Abstract: A deterministic routing table includes a set of hash circuits and a CAM. The routing table searches for the longest matching destination address stored in any of the hash circuits and the CAM, if any, and outputs an output pointer associated with that destination address within a fixed predetermined time.

Abstract: A packet processing device has a search engine module including an associative memory for transferring a packet on the basis of an entry mapping to route information, a first processor taking charge of a pre-search process before a process of the packet to the search engine module, and a second processor taking charge of a post-search process for executing a process of routing the packet on the basis of a search result of the search engine module. In this architecture, the packet processing device further has a table used for transferring and receiving information between the first processor in charge of the pre-search process and the second processor in charge of the post-search processor, and identifying information in a specified field of the table is transferred through the search engine module as a transparent medium.

Abstract: A multipath processing architecture that allows multipath packets to be distributed across multiple paths using a hash function and a modulo-arithmetic-based mapping function is disclosed. In one embodiment, the multipath processing architecture is implemented as part of a packet classification engine of a network node.

Abstract: The present invention provides methods for identifying and tracking data packets across a network. Specifically, network monitoring devices are configured to identify particular data packets or traffic flows at different points in a network by conversation fingerprinting. Conversation fingerprinting involves creating a unique identifier based on an invariant portion of one or more data packets in a traffic flow. An equivalency test is then performed between two identifiers from different monitoring devices to determine if the same data packet is received at two or more network monitoring devices. In order to reduce the probability of mismatches, additional heuristics may be applied based on additional attributes of the data packet or conversation. If a match occurs, then the timestamps of the two identifiers are compared to determine the point-to-point network transit latency between the two network monitoring devices.

Abstract: A method and system for converting a plurality of ranges of values for a plurality of packet classification rules in a computer system is disclosed. The plurality of ranges exists in at least one dimension. The method and system include mapping each of the plurality of ranges to a plurality of nonoverlapping prefixes. The method and system also include mapping the plurality of nonoverlapping prefixes to a plurality of overlapping prefixes corresponding to the plurality of ranges.

Abstract: An embodiment of the invention provides a mechanism for measuring the performance characteristics of data sent across any communication path configured to carry data between two or more computational devices (e.g., local area networks, wide area network, virtual private networks, wireless networks, or any other type of interconnect mechanism). In a test environment, processing speed is a critical part of producing test equipment that can process network protocol data in real-time. Embodiments of the invention provide network test equipment with a methodology for performing enough lookup processing operations to keep up with the real time frame rates of a gigabit Ethernet network. This is accomplished in accordance with one embodiment of the invention by improving the performance of the connection lookup processor in test devices.

Abstract: The present invention discloses a packet redirection method for a function programmable network processor for processing packets based upon a user's requirements or intention.

Abstract: Incoming communications received by call centers and the like are routed to one or more alternative call centers based on a comparison of Match Rates and Expected Wait Times. Such routing helps improve the overall load balancing of a call center or network of call centers while increasing the effectiveness and controlling the costs of handling incoming communications.

Abstract: Methods and systems for re-routing a connection through an explicitly routed network. The methods involve initially re-routing the connection to a reduced constraint connection through the network; establishing a fully constrained path through the network; subsequently re-routing the connection to the fully constrained connection through the network.

Abstract: A fast masked search for data having arbitrary length can be achieved using a plurality of fixed-length masked search function sections by a packet address search method, which includes the steps of dividing a search field in a packet into a plurality of sub-fields each being searchable at one time; performing a masked search for a match with each sub-field, and obtaining matched sub-entry identifiers as a primary search; generating a combination of the plurality of sub-entry identifiers obtained by the primary search; and performing a search for a match with the combination of the plurality of sub-entry identifiers and obtaining an entry identifier as a secondary search.

Abstract: Described herein is a method and apparatus for sharing connection state information between multiple processing elements.

Abstract: A method of managing a network switch. The method having the first step of detecting a status of a set of physical ports on an interface card in the network switch. Then, determining if the status is in a first state that indicates that all physical ports in the interface card are inaccessible. If the status is in the first state, then accepting all traffic for the set of physical ports. Also disclosed is an apparatus for performing the method.

