Abstract: Systems and methods provide techniques for dynamic rate-limiting, such as techniques that utilize one or more of asynchronous rate-limiting, context-aware rate-limiting, and cost-aware rate-limiting. In one example, a method for asynchronous rate-limiting includes the steps of receiving a rate-limiting request for a service application; extracting one or more policy-defining parameters from the rate-limiting request; querying a local cache storage medium associated with the rate-limit decision node to identify one or more local rate-limiting policies associated with the rate-limiting request; determining, based on the one or more policy-defining parameters and the one or more local rate-limiting policies, a rate-limiting decision for the rate-limiting request; and transmitting the rate-limiting decision to the service application in response to the rate-limiting request.

Abstract: A dedicated database system for storing user-generated content created when interacting with an environment defined by a software service. An access control system provides the software service with surrogate keys only and stores an association between surrogate keys and user-generated content in the dedicated database system. Upon receiving a request for user-generated content, the software service returns a surrogate key which can be translated into associated user-generated content by the dedicated database system.

Abstract: Systems and methods provide techniques for dynamic rate-limiting, such as techniques that utilize one or more of asynchronous rate-limiting, context-aware rate-limiting, and cost-aware rate-limiting. In one example, a method for asynchronous rate-limiting includes the steps of receiving a rate-limiting request for a service application; extracting one or more policy-defining parameters from the rate-limiting request; querying a local cache storage medium associated with the rate-limit decision node to identify one or more local rate-limiting policies associated with the rate-limiting request; determining, based on the one or more policy-defining parameters and the one or more local rate-limiting policies, a rate-limiting decision for the rate-limiting request; and transmitting the rate-limiting decision to the service application in response to the rate-limiting request.

Abstract: Embodiments of the invention reduce the probability of success of a DOS attack on a node receiving packets by decreasing the probability of random collisions of packets sent by a malicious user with those sent by honest users. The probability of random collisions may be reduced in one class of embodiments of the invention by supplementing the identification field of the IP header of each transmitted packet with at least one bit from another field of the header. The probability of random collisions may be reduced in another class of embodiments of the invention by ensuring that packets sent from a transmitting IPsec node to a receiving IPsec node are not fragmented.

Abstract: A system facilitates the purchase of an item or service using a wireless device (100). The system may capture an image of a bar code (310) associated with a device (300) from which the item or service is being purchased and transmit the image to facilitate payment for the item or service. The system may alternatively process the image to extract information from the image and transmit the extracted information to facilitate payment for the item or service.