Abstract: The present invention discloses a memory sharing mechanism based on priority elevation. In accordance with the present invention, there is provided an apparatus and method for transporting packets of data in a communication device, wherein each packet is assigned one of several priorities and received based on memory state information. The method comprises the steps of storing the received packets in a memory and modifying the assigned priority of any of the packets causing congestion within the memory.

Abstract: An apparatus for classifying a data packet includes an interface for receiving the data packet; a classification controller for parsing the data packet to identify a plurality of data items required for classifying the data packet; memory for storing a set of range identifiers for each data item in the data packet corresponding to a rule range defined in the rule sets; and a controller for performing a preliminary test of at least one of the data items to determine whether any of the data item's values match known frequently-occurring values for that data item.

Abstract: Discloses a switching arrangement for packets of data, with several input ports and several output ports and which is determined for the transportation of incoming packets to one or more designated of the output ports and from there to a subsequent device. More particularly it relates to a switching arrangement and method wherein for each input port a set of output buffers is arranged, each set comprising an output buffer for each output port.

Abstract: An apparatus for classifying a data packet includes an interface for receiving the data packet; a classification controller for parsing the data packet to identify a plurality of data items required for classifying the data packet; memory for storing a set of range identifiers for each data item in the data packet corresponding to a rule range defined in the rule sets; and a controller for performing a preliminary test of at least one of the data items to determine whether any of the data item's values match known frequently-occurring values for that data item.

Abstract: Methods and apparatus are provided for classifying data packets in a data processing device. In one aspect, packets are classified according to a plurality of sets of processing rules. Each rule defines a plurality of rule ranges, each rule range indicating a range of possible values of a corresponding data item in the packet for which the rule applies, and rule ranges defined in different rule sets correspond to a common set of data items. Independent item searches are performed for respective data items in the packet corresponding to rule ranges defined in the rule sets. The item search for a data item comprises selecting a range identifier corresponding to the value of the data item from a predetermined set of range identifiers for that data item. This set of range identifiers indicates, for all possible values of the data item, which of the rule ranges corresponding to the data item in the rule sets a value intersects.

Abstract: Methods and apparatus are provided for classifying data packets in a data processing device according to a set of processing rules, wherein, for each of a predetermined group of data items in each packet, each rule defines a rule range indicating a range of possible values of the corresponding data item for which that rule applies.

Abstract: The present invention discloses a memory sharing mechanism based on priority elevation. In accordance with the present invention, there is provided an apparatus and method for transporting packets of data in a communication device, wherein each packet is assigned one of several priorities and received based on memory state information. The method comprises the steps of storing the received packets in a memory and modifying the assigned priority of any of the packets causing congestion within the memory.

Abstract: The present invention discloses a memory sharing mechanism based on priority elevation. In accordance with the present invention, there is provided an apparatus and method for transporting packets of data in a communication device, wherein each packet is assigned one of several priorities and received based on memory state information. The method comprises the steps of storing the received packets in a memory and modifying the assigned priority of any of the packets causing congestion within the memory.

Abstract: The present invention discloses a scalable flow-control mechanism. In accordance with the present invention, there is provided a switching device for transporting packets of data, the packets being received at the switching device based on flow-control information, the device comprising a memory for storing the packets, a credit counter coupled to the memory for counting a credit number of packets departing from the memory, and a scheduler unit coupled to the credit counter for deriving the flow-control information in response to the credit number. Moreover, a switching apparatus and a method for generating flow-control information is disclosed.

Abstract: The present invention discloses a scalable flow-control mechanism. In accordance with the present invention, there is provided a switching device for transporting packets of data, the packets being received at the switching device based on flow-control information, the device comprising a memory for storing the packets, a credit counter coupled to the memory for counting a credit number of packets departing from the memory, and a scheduler unit coupled to the credit counter for deriving the flow-control information in response to the credit number. Moreover, a switching apparatus and a method for generating flow-control information is disclosed.

Abstract: A system and method for unifying access to a physical memory by operations using virtual addresses of the same virtual address space are provided. The operations may be generated by at least one central processing unit (CPU operations) and/or by at least one IO device (IO operations). The system may include a bus arranged to transfer data and virtual addresses of the same virtual address space from the central processing unit (CPU) and the IO device to a unified memory management unit (UMMU), a unified memory management unit (UMMU) arranged to translate the virtual addresses to physical addresses, and to protect the physical memory from illegal access attempts of the CPU operations and the IO operations. The system may further include a memory controller arranged to manage access to the physical memory. The access is done by using physical addresses.

