Abstract: An Asynchronous Transfer Mode (ATM) network device having a receiver portion capable of receiving ATM cells on one of a number of virtual circuits (VCs) from an upstream ATM switch, a local memory used to store the ATM cells, a management system to manage the local memory using a number of queues, a system for assembling ATM cells into packets, a system for transmitting the packets to a host memory, and a transmitter portion having a system for indicating the transmitting of packets to the host memory to the upstream ATM switch.

Abstract: A method and apparatus is provided for generating and implementing a "smooth" schedule for forwarding of cells across a switch in a communication network, such as an AIM network. The schedule is obtained by recursively dividing bandwidth requests into nearly equal subrequests, and selectively allocating the subrequests to slots of a frame in a manner that obtains approximately uniform temporal distribution of cell forwarding over the duration of the frame. Implementation of such a schedule can eliminate clustering of cell forwarding across the switch, thereby reducing latency and space requirements for input and output buffering.

Abstract: This invention consists of a method for providing security for distributing management operations among components of a computer network using a network of mutually trusting, mutually authenticating management services to dispatch operations to selected host systems. Mutual authentication and trust are established on every transmission link from a point of submission to a designated management server which invokes a service provider to perform management operations on a selected host.

Abstract: A data transfer device for coupling a processor to a system bus. The data transfer device includes data packers and unpackers for converting between data blocks of a first size and data blocks of a second size, e.g. between bytes or words and longwords. The data transfer device also includes an internal buffer memory system for storing the data being transferred. The processor and system bus are selectively coupled, each one at a time, via a direct data path, to the internal buffer memory system permitting both the processor and the system bus to independently read and write data, each at their normal data transfer rate.

Abstract: A method for displaying discriptive data in which data is presented by vectors with the length of the vector representing one dimension of the data and the angle of the vector representing another dimension of the data. Data having multiple categories is represented by a plurality of component vectors, each extending from the tip of the preceding component vector. The thickness of the vectors represents the variance of the data.

Abstract: An Asynchronous Transfer Mode (ATM) network adapter having a receiver portion, the receiver portion capable of receiving a first plurality of ATM cells and assembling the first plurality of ATM cells into a first plurality of packets, and a transmitter portion, the transmitter receiving a second plurality of packets and segmenting the second plurality of packets into a second plurality of ATM cells, the receiving portion having a local memory for segmentation, while the transmitter portion having no local memory.

Abstract: A data processing system comprising a main memory 10 with a 32-bit longword data bus 11 and an address bus 12, and a link unit 20 using 16-bit shortwords. The link unit has two shortword memories 26 and 28 for descriptor and message shortwords. Descriptor shortwords are exchange individually with the memory 10, residing in the lower halves of longword locations; message shortwords are exchanged with the memory 10 through a concatenation and deconcatenation unit 40 so that they are stored in pairs in longword locations. Unit 20 passes descriptor addresses (with top bit 1) from a register 25 and message addresses (with top bit 0) from a register 27 to the main memory through address processing means 36, which comprises a multiplexer 43 with its two data inputs fed with two versions of the address with a 1-bit shift between them. The top address bit controls the multiplexer, so that the main memory address steps by 1 for every step of a descriptor address or every second step of a message word address.

Abstract: A network adapter for interfacing between a communication network and a host computer operating as a network device, and a method of operation of these components. The adapter is initially conditioned to transmit at a lower of two possible speeds, such as 10 Mbps instead of 100 Mbps, and then senses at which speed the network is operating, before matching to this sensed speed, either the higher speed or the lower speed. If the sensed speed is the lower speed, the adapter transmits a burst of high-speed signals and senses again for high-speed operation. If the network has not switched to high-speed operation, the adapter is conditioned for low-speed operation. After the adapter is conditioned for low-speed or high-speed operation, the network speed is continually sensed and, if the network is not operating at the selected speed for some preselected period of time, the adapter is returned to its initial low-speed state to begin network speed sensing over again.

Abstract: A method and corresponding apparatus for authenticating a client for a server when the client and server have different security mechanisms. An intermediary system known as an authentication gateway provides for authentication of the client using the client security mechanism, and impersonation of the client in a call to a server that the client wishes to access. The client logs in to the authentication gateway and provides a user name and password. Then the authentication gateway obtains and saves security credentials for the client, returning an access key to the client. When the client wishes to call the server, the client calls the authentication gateway acting as a proxy server, and passes the access key, which is then used to retrieve the security credentials and to impersonate the client in a call to the server. Any output arguments resulting from the call to the server are returned to the client through the authentication gateway.

Abstract: A technique for generating, distributing and maintaining a list of operational nodes in a network using a nonbroadcast communication medium, wherein the nodes first collectively agree on the identity of a designated node. Once the designated node is agreed on, the other nodes periodically send Hello messages to it and the designated nodes compiles a list of operational nodes based in part on the Hello messages it receives, and periodically sends a Hello message to each node on the list. The Hello message from the designated node includes a list of addresses of active neighbor nodes, so that every node periodically receives a list of operational neighbor nodes. The number of messages needed to implement this scheme is proportional to the number of nodes, rather than the square of the number of nodes as in a conventional approach in which each node advised every other node of its presence.