Abstract: A system, method, and data structure are delineated for use in data storage and retrieval. An array of records stored in shared memory contains data entries, and associated hash codes computed from a predetermined hash function. A search request, consisting of one or more data entries, uses the same hash function to generate user codes. The records are searched to find one with hash codes that equal the user codes. This search involves comparisons of native data type entry, which are much faster than character string comparisons. Only after a record is identified with hash codes matching the user codes will a more time-consuming comparison be made between the selected record and the respective data entries of the search request.

Abstract: A method for performing flow based address hash transformation in a network device to generate hash pointers. The method includes the steps of receiving a pair of addresses (source address input and destination address input) corresponding to one direction of a data flow. The destination address input is modified by using a rotation operation. Respective hash operations are subsequently performed on the source address input and modified destination address input. The rotation operation performed on the destination address input prevents aliasing between the hash results for the forward direction of a data flow and the reverse direction, thereby preventing hash pointer collisions.

Abstract: A method for performing a parallel hash transformation in a network device to generate a hash pointer for an address input. The method includes the step of receiving an address input. The address input is apportioned among a plurality of hashing units. The hashing units are configured to operate in parallel. A hash transformation is executed on the apportioned address inputs in parallel, resulting in a corresponding plurality of hashing unit outputs. The hashing unit outputs are combined to generate a hash result corresponding to the address input.

Abstract: The invention provides a system and method for sharing packet traffic load among a plurality of possible paths. Each packet is associated with a flow, and a hash value is determined for each flow, so as to distribute the sequence of packets into a set of hash buckets. The hash value has a relatively large number of bits, but is divided by the number of possible paths so as to achieve a relatively small modulus value; the modulus value is used to index into a relatively small table associating one selected path with each entry. The modulus value is determined by a relatively small amount of circuitry, simultaneously for a plurality of moduli, and one such modulus value is selected in response to the number of possible paths.

Abstract: The present invention is directed to a facility for classifying network packets. The classified network packets each contain a source address, a source port number, a destination address, and a destination port number. The facility first sums the source address, the source port number, the destination address, and the destination port number contained by the packet. The facility then determines the modulo remainder of the sum over a constant predetermined value. The facility uses the determined modulo remainder to classify the packet into a class of packets predicted to relate to the same network session.

Abstract: A method of triggering reroutes in an ATM network based on a call optimization value being reduced beyond a predefined threshold. The method utilizes a signaling element in the SETUP message called a PNNI optimization reservation signaling element that includes an optimization type, value and percentage. A switch accumulates the optimization value and passes this value to the next node along the path. In addition, the hardware in the node is configured to measure and monitor the optimization value. The optimization value is monitored for changes that exceed the predefined optimization percentage. When this is detected, the software calculates a reroute. If the new route is better than the current route and is within the optimization percentage constraints, a reroute is performed using the newly calculated route. The reroute procedure provided by the ATM Forum can be used to implement the reroute.

Abstract: The invention provides a method and system for switching in networks responsive to message flow patterns. A message “flow” is defined to comprise a set of packets to be transmitted between a particular source and a particular destination. When routers in a network identify a new message flow, they determine the proper processing for packets in that message flow and cache that information for that message flow. Thereafter, when routers in a network identify a packet which is part of that message flow, they process that packet according to the proper processing for packets in that message flow. The proper processing may include a determination of a destination port for routing those packets and a determination of whether access control permits routing those packets to their indicated destination.

Abstract: An apparatus, a search tree structure, methods and computer devices for constructing and using the structure to efficiently accomplish policy based service differentiation in packet networks is presented. This invention reduces the number of steps performed to implement packet classification. It uses a method of preprocessing a given set of policy rules by modeling the conditions in the rules as multidimensional hyper-cubes, a simple and compact search tree is constructed. Using this search tree, packet classification is achieved determining all applicable policies for a packet with a few compare and branch instructions.

Abstract: A novel method of data forwarding is provided in a network switch having multiple ports including at least one backbone port for data communications with backbone network nodes. Destination information of a received data packet is compared with a predetermined set of address data in an address table. If the packet's destination information is not found in the address table, the received data packet is forwarded to the backbone port. Further, the source address information of the received data packet may be compared with the address table. In a regular mode of operation, if the packet's source address information is not found in the address table, this information is added to the address table. However, in a backbone mode of operation, the address information of a data packet received from the backbone port is prevented from being added to the address table. The switch may have backbone ports provided for multiple VLANs supported by the switch.

