Abstract: In carrying out a task that consumes data from a one-time pad, task inputs comprising at least first data and second data from the pad, are combined together to form an output from which the data used from the pad cannot be recovered without knowledge of at least one of the first and second data. The task concerned can be, for example, the encrypting of a message or the creating of an attribute verifier.

Abstract: A device is arranged to carry out security-related tasks using one-time pad data. The device has a memory for holding multiple one-time pads, each pad having a different security rating and being intended for use by the device in executing a task to that security rating. Provisioning of the pads with one-time pad data involves carrying out a process for obtaining new secret random data. This process has a security rating with the value of this rating varying according to the nature and parameters of the process concerned. The security rating of the process used to obtain the new secret random data is matched to that of the pad to be provisioned with one-time data, or the other way around, such that the security rating of the process is as least as good as that of the pad to be provisioned.

Abstract: Secret random data is distributed to a plurality of devices to provision them with new one-time pad data for use in interacting with apparatus holding the same one-time pad data. This distribution is effected by provisioning a first device with a block of secret random data that is, or will become, available to the apparatus. Part of the secret random data is then distributed from the first device to one or more other devices in a hierarchical distribution pattern headed by the first device. Each device, other than those at the bottom of the distribution hierarchy, retains part of the secret random data it receives and passes on the remainder. Each device uses that part of the secret random data it has retained to provide the device with new one-time pad data. A method is also provided for tracking service usage based on the distributed one-time pad data.

Abstract: A device stores one-time pad data for use in carrying out various tasks. In order to preserve the ability to carry out important tasks that require the use of one-time data, use of the one-time pad data held by the device is controlled such that an amount of this one-time pad data is only usable by a predetermined set of important tasks comprising at least a replenishment task for replenishing the device with one-time pad data.

Abstract: A method of analysing a network having a plurality of computing and infrastructure elements, some of which run agents that monitor one or more network phenomenon, the method comprising the steps of: disabling a selected infrastructure element on which it is not possible to run a monitoring agent; acquiring data from an element adjacent a disabled element; and generating, from the acquired data, a signature representative of the selected element being inoperative.

Abstract: Apparatus for producing an electronic model of a communications network or system having at least one host and a plurality of nodes connected thereto, directly or otherwise, the apparatus comprising means for obtaining data relating to at least some of the nodes and/or the host and means for creating an electronic model of the system or network using the data. The apparatus comprises a trusted computer host for use in analysing the network. The trusted computer host comprises means for detecting nodes on the network. As nodes are detected, sampling probes are inserted at each such node wherever possible. The probes take measurements at the respective nodes and return the resultant data to the trusted computer host. For a case where it is not possible to insert a probe at a detected node, the trusted computer host comprises means for performing traffic analysis and obtaining a profile of behavior between that node and the network host.

Abstract: A method of configuring a supercomputer having a plurality of computing elements, each having an irreducible core computing capability to store and retrieve data, includes the steps of: defining an operating time interval; establishing an desired probability of successful operation over the operating time interval; having regard to the total number of computing elements, configuring each computing element so that, over the operating time interval, the probability of successful operation of the irreducible core capability of each computing elements is greater than, or equal to, the desired probability of successful operation over the operating time interval.

Abstract: A method of operating a supercomputer having a plurality of computing elements each connected to a fast communications link is disclosed, the method comprising the steps of: scheduling specified elements to perform computing tasks in specified cycles of a computing operation; in the event of failure of a fast communications link in a given cycle, transferring state from a disabled element no longer able to communicate as a result of the failure to an idle element not scheduled to perform a task in the given cycle; operating the idle element to perform any uncompleted tasks scheduled for the disabled element remaining in the cycle.

Abstract: A communication system includes a data base storing voice applications corresponding to programs executable by user equipment and user profiles. The voice applications are arranged to provide assistance in relation to the programs. A communication handler causes execution of a voice application from the data base responsive to user identification data.

Abstract: Methods are described for securing access to an electronic annotation provided on an object. The methods include the steps of providing the object with a plurality of memory tags, providing an electronic annotation on at least one of the memory tags, and defining a sequence in which the memory tags must be accessed in order to access the annotation. A corresponding object is also described.

Abstract: Security keys for the provision of a secure service such as content provision are generated in an ancestral hierarchy, so that invalidation of a key in the hierarchy results in a need to reconfigure all other keys in the hierarchy to the extent they share common ancestry. When a user subscription to the service lapses, a decision on invalidation of their key is based in a determination of whether it's more costly to the subscriber to invalidate the key, or continue providing an unpaid-for service. Keys can be allocated to users from domains of the hierarchy on the basis of their economic value to the provider, with higher value users being allocated keys from domains which share fewer common ancestors with other users of other domains than those users share with each other, to minimise inconvenience to high value users of key reconfiguration.

