Abstract: A network event indicator system and corresponding method are described. The system includes an event rate classifier and an indicator drive state machine. The event rate classifier receives an event signal representing timing of a network event during a predetermined sample period and transmits an event rate signal. The indicator drive state machine receives the event rate signal and generates a drive indicator signal based on the received event rate signal.

Abstract: A method for remedying data corruption in a first circuit, which may be a CAM or a TCAM. The method includes providing a RAM circuit external to the first circuit, the RAM circuit being configured for storing error detection information for data stored in the first circuit. The method also includes scrubbing the data stored in the first circuit during scrubbing cycles of the first circuit. The scrubbing corrects stored bit patterns read from the first circuit that fail an error detection test using error detection information corresponding to individual ones of the stored bit patterns. In an embodiment, ECC may be employed for the error detection test and also to correct any single bit error found.

Abstract: A method for checking expected network traffic is disclosed. The method for checking expected network traffic includes accessing pre-registered expected results of a network traffic checking exercise that include expected packet content verification information for individual packets of the network traffic. In addition, the method includes accessing network traffic where individual packets of the network traffic include actual packet content verification information. Individual packets are identified that have expected packet content verification information that does not match their actual packet content verification information and individual packets are identified that have expected packet content verification information that does match their actual packet content verification information.

Abstract: A method for remedying data corruption in a first circuit, which may be a CAM or a TCAM. The method includes providing a RAM circuit external to the first circuit, the RAM circuit being configured for storing error detection information for data stored in the first circuit. The method also includes scrubbing the data stored in the first circuit during scrubbing cycles of the first circuit. The scrubbing corrects stored bit patterns read from the first circuit that fail an error detection test using error detection information corresponding to individual ones of the stored bit patterns. In an embodiment, ECC may be employed for the error detection test and also to correct any single bit error found.

Abstract: One embodiment disclosed relates to a method of mirroring network traffic. A data packet is received by a network device, and an algorithm including randomization is applied to determine whether the data packet is selected to be mirrored. The packet is sent to a destination port, and if the data packet is selected to be mirrored, then the packet is also sent to a mirror port. Another embodiment of the invention relates to a networking device. The networking device includes at least a plurality of ports, a switching/routing engine, and a mirroring engine. The plurality of ports receive and transmit packets therefrom, and the switching/routing engine is coupled to the ports for transferring the packets therebetween. The mirroring engine is configured to apply an algorithm including randomization to select data packets for mirroring. Other embodiments are also disclosed.

Abstract: One embodiment disclosed relates to a content addressable memory (CAM) supporting multiple width entries. The CAM includes a plurality of rows for storing bits in an array, and at least one width bit reserved in every row to indicate a width of an entry. At least two comparand registers are included, each comparand register configured to compare bits with a different subset of the rows in the array. Another embodiment disclosed relates to a method of searching a content addressable memory (CAM) supporting multiple width entries. A search word of a supported width is received, and a determination is made as to the width of the search word. Reserved width bits in comparand registers are set to indicate the width of the search word. The search word is loaded into the comparand registers, and a comparison operation is executed. Other embodiments are also disclosed.

Abstract: One embodiment disclosed relates to a method of processing a packet sent to a provider network. The packet is received via a user port of an edge switch of the network. Forwarding and routing by the edge switch is determined based on a user VID. A provider VLAN tag, including a provider VID, is inserted into the packet prior to transmission of the packet via a provider port of the edge switch.

Abstract: A dual-connection option allows preservation of network connectivity to a device or path by providing a second, redundant connection which takes over if a first connection fails. One goal is to provide communication with all critical devices at all times. If the ability to communicate with a device is lost because part of the connection to the device or the device itself has been destroyed, recovery from such loss is provided. The invention is preferably embodied in a particular implementation of the proposed Redundant Links standard, and satisfies the requirements of the proposed IEEE 802.12 standard, while adding specific enhancements to the proposed standard, such as storing and/or reporting conditions that lead up to a failure; accommodating minor, temporary disruptions; allowing status inquiries with regard to a redundant link while maintaining a primary connection; and continuing testing the redundant link after an initial verification.

Abstract: A method for transmitting data packets, grouped as data octets, over a LAN having a central hub linked to each of a plurality of network nodes via a physical medium consisting of four pairs of unshielded twisted pair (UTP) cable. The transmission method sequentially divides the data into data quintets. The quintets are then arranged into blocks of data quintets and sequentially distributed into four individual serial code streams. The four serial code streams are sequentially scrambled to produce four streams of randomized quintets. The randomized data streams are sequentially block encoded into 6-bit symbol data which are then transmitted using NRZ modulation across the network by transmitting each data stream over one of said pairs of cable.

Abstract: A method provides for a first network node in a plurality of network nodes to transmit a data packet to a hub. The hub and the network nodes are interconnected within a local network system. Control signals are exchanged between the first network node and the hub. The exchange of control signals is done in a first signal frequency range. A data packet is sent from the first network node to the hub. The data packet is sent using data signals within a second signal frequency range. The first signal frequency range and the second signal frequency range do not overlap.

Abstract: A method provides for a first network node in a plurality of network nodes to transmit a data packet to a hub. The hub and the network nodes are interconnected within a local network system. Control signals are exchanged between the first network node and the hub. The exchange of control signals is done in a first signal frequency range. A data packet is sent from the first network node to the hub. The data packet is sent using data signals within a second signal frequency range. The first signal frequency range and the second signal frequency range do not overlap.

Abstract: A method for transmitting data packets, grouped as data octets, over a LAN having a central hub linked to each of a plurality of network nodes via a physical medium consisting of four pairs of unshielded twisted pair (UTP) cable. The transmission method sequentially divides the data into data quintets. The quintets are then arranged into blocks of data quintets and sequentially distributed into four individual serial code streams. The four serial code streams are sequentially scrambled to produce four streams of randomized quintets. The randomized data streams are sequentially block encoded into 6-bit symbol data which are then transmitted using NRZ modulation across the network by transmitting each data stream over one of said pairs of cable.