Abstract: Apparatus, and an associated method, for facilitating exchange of configuration indicia associated with a mobile node operable in a radio communication system. The mobile node is dynamically-configurable, and includes a logic tree. The indicia is provided to a network manager responsive to request therefore or upon initiation by the mobile node. When initiated at the network, a request message generator located at a network manager generates a get message to request that certain configuration indicia be provided to the network manager. The mobile node, upon delivery of the get message thereto, retrieves the requested information, at a selected level of detail, and returns the indicia to the network manager.

Abstract: A network switch, configured for performing layer 2 and layer 3 switching in an Ethernet (IEEE 802.3) network without blocking of incoming data packets, includes a network switch port having a port filter configured for evaluating an incoming data packet on an instantaneous basis. The filter is configured for determining the presence of prescribed layer 3 information in a received data packet. The port filter also signals a switch fabric of the network switch to learn the IP-MAC association of the data packet. The port filter determines whether or not the data packet is part of the data traffic between connected subnetworks of the network switch. With the port filter in the above configuration, the network is enabled to perform layer 3 and layer 2 switching for 100 Mbps and gigabit networks without blocking in the network switch.

Abstract: The present invention provides an address analysis method for the next generation integrated network service. The address analysis method makes it possible to establish an outgoing or incoming call service in all kinds of address schemes while the integrated network interworks with a wired/wireless integrated network.

Abstract: In a method and apparatus for performing multiprotocol switching and routing, incoming data packets are examined and the flow (i.e., source and destination) with which they are associated is determined. A flow table contains forwarding information that can be applied to all the packets belonging to the flow. If an entry is not present in the table for the particular flow, the packet is forwarded to the CPU to be processed. The CPU can then update the table with new forwarding information to be applied to all future packets of the same flow. When the forwarding information is already present in the table, packets can be forwarded at wire-speed. A dedicated ASIC is preferably employed to contain the table, as well as the engine for examining the packets and forwarding them according to the stored information. Decision-making tasks are thus more efficiently partitioned between the switch and the CPU so as to minimize processing overhead.

Abstract: In order to make it possible for communications quality required for communication to be selected optimally in conformity with the states of a plurality of networks, which network is to be used for communication is selected based upon a plurality of communications qualities and communication is performed upon reserving the communications resources of the selected network.

Abstract: A destination address retrieving system generates a retrieval key from a header information of a packet and performs a retrieval to an address information table based on the key and receives a returned value. If the returned value indicates the presence of any internal header, then the address retrieving unit further generates another retrieval key from an internal header information of the packet, for performing another retrieval to another address information table.

Abstract: An integrated circuit monitors the most active traffic flow rates on a communications network by using a leaky bucket model having a variable fill rate. As a switch receives packets, the packet identifications are sampled. A sampled packet identification is compared to record identifications in a table of identifications. If the sampled and record identifications match, an activity value for the packet identification is increased by an amount inversely proportional to an activity value associated with the record identification. If the sampled and record identifications do not match, the activity value is decreased. Record identifications are removed from the table when the activity value decreases to a specified level. New sampled identifications are added to the table if empty records exist.

Abstract: A method is disclosed for establishing a switched virtual circuit in a digital network having network nodes with static routing tables. The static routing tables contain at least primary and alternate routing data. When a node is unable to forward a call over its outgoing primary route due to congestion or physical failure and its alternate route is the same as the route on which a call setup request arrived, it clears the call at that node and sends a crankback message to the preceding node, which responds to the crankback message to attempt to dynamically re-route the call over the alternate route stored in the routing table of the preceding node. If the attempt is unsuccessful, it sends the message back to the next preceding node and so on.

Abstract: In one embodiment, a method for efficiently classifying packets for a multi-processor/mutli-thread environment is provided. The method initiates with receiving a packet. Then, header information is extracted form the received packet. Next, a first hash value is calculated. Then, a field of interest in a lookup table is determined from the first hash value. Next, a second hash value is calculated. Then, the second hash value is compared to stored hash values in the field of interest of the lookup table to determine a match between the second hash value and one of the values in the field of interest of the lookup table. If there is a match, the received packet is transmitted to a processor corresponding to the one of the values in the row location of the lookup table. A network interface card and a system for efficiently classifying packets in a multicore/multithread environment are also provided.

