Abstract: A datagram relaying apparatus includes a plurality of protocol terminating units, and a destination determining processor. The destination determining processor includes a path selecting section which determines a transfer destination route for a stream of packets received from any of the protocol terminating units. The path selecting section determines whether or not transfer of the received stream of packets to the transfer destination route is in an inhibition state, and selects another transfer destination route when the transfer of the packet to the transfer destination route is in the inhibition state.

Abstract: Techniques are described for aggregating multiple media packets to improve end-to-end bandwidth efficiency. The techniques include using an RTP aggregation protocol that is not sensitive to packet loss to aggregate multiple media packets under a single header. According to the RTP aggregation protocol, the single header for an aggregated media packet comprises a version field, a zero field, a sequence number field and a trunk ID field. The single header encapsulates the aggregated payload, which is an aggregation of Real-Time Protocol (RTP) segments. An RTP segment either has a compressed format or an uncompressed format. The uncompressed RTP segment includes the complete uncompressed RTP packet copied from the original User Datagram Protocol (UDP) packet. The compressed RTP segment includes the payload of the original RTP rather than the complete original RTP packet.

Abstract: A device facilitates offset independent message filtering, and receives a filter registration request from a control software element, where the filter registration request includes at least a field name and a filter value. The device also identifies an offset value associated with the received field name, and filters a message based on the filter value and the identified offset value.

Abstract: A device may include a group of requestors issuing requests, a memory that includes a set of memory banks, and a control block. The control block may receive a request from one of the requestors, where the request includes a first address. The control block may perform a logic operation on a high order bit and a low order bit of the first address to form a second address, identify one of the memory banks based on the second address, and send the request to the identified memory bank.

Abstract: A method performed by a primary server includes receiving integrity criteria and sending a health check request to a secondary server based on the received integrity criteria. The method also includes receiving integrity information from the secondary server and checking the integrity information against the integrity criteria. The method further includes initiating a non-compliance action if the integrity information does not comply with the integrity criteria.

Abstract: A device includes a memory, flow table logic, sampling logic, and a processing unit. The memory is configured to store a flow table that stores, as a number of entries, statistics regarding a number of data flows. The flow table logic is configured to generate records corresponding to data flows for which entries are created in the flow table or removed from the flow table. The sampling logic is configured to select one of the data flows for sampling and sample initial data units for the one of the data flows. The processing unit is configured to receive the records generated by the flow table logic, receive the initial data units sampled by the sampling logic, analyze the initial data units to generate analysis results, correlate the records and the analysis results associated with a same one of the data flows, and store the correlated records and analysis results.

Abstract: A device stores forwarding information associated with fragments of a first data unit, stores information common to the fragments of the first data unit, receives fragments of a second data unit, and forwards the fragments of the second data unit based on the forwarding information of the first data unit and the information common to the first data unit.

Abstract: In general, techniques are described for packet queuing within ring networks. In accordance with the techniques, a network device of a ring network comprises a memory having a different queue for each order-dependent pair of the network devices. Each pair represents a different order-dependent combination of the network devices that includes an ingress network device that provides an ingress to the ring network and an egress network device that provides an egress from the ring network. The network device further comprises an interface for receiving a packet from a neighboring one of the plurality of network devices and a control unit that, in response to receiving the packet, stores the packet to one of the queues based on which network devices is the ingress and which network device is the egress for the packet. The control unit forwards the stored packet via the ring network according to a scheduling algorithm.

Abstract: A multi-chassis router allows an administrator to deliver commands from a single interface. Additionally, the multi-chassis router presents a software image consistent with that of a standalone router and uses commands and configurations consistent with those used by a standalone router. The multi-chassis router automatically distributes, processes and responds to administrator commands a single unit, minimizing time required to administer the multi-chassis router. In effect, an administrator does not need to account for the multiple chassis configuration, and an administrator familiar with the control and commands for a standalone router can use that knowledge to effectively control the operation of the multi-chassis router.

Abstract: An intermediate network device performs service aware path selection. For example, the intermediate network device comprises a network interface that receives network traffic and a control unit that couples to the network interface. The control unit comprises a storage medium that stores a first set of cost factors for a first path from the intermediate network device to another intermediate network device. The first set of cost factors includes at least one optimization cost factor corresponding to intermediate optimization capabilities available to the intermediate network device that offset other cost factors of the first set. The storage medium also stores a second set of cost factors for a second path between the devices. The control unit selects either the first path or the second path over which to forward the network traffic based on the first and second sets of cost factors.

