A system for controlling use and distribution of digital works, in which the owner
of a digital work (101) attaches usage rights (102) to that work. Usage rights are granted by the
"owner" of a digital work to "buyers" of the digital work. The usage rights define how a
digital work may be used and further distributed by the buyer. Each right has associated with it
certain optional specifications which outline the conditions and fees upon which the right may
be exercised. Digital works are stored in a repository. A repository will process each request
(103,104) to access a digital work by examining the corresponding usage rights (105). Digital
work playback devices, coupled to the repository containing the work, are used to play, display
or print the work. Access to digital works for the purposes of transporting between
repositories (e.g. copying, borrowing or transfer) is carried out using a digital work transport
protocol. Access to digital works for the purposes of replay by a digital work playback
device(e.g. printing, displaying or executing) is carried out using a digital work playback
protocol. Access is denied (106) or granted (107) depending whether the requesting repository
has the required usage rights.

System for controlling the distribution and use of digital works

This paper analyzes the causes of packet loss in a 38-node urban multi-hop 802.11b network. The patterns and causes of loss are important in the design of routing and error-correction protocols, as well as in network planning.The paper makes the following observations. The distribution of inter-node loss rates is relatively uniform over the whole range of loss rates; there is no clear threshold separating "in range" and "out of range." Most links have relatively stable loss rates from one second to the next, though a small minority have very bursty losses at that time scale. Signal-to-noise ratio and distance have little predictive value for loss rate. The large number of links with intermediate loss rates is probably due to multi-path fading rather than attenuation or interference.The phenomena discussed here are all well-known. The contributions of this paper are an understanding of their relative importance, of how they interact, and of the implications for MAC and routing protocol design.

/pdf/link-level-measurements-from-an-802-11b-mesh-network-2y0lbcciyz.pdf

Link-level measurements from an 802.11b mesh network

A system for controlling the distribution and use of digital works using digital tickets. In the present invention, a “digital ticket” is used to entitle the ticket holder to exercise some usage right with respect to a digital work. Usage rights are used to define how a digital work may be used or distributed. Each usage right may specify a digital ticket which must be present before the right may be exercised. Digital works are stored in repositories which enforce a digital works usage rights. Each repository has a “generic ticket agent” which punches tickets. In some instances only the generic ticket agent is necessary. In other instances, punching by a “special ticket agent” residing on another repository may be needed.

System for controlling the distribution and use of digital works using digital tickets

With the success of wireless technologies in consumer electronics, standard wireless technologies are envisioned for the deployment in industrial environments as well. Industrial applications involving mobile subsystems or just the desire to save cabling make wireless technologies attractive. Nevertheless, these applications often have stringent requirements on reliability and timing. In wired environments, timing and reliability are well catered for by fieldbus systems (which are a mature technology designed to enable communication between digital controllers and the sensors and actuators interfacing to a physical process). When wireless links are included, reliability and timing requirements are significantly more difficult to meet, due to the adverse properties of the radio channels. In this paper, we thus discuss some key issues coming up in wireless fieldbus and wireless industrial communication systems: 1) fundamental problems like achieving timely and reliable transmission despite channel errors; 2) the usage of existing wireless technologies for this specific field of applications; and 3) the creation of hybrid systems in which wireless stations are incorporated into existing wired systems.

/pdf/wireless-technology-in-industrial-networks-3inkv4crnj.pdf

Wireless Technology in Industrial Networks

A secure data parser is provided that may be integrated into any suitable system for securely storing and communicating data. The secure data parser parses data and then splits the data into multiple portions that are stored or communicated distinctly. Encryption of the original data, the portions of data, or both may be employed for additional security. The secure data parser may be used to protect data in motion by splitting original data into portions of data, that may be communicated using multiple communications paths.

Secure data parser method and system

A central security control system (security system) interfaces between a plurality of requesters and a plurality of destinations such that it receives from the requesters requests for access to the destinations and communicates to the destinations a level of access that should be granted to a requester by that destination on a per request basis. In a preferred embodiment the security system also a) authenticates the requester to a predetermined level from which the level of access that is to be granted is derived and b) causes a direct connection to be established between the requester and the destination.

Centralized security control system

An access control system is implemented with a maximum-likelihood "soft" decision process that determines whether a user's actions are most like those of a valid user or most like those of a hacker. Data obtained from transactions involving both valid users and hackers is clustered in a multidimensional attribute space, with each of the clusters representing an attribute profile of similar user behaviors. The similarity between the attributes of an access attempt and the attribute profiles represented by the clusters is evaluated, to identify profiles of valid and fraudulent users that most closely resemble the attributes of the access attempt. An access decision can then be made simply based upon which type of user (valid or fraudulent) the access attempt most closely resembles. Alternatively, the access decision can be made by comparing probabilities of eligibility for access, based upon the relative closeness of the resemblances between the profiles for valid and fraudulent users and the profile of the user attempting to gain access, and a function which relates the probability of eligibility to other factors, such as the confidence of the decision, the value of the resource, and so on. In this way, a particular access request is characterized as most likely valid or most likely fraudulent. The history of previous access attempts by particular users may be stored and used subsequently in the access decision process.

System and method for granting access to a resource

An authenticator card includes a liquid crystal display arranged to exhibit a dynamically changeable bar code pattern that represents an account number and, optionally, a PIN and/or expiration date. The card includes circuitry for periodically changing the bar code in accordance with a predetermined algorithm. When the card is presented by a user to a merchant to authenticate the identity of the user in connection with a business transaction, the bar code is scanned by a conventional bar code reader. The code is convened to electronic form and transmitted to a verification processor to be authenticated. During authentication, a corresponding algorithm is used to validate information from the received signal, enabling a database query to determine validity of the card. Advantageously, the card can be mass produced at low cost, and a readily available bar code scanner provides a simple interface when the card is presented for authentication.

Authenticator card and system

A wireless simulcast system, such as an OFDM network, includes the ability to determine the location of a mobile user. Location-based services can be provided to the mobile user.

Simulcasting OFDM system having mobile station location identification

A security system controlling access to a resource is arranged to operate such that when an attempt to access a resource using a password or PIN fails, the time interval "t" that must elapse before a subsequent attempt at access can be successful, is incremented. By making the increments increasingly large (illustratively, an exponential function of the number "n" of unsuccessful attempts), repeated access attempts by hackers or other unauthorized users is discouraged, because they simply cannot wait the time needed to make a large number of trial and error attempts. On the other hand, valid users, while experiencing a delay prior to access, are nevertheless able to gain access, rather than being completely "lockedout". This approach is a better compromise between access control and denial.

Bruce E. McNair

Papers

Centralized security control system

System and method for granting access to a resource

Authenticator card and system

Simulcasting OFDM system having mobile station location identification

Security system providing lockout for invalid access attempts