Abstract: A method of transferring data to insure data authenticity is provided comprising the steps of providing a first computer system, the first computer system having a mass storage device, a central processing unit having a encoding/decoding device, and a communication device, providing a second computer system, the second computer system having a mass storage device, a central processing unit having a encoding/decoding device, and a communication device, linking the first computer system to the second computer system via a network communications link, providing a database on the mass storage device of the first computer system, the database containing a plurality of records, selecting a subset of the plurality of records, encoding said subset into a signet, transferring the signet to the second computer system over the network communications link, transferring the subset to the second computer system over the network communications link, transferring the subset to the second computer system over the network comm

Abstract: In an asynchronous transfer mode (ATM) endnode a method is provided by which ATM cells can experience a small delay from the ATM layer to the PHY layer to transmission on the ATM network.

Abstract: A method providing automating detection of configuration between an adapter device and a DRAM device. Such a method a determines, in the adapter memory, the DRAM configuration, making it easier to change DRAM configuration in an existing board without the need to modify configuration pins in the existing board. A method for determining a configuration type in an Asynchronous Transfer Mode (ATM) communications network comprising the steps of providing an ATM adapter, the ATM adapter having an ATM adapter memory, providing a DRAM device, the DRAM device having a DRAM configuration, providing a link to connect the ATM adapter and the DRAM device, assuming, in the ATM adapter memory, a first DRAM configuration, verifying the step of assuming, and repeating the steps of assuming and verifying until the first DRAM configuration is determined.

Abstract: The invention concerns the upper layers of the OSI 7-layer system interconnection model, and specifically the upper 3 layers (session, presentation, and application). The three layer state tables of the standard system are merged (amalgamated) into a single state table. Merged component state tables 28' are looked up by the message PDU (protocol data unit) in register 11' and the merged state in register 26' and the entries (predicate, actions, and next state combinations) are processed by an entry logic unit 31', a predicate logic unit 32', and a variable list 33'. In merging the state tables, the data phase services of the session and presentation layers have to be merged. The presentation layer service P-ALTER-CONTEXT requires 4 states for each of the supporting session states. The number of states of the merged tables concerned with this is divided by 4 by using a new variable, p-state, which represents the 4 session layer states associated with P-ALTER-CONTEXT.

Abstract: A system for delineating partially- or fully-bounded areal regions of a map utilizes deformable templates, which it dynamically expands and contorts to conform to the boundaries of the regions. The system segments the map into a number of cells, with each cell relating, for example, to a pixel. The system then defines an "energy" field for the floor plan by assigning cells corresponding to boundary edges predetermined minimum energy values, cells corresponding to boundary interiors predetermined maximum energy values, and each non-boundary cell an energy value defined by the distance of the cell from the closest boundary edge cell. The system then iteratively manipulates a template over a selected region of the floor plan in an attempt to minimize the "potential" of the template, which is defined by a potential function that includes a "total energy score" and various size and test terms that encourage desired template deformations.

Abstract: An implementation efficient interrupt select mechanism which allocates interrupt flags between N interrupt requestors, e.g. communication channels. A multi-channel controller provides the select mechanism with control signals and asserts an interrupt request when a channel, being visited by a scanner, which may be incorporated into the controller, is asserting an interrupt request. If the interrupt flag is available, the number of the channel asserting the request is locked into a latch. The latch remains locked until the interrupt request is cleared, a control signal is received from the controller and the channel being visited by the scanner equals the channel number stored in the latch. The scanner increments from channel to channel regardless of the assertion of the interrupt flag or the locking of the latch. In this manner, a single scanner may be used with any number or interrupt select mechanisms.

Abstract: The distributed computation of max-min fair rates in general require lookups for all connections. This present method includes a distributed process for computing max-min fair rates in response to a rate allocation request by any connection. The method computes the optimal rate by performing a single lookup of the state for a particular connection. The discrepancies due to omitting the lookup for other connections are corrected when those connections request a rate allocation.

Abstract: An arbiter of an I/O controller implements an arbitration process for controlling bi-directional data flow between a local area network and a main memory connected to a system bus having variable latency. A receive state machine of the controller manages inbound data bursts from the network by temporarily storing the data in a receive buffer before transfer to the main memory. Outbound data bursts from the main memory are managed by a transmit state machine of the controller, and are temporarily stored in a transmit buffer prior to transmission onto the network. The arbitration process assigns each of the receive and transmit state machines priority for accessing the system bus depending upon certain status conditions of the controller.

Abstract: A method and apparatus for adaptive interrupt servicing is disclosed. The number of interrupts occurring within a predetermined time period is counted and stored as a value in an interrupt counter. At the end of each interrupt service, the interrupt counter value is compared to a predefined threshold value. If the value in the interrupt counter equals or exceeds the threshold value, further interrupt servicing is disabled.

Abstract: A distributed computer system employs certificate based alias detection to ensure a policy of separation of duties. Biometric information is collected during computer user account creation that is converted to canonical form and digitized. This digitized canonical form, along with account data and authentication data, is included in the user's account information. Authorization to execute any task is validated at the time a request is made by comparison of the digitized canonical forms of biometric data of the user completing the request with those of the user initiating the request.