Abstract: Methods and apparatus for scheduling cell transmission over a network link by a switch. The switch includes a plurality of queues associated with each link. Lists of queues are maintained for each link. In one embodiment, each link is associated with more than one type of list (with the list type corresponding to a scheduling category) and more than one prioritized list of each type (with the priority of the list corresponding to a quality of service). The scheduling lists are accessed to permit cell transmission from a queue contained therein in a predetermined sequence as a function of scheduling category, priority within a particular scheduling category and whether the bandwidth requirement for the particular scheduling category has been met. With this arrangement, maximum permissible delay requirements for each scheduling category are met.

Abstract: An apparatus and a method are disclosed for unencumbering valuable switching resources in a network switch involved in a multipoint-to-multipoint switching scenario. The network switch includes an input processing port that is connected to a plurality of input links, and an output processing port that is connected to a plurality of output links. A data cell received on an input link is processed by the input processing port by appending a link number, a port number, and a connection identification code associated with the input processing port to the data cell. The data cell is then transferred to the output processing port where it is processed by comparing the appended link number, port number, and connection identification code with those associated with the output processing port. The data cell is then stored in a data buffering queue in the output processing port according to a matching scheme.

Abstract: A system (10) is provided for mapping a data cell (32) in a communication switch. The system (10) includes a virtual translation table (40) having at least one virtual path translation table queue entry (92) and at least one virtual channel translation table queue entry (90). A to-switch port processor (12), which can access the virtual translation table (40), has at least one link (16-30) which receives the data cell (32). The to-switch port processor (12) maps the received data cell (32) to a queue descriptor using the virtual translation table (40).

Abstract: A system for managing resources such as buffers and bandwidth which are allocated to competing entities through two or more levels in a telecommunications network is disclosed. The system provides a tool to allocate resources for use by individual entities. Each entity may be assigned a Minimum.sub.-- Guaranteed variable and a Maximum.sub.-- Allowed variable. When an entity requests resources the system determines if the entity is using its respective minimum guaranteed resource allocation which is specified by the Minimum.sub.-- Guaranteed variable. If the entity is not using its respective minimum guaranteed resource allocation, the system allocates a resource unit to the requesting entity. The system also allows a requesting entity to use additional resource units above the resource allocation specified by the Minimum.sub.-- Guaranteed variable, provided such resource units are available.

Abstract: An ATM-Ethernet portal/concentrator permits a transparent interconnection between Ethernet segments over an ATM network to provide remote connectivity for Ethernet segments. The portal includes an Ethernet controller and an ATM cell processor, both of which receive and transmit data to and from a dual port shared memory under control of a direct memory access controller. A control microprocessor monitors and controls the shifting of data through the dual port memory. In this scheme, original data is written and read directly into and out of the dual port memory to thereby eliminate any requirement for copying of data, to thereby significantly increase the data throughput capability of the portal. In the concentrator embodiment, a plurality of Ethernet controllers, each of which is connected to its own associated Ethernet segment, is multiplexed through the concentrator to an ATM network to thereby provide remote connectivity for each of the Ethernet segments.

Abstract: An ATM-Ethernet portal/concentrator permits a transparent interconnection between Ethernet segments over an ATM network to provide remote connectivity for Ethernet segments. The portal includes an Ethernet controller and an ATM cell processor, both of which receive and transmit data to and from a dual port shared memory under control of a direct memory access controller. A control microprocessor monitors and controls the shifting of data through the dual port memory. In this scheme, original data is written and read directly into and out of the dual port memory to thereby eliminate any requirement for copying of data, to thereby significantly increase the data throughput capability of the portal. In the concentrator embodiment, a plurality of Ethernet controllers, each of which is connected to its own associated Ethernet segment, is multiplexed through the concentrator to an ATM network to thereby provide remote connectivity for each of the Ethernet segments.