Abstract: A method and system for memory management in a network processing system provides for allocation of physical memory areas within network processors coupled to a control point processor by a bus. The allocation scheme provides a memory management layer without requiring a complete operating system interface and supports asynchronous completion of the allocation requests. Multicast allocation is supported allowing an allocation to be simultaneously requested on multiple network processors. The allocation mechanism returns a token, which may then be used to access the memory location via a protocol over the bus, and a single token may refer to an allocation made on several network processors where the actual physical addresses and memory configurations are different.

Abstract: Certain Layer 3 protocol data frames propagated on a network are typically processed by a control point (CP) in a network switch. The logical bridging and routing functions required in this processing typically entail network device address look-ups in routing tables and address databases. Using the CP to perform these look-ups is expensive in terms of processor cycles and memory. To offload the CP, the bridging functions are performed a network processor in the switch. The network processor has specialized software and hardware enabling it to perform the required database look-ups faster and more efficiently than the CP.

Abstract: Method and apparatus for receiving a data frame on a received port of a network switch. The data frame includes a source media access control (MAC) address for the first device, and a destination MAC address for a second device connected to another port of the network. The data frame is forwarded to a target port which is connected to the second device. The MAC address is learned locally at the target port which facilities communications for frames which later enter the target port and contain addresses previously learned from a received frame.

Abstract: A multicast processor minimizes the software resource needed to process multicast protocol and broadcast protocol for bridges and routers in a network processor based environment. The multicast forwarding processor receives multicast and broadcast Layer 2/Layer 3/Layer 4 (L2/L3/L4) frames from a network processor. During reception, a frame layer flag, a unicast/multicast flag, and a frame position flag are set. A multitask forwarding table is accessed, and the frame, unicast/multicast, and frame position flags are stored and updated. The frame, unicast/multicast, and frame position flags are then sent to a frame forwarding processor. The L2/L3/L4 frames are routed to an L2 learning processor. The L2/L3/L4 frames are received from the frame forwarding processor, and the L2/L3/L4 frames are sent to an L3/L4 processor for frame header modification. The modified L2/L3/L4 frames are received from said L3/L4 processor, and the modified L2/L3/L4 frames are sent to an L2 filter processor.

Abstract: A method and apparatus for processing network frames by embedding control information achieves an efficient frame processing system within a network processor (NP). The layer type of the frame can be quickly determined by the layer processing components of picocode running on the NP by examining control information that is written by ingress processing layers to produce a modified frame format. The frames are routed to appropriate layer processors and processing for certain layers may be bypassed if the picocode determines that no processing is required at that layer. The frame may also be discarded completely by any of the layer processors.

Abstract: A system for controlling multicast traffic in a multiprocessing system is disclosed. The multiprocessing system includes a general-purpose processor, a plurality of network processors and a switch fabric. The system comprises a multicast identifier (MID) manager to manage a distributed database of MIDs. The distributed database includes at least one compound MID. The at least one compound MID structure further comprises a plurality of MIDs representing at least two multicast groups. The system also includes a MID processor which traverses the at least one compound MID and resolves it into its associated simple MIDs. Accordingly, the present invention provides for a system and method for efficiently controlling multicast transmissions when different types of multicast groups are to receive the multicast transmissions. In this system and method a new type of multicast identifier (MID) is provided, a compound MID. The compound MID is a single MID but references multiple MIDs.

Abstract: In a distributed networking environment employing several general purpose processors (i.e., control point processors) for controlling one or more network processor devices, a mechanism for distributing processing across several general purpose processors and interface for configuring a network processor so that specific general purpose processors handle specific operations in a large networking environment, thus, reducing requirement for provisioning a plurality of protocol stacks on each general purpose processor.

Abstract: A method and system for performing aging of a memory in a computer system is disclosed. The memory contains a plurality of items. The method and system include purging the memory of a portion of the plurality of items each time an epoch equal to an aging variable has expired. The method and system further include providing the aging variable for a new epoch based on a performance of the memory in a previous epoch, including the aging variable of the previous epoch.