摘要:
A method and system for transmitting packets in a packet switching network. Packets received by a packet processor may be prioritized based on the urgency to process them. Packets that are urgent to be processed may be referred to as real-time packets. Packets that are not urgent to be processed may be referred to as non-real-time packets. Real-time packets have a higher priority to be processed than non-real-time packets. A real-time packet may either be discarded or transmitted into a real-time queue based upon its value priority, the minimum and maximum rates for that value priority and the current real-time queue congestion conditions. A non-real-time packet may either be discarded or transmitted into a non-real-time queue based upon its value priority, the minimum and maximum rates for that value priority and the current real-time and non-real-time queue congestion conditions.
摘要:
A method and system for transmitting packets in a packet switching network. Packets received by a packet processor may be prioritized based on the urgency to process them. Packets that are urgent to be processed may be referred to as real-time packets. Packets that are not urgent to be processed may be referred to as non-real-time packets. Real-time packets have a higher priority to be processed than non-real-time packets. A real-time packet may either be discarded or transmitted into a real-time queue based upon its value priority, the minimum and maximum rates for that value priority and the current real-time queue congestion conditions. A non-real-time packet may either be discarded or transmitted into a non-real-time queue based upon its value priority, the minimum and maximum rates for that value priority and the current real-time and non-real-time queue congestion conditions.
摘要:
A method and system for transmitting packets in a packet switching network. Packets received by a packet processor may be prioritized based on the urgency to process them. Packets that are urgent to be processed may be referred to as real-time packets. Packets that are not urgent to be processed may be referred to as non-real-time packets. Real-time packets have a higher priority to be processed than non-real-time packets. A real-time packet may either be discarded or transmitted into a real-time queue based upon its value priority, the minimum and maximum rates for that value priority and the current real-time queue congestion conditions. A non-real-time packet may either be discarded or transmitted into a non-real-time queue based upon its value priority, the minimum and maximum rates for that value priority and the current real-time and non-real-time queue congestion conditions.
摘要:
A method for dynamically adjusting the flow rate of a plurality of logical pipes that share a common output queue. In accordance with the method of the present invention, a minimum flow rate and a maximum flow rate are set for each of the pipes. Next a determination is made of whether or not excess queue bandwidth exists in accordance with the output flow rate of the shared queue. The determination of whether or not excess bandwidth exists comprises comparing the output flow rate of the shared queue with a pre-determined threshold queue output value. An instantaneous excess bandwidth signal has a value of 1 if there is excess bandwidth and is otherwise 0 if there is no excess bandwidth. In an alternate embodiment, the instantaneous excess bandwidth signal for a particular pipe is logically ANDed with one or more additional excess bandwidth signals to form a composite instantaneous excess bandwidth signal. In response to the existence of excess queue bandwidth, a flow rate of a pipe is linearly increased while in response to a lack of excess queue bandwidth, the flow rate of the pipe is exponentially decreased.
摘要:
A method and system for transmitting packets in a packet switching network. Packets received by a packet processor may be prioritized based on the urgency to process them. Packets that are urgent to be processed may be referred to as real-time packets. Packets that are not urgent to be processed may be referred to as non-real-time packets. Real-time packets have a higher priority to be processed than non-real-time packets. A real-time packet may either be discarded or transmitted into a real-time queue based upon its value priority, the minimum and maximum rates for that value priority and the current real-time queue congestion conditions. A non-real-time packet may either be discarded or transmitted into a non-real-time queue based upon its value priority, the minimum and maximum rates for that value priority and the current real-time and non-real-time queue congestion conditions.
摘要:
A method and system for controlling a plurality of pipes in a computer network is disclosed. The computer network includes at least one processor for a switch. The at least one processor has a queue. The plurality of pipes utilizes the queue for transmitting traffic through the switch. The method and system include allowing a minimum flow and a maximum flow to be set for each of the plurality of pipes and determining if excess bandwidth exists for the queue. The method and system also include linearly increasing a flow for a pipe of the plurality of pipes based on the minimum flow or the maximum flow if excess bandwidth exists and if the flow for the pipe of the plurality of pipes is less than the maximum flow for the pipe. The method and system also include exponentially decreasing the flow for the pipe of the plurality of pipes based on the minimum flow or the maximum flow if excess bandwidth does not exist and the flow is greater than the minimum flow for the pipe. Thus, the traffic through the queue is stable.
摘要:
A wire-speed forwarding platform and method for supporting multifield classification of a packet fragmented into a plurality of fragments in the wire-speed forwarding platform, comprising: receiving a fragment of the fragmented packet at the forwarding platform and deriving a key from one or more fields of the received fragment; and performing multifield classification of the received fragment by matching the key to a rule out of a plurality of rules, the rule comprising a plurality of fields including at least one field for specifying whether the received fragment's fragmentation characteristics are to be applied when performing the multifield classification.
摘要:
In a router comprising one or more network processing (NP) devices for routing data packets from a source NP device to a destination device via a switch fabric, with each network processing device supporting a number of interface ports, each port capable of interfacing with one or more data queues for receiving packets associated with a class-of-service characterizing the routing of the packets, a system and method for routing packets comprising: classifying a packet to be forwarded from a source NP device according to a particular class-of-service and determining outgoing interface port information of a destination NP device to forward the packet, the interface port having a pre-defined queue base address associated therewith; encoding a queue index offset for the packet associated with a particular class-of-service associated with the packet to be routed; forwarding the packet, queue index offset and outgoing interface port information to the destination NP; and, determining a queue identifier from the base address and transmitted queue index offset for indicating a particular queue by which the classified packet is to be forwarded, wherein the queue identifier is determined locally at the destination NP device forwarding the packet.
摘要:
A wire-speed forwarding platform and method for supporting multifield classification of a packet fragmented into a plurality of fragments in the wire-speed forwarding platform, comprising: receiving a fragment of the fragmented packet at the forwarding platform and deriving a key from one or more fields of the received fragment; and performing multifield classification of the received fragment by matching the key to a rule out of a plurality of rules, the rule comprising a plurality of fields including at least one field for specifying whether the received fragment's fragmentation characteristics are to be applied when performing the multifield classification.
摘要:
A controllable mechanism for by-passing Layer 4 (L4) classification is based on the insertion into a set of MAC rules in SA MAC lookup means a set of Layer 4 (L4) Skip Classification Flags. Routing is accomplished by selecting which rule to apply to the packet and reading the state of the corresponding L4 Skip Classification Flag. In response to a first state of said corresponding L4 Skip Classification Flag, performing an L4 classification followed by a routing of the data packet. In response to a second state of said corresponding L4 Skip Classification Flag, reading the state of a Global Classification Flag. In response to a first state of said Global Classification Flag, performing an L4 classification followed by a routing of said data packet. In response to a second state of said Global Classification Flag performing a routing of the data packet. The L4 Skip option change does not use the option change of reading the L4 Skip Classification Flag from the port table, whereas the second embodiment uses this option. The third and fourth embodiments are similar to the first and second embodiments but with the. addition of inserting into a set of Layer 3 (L3) rules in L3 lookup means a set of Layer 4 (L4) Classification Required Flags. The third embodiment does not use the option of reading the L4 Skip Classification Flag from the port table, whereas the fourth embodiment uses this option.