Abstract: Methods and apparatus are provided for classifying data packets in data processing systems. A first packet classification method determines which of a plurality of predefined processing rules applies to a data packet, where each rule is associated with a range of possible data values in each of a plurality of dimensions (X,Y) corresponding to respective data items in the packet format. For each dimension (X,Y), it is determined which of a set of predefined basic ranges contains the corresponding data value (I1, I2) from the packet, where the basic ranges correspond to respective non-overlapping value ranges between successive rule range boundaries in the dimension. For the basic range so determined for each dimension, a corresponding basic range identifier is selected from a set of predefined basic range identifiers corresponding to respective basic ranges in that dimension.

Abstract: The present invention discloses a method and apparatus for transmitting incoming packet data via a data bus to a memory unit and transmitting outgoing packet data from the memory unit to a communication link via the data bus. The method for transmitting packet data via a data bus to a memory unit comprises the steps of receiving a stream of packet data; storing the received packet data in a buffer unit; and in response to the stored packet data, transmitting a burst of packet data to the memory unit, wherein the size of the burst of packet data depends on the properties of the data bus.

Abstract: Methods and apparatus are provided for classifying data packets in a data processing device according to a set of processing rules, wherein, for each of a predetermined group of data items in each packet, each rule defines a rule range indicating a range of possible values of the corresponding data item for which that rule applies.

Abstract: Methods and apparatus are provided for classifying data packets in a data processing device. In one aspect, packets are classified according to a plurality of sets of processing rules. Each rule defines a plurality of rule ranges, each rule range indicating a range of possible values of a corresponding data item in the packet for which the rule applies, and rule ranges defined in different rule sets correspond to a common set of data items. Independent item searches are performed for respective data items in the packet corresponding to rule ranges defined in the rule sets. The item search for a data item comprises selecting a range identifier corresponding to the value of the data item from a predetermined set of range identifiers for that data item. This set of range identifiers indicates, for all possible values of the data item, which of the rule ranges corresponding to the data item in the rule sets a value intersects.

Abstract: A real-time load-balancing system for distributing a sequence of incoming data packets emanating from a high speed communication line to a plurality of processing means, each operating at a capacity that is lower than the capacity of the high speed communication line; the system according to the invention comprises: a parser capable of extracting a configurable set of classifier bits from the incoming packets for feeding into a compression means; the compression means is capable of reducing a bit pattern of length K to a bit pattern having a length L which is a fraction of K; a pipeline block for delaying incoming packets until a load balancing decision is found, and an inverse demultiplexer for receiving a port identifier output from said compression means as selector and for directing pipelined packets to the appropriate output port.

Abstract: The present invention discloses a memory sharing mechanism based on priority elevation. In accordance with the present invention, there is provided an apparatus and method for transporting packets of data in a communication device, wherein each packet is assigned one of several priorities and received based on memory state information. The method comprises the steps of storing the received packets in a memory and modifying the assigned priority of any of the packets causing congestion within the memory.

Abstract: The present invention discloses a scalable flow-control mechanism. In accordance with the present invention, there is provided a switching device for transporting packets of data, the packets being received at the switching device based on flow-control information, the device comprising a memory for storing the packets, a credit counter coupled to the memory for counting a credit number of packets departing from the memory, and a scheduler unit coupled to the credit counter for deriving the flow-control information in response to the credit number. Moreover, a switching apparatus and a method for generating flow-control information is disclosed.

Abstract: Methods and apparatus are provided for classifying data packets in data processing systems. A first packet classification method determines which of a plurality of predefined processing rules applies to a data packet, where each rule is associated with a range of possible data values in each of a plurality of dimensions (X,Y) corresponding to respective data items in the packet format. For each dimension (X,Y), it is determined which of a set of predefined basic ranges contains the corresponding data value (I1, I2) from the packet, where the basic ranges correspond to respective non-overlapping value ranges between successive rule range boundaries in the dimension. For the basic range so determined for each dimension, a corresponding basic range identifier is selected from a set of predefined basic range identifiers corresponding to respective basic ranges in that dimension.