Abstract: Distributing packets from an input link to multiple output links involves categorizing each incoming packet, selecting a mapping algorithm based on the packet category, and using the selected mapping algorithm for each packet to determine an output link for the respective packet. If packets are from a category that requires the order of the packets to be maintained, then the selected mapping algorithm causes packets from the same set of packets to be distributed to the same output link. If packets are from a category that does not require the order of the packets to be maintained, then the selected mapping algorithm can cause packets to be distributed more evenly among the multiple output links. Hashing can be used to distribute in-order packets from the same set to the same output link. Load balancing and round-robin distribution can be used to distribute out-of-order packets more evenly across the output links.

Abstract: An apparatus and method for an advanced multiplexing technique to allow a single host to support multiple Internet Protocol (IP) queue pairs with little or no overhead are provided. With the apparatus and method, after a queue pair is created, Internet Protocol filter attributes and values are set up for the queue pair through value added features to the standard InfiniBand “QP Modify” method. The IP filters are used during normal operations to determine which queue pair is associated with an incoming packet. During normal operations, when a channel adapter receives an Internet Protocol (IP) over InfiniBand (IB) packet, it uses one or more of several fields in the packet's transport and/or network header to determine which queue pair shall receive the packet. Thus, the host channel adapter uses the IP filters to route incoming packets to the appropriate queue pair and thereby allow more than one queue pair to be used to support IP.

Abstract: Methods, systems, and apparatus are provided to enable access to mobile and voice over IP (VoIP) telephone networks with a mobile handset. A VoIP gateway for the VoIP telephone network is provided. A cable modem allows communication between the handset and the VoIP telephone network via the VoIP gateway. A local network connects the handset to the VoIP gateway. The mobile handset determines whether it is within range of the local network. If the handset is within the range of the local network, data traffic may be routed to and from the handset via the VoIP telephone network. If the handset is outside of the range of the local network, data traffic may be routed to and from the handset via the mobile telephone network. The data traffic may comprise telephony data traffic and/or Internet protocol (IP) data traffic.

Abstract: A method and apparatus that constructs a “router database” and then uses the database to determine a longest match between a piece of target data, such as an address in a packet to be routed, and the database. The database contains a comparison table having a plurality of entries. In a first embodiment, each entry has up to k values, where 2<=k<=N, where N is a number of comparison values in the database. In a second embodiment, each entry has up to k−1 values. During operation, various ones of the comparison table entries are loaded and compared to the address to determine a longest matching prefix in the router database. The comparison can be done in parallel.

Abstract: The invention provides a method and system for routing information lookup for packets using routing protocols such as IP or IP multicast (IGMP), or MPLS (multiprotocol label switching, also known as tag switching or label switching) or MPLS multicast, in which both the destination address and the length of that destination address are matched using a lookup table having separate entries for selected addresses and their lengths, which can be accessed in parallel for multiple representations of destination addresses, and in which the input interface associated with the packet is included in the information used for matching.

Abstract: A packet receiving circuit 11 splits the packet received from a transmission channel 1 into a fixed length of cells and outputs the cells, a search key extracting circuit 12 extracts a predetermined search key from the above-mentioned cells, a CAM 13 performs retrieval based on the above-mentioned search key and outputs a memory address corresponding to the search key, a matching entry address receiving and associative data address transmitting circuit 14 calculates the memory address of an associative data memory 15 based on the above-mentioned memory address and outputs the information stored in the associative data memory 15 as associative data, a search result (associative data) receiving circuit 16 receives the above-mentioned associative data and performs header updating and destination address of the above-mentioned cells, and a packet transmitting circuit 17 outputs the above-mentioned cells in the form of a packet to a transmission channel 2.

Abstract: A method for distributing addressed data packets from an input channel to a multiplicity of packet queues includes receiving said addressed data packets and, responsive to first hashed addresses, distributing the addressed data packets to said queues in accordance with said first hashed addresses. A first hash function is applied to selected address data of each of said addressed data packets to produce said first hashed addresses. At the same time a succession of different hash functions is applied to said selected address data in each of the packets to produce second hashed addresses and occurrences of each of the second hashed addresses are counted so as to obtain for each of said different hash functions a respective one of a plurality of set of counts, each such set representing the distribution of said packets that would occur in said queues if the respective one of the different hash functions had been applied to said addressed data packets.

