a calibration step, following the adjustment step, generate a reference current by selecting one of the candidate currents generated by the candidate current sources calibrated in the adjustment step or by summing together a plurality of the candidate currents generated by those candidate current sources, and calibrate the output current source by comparing its output current to that reference current and adjusting a control signal applied to that output current sourc

Abstract: Computer systems and methods in various embodiments are configured to test the security of a server computer by simulating a wide range of attacks from one or more bot-nets. In an embodiment, a computer system includes a memory; a processor coupled to the memory; a plurality of network cards coupled to the processor and the memory, the computer system being located in a home geographic region; wherein each of the plurality of network cards is configured to send one or more requests to a remote server computer through one of a plurality of geographic regions, that is different than the home geographic region; wherein, for each of the plurality of network cards, the processor is configured to store in the memory one of a plurality of geo-mappings, wherein the geo-mapping indicates the certain geographic region the network card is configured to send the one or more requests to the remote server computer through.

Abstract: Computer systems and methods in various embodiments are configured to test the security of a server computer by simulating a wide range of attacks from one or more bot-nets. In an embodiment, a computer system comprising a memory; a processor in a home geographic region coupled to the memory; a plurality of network cards in the home geographic region, coupled to the processor and the memory; wherein each network card in the plurality of network cards is configured to send one or more requests to a remote server computer through a geographic region, of a plurality of geographic regions, that is different than the home geographic region; wherein, for each network card of the plurality of network cards, the processor is configured to store in the memory a geo-mapping, of a plurality of geo-mappings, wherein the geo-mapping indicates the certain geographic region the network card is configured to send the one or more requests to the remote server computer through.

Abstract: Computer systems and methods in various embodiments are configured to test the security of a server computer by simulating a wide range of attacks from one or more bot-nets. In an embodiment, a computer system including a memory; a processor in a home geographic region coupled to the memory; a plurality of network cards in the home geographic region, coupled to the processor and the memory; wherein each network card in the plurality of network cards is configured to send one or more requests to a remote server computer through a geographic region, of a plurality of geographic regions, that is different than the home geographic region; wherein, for each network card of the plurality of network cards, the processor is configured to store a geo-mapping, which indicates the certain geographic region the network card is configured to send the one or more requests to the remote server computer through.

Abstract: Various technologies pertaining to instant messaging are described herein. A persistent instant messaging group is created, wherein the persistent instant messaging group comprises a plurality of members and persists over a plurality of instant messaging sessions. Instances of an instant messaging application are installed on mobile telephones, and the instant messaging application is used to transmit instant messages between members of the persistent instant messaging group. Messages directed towards offline members of the persistent instant messaging group are transmitted to such members when they come online.

Abstract: Various technologies pertaining to instant messaging are described herein. A persistent instant messaging group is created, wherein the persistent instant messaging group comprises a plurality of members and persists over a plurality of instant messaging sessions. Instances of an instant messaging application are installed on mobile telephones, and the instant messaging application is used to transmit instant messages between members of the persistent instant messaging group. Messages directed towards offline members of the persistent instant messaging group are transmitted to such members when they come online.

Abstract: Functionality is described for collecting data from a presence-based system, such as an instant messaging system. The functionality can extract information from the collected data based on one or more rules. For instance, the functionality can identify presence data and/or message data that includes predetermined key words. The functionality can formulate result information based on the extracted information for presentation to a recipient.

Abstract: Various technologies pertaining to instant messaging are described herein. A persistent instant messaging group is created, wherein the persistent instant messaging group comprises a plurality of members and persists over a plurality of instant messaging sessions. Instances of an instant messaging application are installed on mobile telephones, and the instant messaging application is used to transmit instant messages between members of the persistent instant messaging group. Messages directed towards offline members of the persistent instant messaging group are transmitted to such members when they come online.

Abstract: A system described herein includes a receiver component that receives a request to create a persistent messaging group for an instant messaging application, wherein the request includes an indication of one or more entities that are desired to be members of the persistent messaging group. The system further includes a group creator component that creates the persistent messaging group based at least in part upon the received group creation request, wherein the persistent messaging group is persisted over multiple instant messaging sessions.

Abstract: Functionality is described for collecting data from a presence-based system, such as an instant messaging system. The functionality can extract information from the collected data based on one or more rules. For instance, the functionality can identify presence data and/or message data that includes predetermined key words. The functionality can formulate result information based on the extracted information for presentation to a recipient.

Abstract: A system described herein includes a receiver component that receives a request to create a persistent messaging group for an instant messaging application, wherein the request includes an indication of one or more entities that are desired to be members of the persistent messaging group. The system further includes a group creator component that creates the persistent messaging group based at least in part upon the received group creation request, wherein the persistent messaging group is persisted over multiple instant messaging sessions.

Abstract: Functionality is described for collecting data from a presence-based system, such as an instant messaging system. The functionality can extract information from the collected data based on one or more rules. For instance, the functionality can identify presence data and/or message data that includes predetermined key words. The functionality can formulate result information based on the extracted information for presentation to a recipient. Based on these operations, the collected data supports a data-mining operation, as well as the traditional role of facilitating communication among the participants of the presence-based system. The result information can correspond to a report that presents aggregated findings, optionally organized into one or more demographic categories, or the result information can correspond to an advertisement, etc.

Abstract: A system described herein includes a receiver component that receives a request to create a persistent messaging group for an instant messaging application, wherein the request includes an indication of one or more entities that are desired to be members of the persistent messaging group. The system further includes a group creator component that creates the persistent messaging group based at least in part upon the received group creation request, wherein the persistent messaging group is persisted over multiple instant messaging sessions.