Abstract: A chassis may include a front section that contains a first electronic circuit board oriented in a first plane, a rear section that contains a second electronic circuit board oriented in a second plane, where the first plane and the second plane are substantially orthogonal, a midplane dividing the front and the rear sections, and a fan tray assembly including a plurality of fans to cool both the first electronic circuit board of the front section and the second electronic circuit board of the rear section.

Abstract: A method performed by an I/O unit connected to another I/O unit in a network device. The method includes receiving a packet; segmenting the packet into a group of data blocks; storing the group of data blocks in a data memory; generating data protection information for a data block of the group of data blocks; creating a control block for the data block; storing, in a control memory, a group of data items for the control block, the group of data items including information associated with a location, of the data block, within the data memory and the data protection information for the data block; performing a data integrity check on the data block, using the data protection information, to determine whether the data block contains a data error; and outputting the data block when the data integrity check indicates that the data block does not contain a data error.

Abstract: A network device comprises a service card (e.g., a dynamic flow capture (DFC) service card) executing a communication protocol to receive, from one or more control sources, flow capture information specifying at least one destination and criteria for matching one or more packet flows. The network device includes a network interface card to receive a packet from a network, a packet replication module to replicate the packet, and a control unit to provide the replicated packet from the interface card to the DFC service card. The network device includes a filter cache that caches flow capture information recently received from the CSs. The network device may provide real-time intercept and relaying of specified network-based communications. Moreover, the techniques described herein allow CSs to tap packet flows with little delay after specifying flow capture information, e.g., within 50 milliseconds, even under high-volume networks.

Abstract: A device may store a first and second queue of packets, calculate an average queue size based on the number of packets in the first and second queues and discard a packet when the packet is a session creation packet and the calculated average queue size is greater than a threshold value.

Abstract: In general, the invention is directed to techniques of dynamically balancing network traffic load among multiple paths through a computer network. The techniques distribute and redistribute flows of network packets between different paths based on dynamically measured path bandwidth and loads of each flow. In distributing the flows, Quality of Service (QoS) bandwidth requirements of the flows may be maintained.

Abstract: A system provides congestion control in a network device. The system includes multiple queues, a dequeue engine, a drop engine, and an arbiter. The queues temporarily store data. The dequeue engine selects a first one of the queues and dequeues data from the first queue. The drop engine selects a second one of the queues to examine and selectively drop data from the second queue. The arbiter controls selection of the queues by the dequeue engine and the drop engine.

Abstract: A device may include first logic configured to receive a data unit and to receive a network policy. The device may include second logic configured to identify how the data unit will be handled by the network policy and to generate a result that includes information about how the data unit will be handled by the network policy.

Abstract: An apparatus and method are described for compensating for frequency and phase variations of electronic components by processing packet delay values. In one embodiment, a packet delay determination module determines packet delay values based on time values associated with a first and a second electronic component. A packet delay selection module selects a subset of the packet delay values based on the maximum frequency drift of the first electronic component. A statistical parameter determination module evaluates a first and a second parameter based on portions of the subset of packet delay values A validation module validates the parameters when each portion the subset of packet delay values includes a minimum of at least two packet delay values. An adjustment module compensates for at least one of a frequency variation and a phase variation of the first electronic component based on the parameters if the parameters are both validated.

Abstract: The invention provides a PVC switching control method for an ATM communication network which allows high speed changeover of a connection upon occurrence of/release from a trouble and is superior in reliability and maintenance facility and simple in control. A master PVC connection and an OAM connection are set between two ATM exchanges, and a bypassing PVC connection and an OAM connection prepared in advance for bypassing are set between the two ATM exchanges. If occurrence of/release from a trouble with and of the master PVC connection is recognized by the ATM exchanges using an OAM function, then the operative PVC connection is switched between the master PVC connection and the bypassing PVC connection.

Abstract: In a PPP terminating equipment connected with a switch fabric and terminating PPP link, the PPP terminating equipment has an LCP echo requirement detecting section detecting whether or not a received packet is the LCP echo requirement packet, and an LCP echo response producing section producing a response packet to the LCP echo requirement by rewriting the LCP header of the received LCP echo requirement packet. The PPP terminating equipment thereby produces and returns the response packet to the LCP echo requirement.