Abstract: An Internet address pre-lookup method, suitable for an Internet packet delivery system using a routing table and hash table. First, a pre-lookup table including a plurality of pre-lookup bits in the system is provided, each pre-lookup bit corresponding to a converting address, when any Internet address corresponding to the converting address exists in the routing table, then the pre-lookup bit corresponding to the converting address is set as valid. A packet including a destination address is received, and the pre-lookup bit corresponding to the converting address the same as the valid address of the destination address is checked in the pre-lookup table. When the pre-lookup bit corresponding to the converting address the same as the valid address of the destination address is invalid, a default process is directly performed on the packet.

Abstract: The present invention relates to a packet transfer communication device. More particularly, the present invention relates to a congestion control unit to designed handle communication at high speed by reducing a load of congestion processing conducted in a core router and an edge router.

Abstract: A multi-level table is searched for an item in an item database matching a search key. For example, a multi-level search table is searched for an identifier of an Internet Protocol prefix stored in a prefix database which most closely matches an Internet Protocol address. The search table may be modified in response to changes to the item database while the table is being searched. Default item identifier tables may be used to store default item identifiers which reduce the complexity of update operations.

Abstract: A cell scheduling and forwarding technique for an input-buffered N×N non-blocking crossbar switch which provides worst-case intra-switch port cell forwarding service delays which are bounded by the duration of N cell forwarding timeslots. This scheduler is further enhanced to support efficient rate based forwarding service.

Abstract: A communication system having a proxy architecture is disclosed. The system includes a platform that provides performance enhancing functions. The platform includes a spoofing apparatus that routes the information within the communication system. The spoofing apparatus receives spoofing selection and spoofing parameters from the platform and maintains the current parameters in one or more spoofing profiles. The spoofing apparatus routes packets of information throughout the communication system based on the spoofing selection and/or spoofing profile. The spoofing apparatus may also compensate for maximum segment size mismatches during the routing of information. This compensation may include dynamically resizing data segments or disabling three-way handshake spoofing. The above arrangement has particular applicability to a bandwidth constrained communication system, such as a satellite network.

Abstract: The present invention is directed to a high speed packet switching network and, in particular to a method and system for minimizing the time to establish a connection between an origin and a destination node. A path calculated at the time the connection is requested is recorded in a Routing Database and updated each time a modification occurs in the network. Furthermore, alternate paths for supporting non-disruptive path switch on failure or preemption, and new paths towards potential destination nodes can be calculated and stored when the connection set up process is idle. These last operations are executed in background with a low processing priority and in absence of connection request.

Abstract: New switching technology relies upon state information for providing a previously unavailable degree of quality of service. In particular, by providing the ability to give service guarantees to uniquely identifiable sets of packets (“micro-flows”), different qualities of service can be offered for each transmission. The QoS associated with each micro-flow is characterized by a set of descriptors. These descriptors are communicated to each switch by the first packet of the micro-flow associated with the descriptors.

Abstract: The invention provides for hardware processing of ACLs and thus hardware enforcement of access control. A sequence of access control specifiers from an ACL are recorded in a CAM, and information from the packet header is used to attempt to match selected source and destination IP addresses or subnets, ports, and protocols, against all the ACL specifiers at once. Successful matches are input to a priority selector, which selects the match with the highest priority (that is, the match that is first in the sequence of access control specifiers). The specified result of the selected match is used to permit or deny access for the packet without need for software processing, preferably at a rate comparable to wirespeed. The CAM includes an ordered sequence of entries, each of which has an array of ternary elements for matching “0”, “1”, or any value, and each of which generates a match signal.

Abstract: A header conversion device allowing reduced amount of hardware and memory and high-speed line switching is disclosed. In an ATM switching device having redundant incoming line systems, a header conversion table stores a set of header conversion information for one of the redundant incoming line systems. A header converter converts the header of an ATM cell received from each of the redundant incoming line systems by referring the same set of header conversion information.

Abstract: A network switch for network communications is disclosed. The switch includes a first data port interface supporting at least one data port transmitting and receiving data at a first data rate and a second data port interface supporting at least one data port transmitting and receiving data at a second data rate. The switch also has a CPU interface configured to communicate with a CPU and a memory management unit for communicating data from at least one of the first and second data port interfaces and a memory. It also includes a communication channel for communicating data and messaging information between the first and second data port interfaces and the memory management unit and a plurality of lookup tables, including an address resolution lookup table and a VLAN table.