Abstract: An information technology network comprises a plurality of printers and at least one computing entity which serves as a print manager. The print manager is adapted to process print jobs by distributing the ripping process between two or more different printers, and then returning disparately ripped data to a single printer for physical marking of documents with indicia in accordance with the ripped data.

Abstract: Security keys for the provision of a secure service such as content provision are generated in an ancestral hierarchy, so that invalidation of a key in the hierarchy results in a need to reconfigure all other keys in the hierarchy to the extent they share common ancestry. When a user subscription to the service lapses, a decision on invalidation of their key is based in a determination of whether it's more costly to the subscriber to invalidate the key, or continue providing an unpaid-for service. Keys can be allocated to users from domains of the hierarchy on the basis of their economic value to the provider, with higher value users being allocated keys from domains which share fewer common ancestors with other users of other domains than those users share with each other, to minimize inconvenience to high value users of key reconfiguration.

Abstract: A method of operating a supercomputer having N computing elements each connected to a fast communications link is disclosed, the method comprising the steps of: operating the supercomputer to perform a computing operation; upon failure of a fast communications link transferring state from a computing element which, as a result of the fast communications link failure, is no longer able to communicate, to a spare computing element not previously engaged in the computing operation, and continuing the computing operation with the spare computing element, wherein the number of redundant elements M is chosen to satisfy the expression BM[N, (1?PT)]>S where S is a desired probability of successful completion of the computing operation within a time T and P is the probability of successful operation per unit time of a fast communications link.

Abstract: A device is arranged to carry out security-related tasks using one-time pad data. The device has a memory for holding multiple one-time pads, each pad having a different security rating and being intended for use by the device in executing a task to that security rating. Provisioning of the pads with one-time pad data involves carrying out a process for obtaining new secret random data. This process has a security rating with the value of this rating varying according to the nature and parameters of the process concerned. The security rating of the process used to obtain the new secret random data is matched to that of the pad to be provisioned with one-time data, or the other way around, such that the security rating of the process is as least as good as that of the pad to be provisioned.

Abstract: A computer network comprises plural computer systems connected to plural printers. Each computer system comprises at least one application program for generating print data for one or more of the printers. One of the computer systems is partially employed as a stock control computer. An application program stored on the stock control computer runs a model of the overall system, including maintaining an up-to-date schedule of all print jobs on the system, and maintains a log of all media resources (i.e., paper) available to each printer. The application program ensures that the printers have suitable media resources and/or that print jobs are allocated to printers where appropriate media resources are available, if possible.

Abstract: A device stores one-time pad data for use in carrying out various tasks. In order to preserve the ability to carry out important tasks that require the use of one-time data, use of the one-time pad data held by the device is controlled such that an amount of this one-time pad data is only usable by a predetermined set of important tasks comprising at least a replenishment task for replenishing the device with one-time pad data.

Abstract: A multi-stage or process operation, such as the printing of a document from a data file in the form of a word processing document may be performed either by passing the document directly along a relatively fast network link to a printer 300, or by passing the document along a relatively slow link to a printer 200, where the document is ripped, and then passing the ripped data along a further relatively fast link to printer 300. To determine the optimum course of action in view of a policy demanding speed of printing the probable speed of each course of action is determined, and the course of action most likely to yield a result in conformity with the policy is selected.

Abstract: Secret random data is distributed to a plurality of devices to provision them with new one-time pad data for use in interacting with apparatus holding the same one-time pad data. This distribution is effected by provisioning a first device with a block of secret random data that is, or will become, available to the apparatus. Part of the secret random data is then distributed from the first device to one or more other devices in a hierarchical distribution pattern headed by the first device. Each device, other than those at the bottom of the distribution hierarchy, retains part of the secret random data it receives and passes on the remainder. Each device uses that part of the secret random data it has retained to provide the device with new one-time pad data. A method is also provided for tracking service usage based on the. distributed one-time pad data.

Abstract: A system is disclosed in which a plurality of devices are arranged to use one-time pad data to interact with apparatus holding the same one-time pad data. Each of the devices and the apparatus has its own one-time pad and the pads are all provisioned with the same new one-time pad data. Upon any one of the devices wishing to effect an interaction with the apparatus using one-time pad data, an alignment operation is carried out between a set of entities comprising at least the apparatus and the device wishing to carry out the interaction. The alignment operation serves to reduce the level of the one-time pad of at least the device wishing to carry out the interaction, to the level of the lowest one-time pad of the set of entities involved in the alignment operation.