摘要:
A multi-layer network element (12) for forwarding received packets from an input port to one or more output ports (38) with quality of service. When output queues (54) exceed or meet a threshold value below the queue's capacity packets are randomly discarded. When the queue becomes full, the network element determines which flow caused the queue to overflow. The priority of that flow is lowered. In a multicast packet, the packet may have different priorities at each output port. Scheduling of multiple output queues at each output port uses a weight round robin approach that allocates a weight portion of packets to transmit at each time interval. A packet is not interrupted during its transmission, even if the weight portion is met during a packet's transmission. The excess number of bytes transmitted as a result of not interrupting the packet are accounted for in the next round.
摘要:
There is disclosed a scheduler, and a method, for scheduling a plurality of input flows to an output flow, comprising: means for allocating to each input flow a flow level and a threshold value, the flow level being indicative of the number of bits to be scheduled from the input flow, wherein the value of the flow level relative to the threshold value indicates whether the current scheduling of that input flow is sufficient to meet a necessary throughput for that input flow; means for increasing the value of each flow level by a predetermined amount; and means for selecting the input flow to be scheduled in dependence on the flow having a highest priority of those flows having a flow level greater than the respective threshold level, wherein there is further included means for, if no input flows have a flow level above the respectivethreshold level, increasing the flow level for each input flow having data to transmit by a second predetermined value.
摘要:
A method and a system for providing security to a network (12) by at least identifying an unauthorized user (20) who is attempting to gain access to a node (16) on the network (12), and preferably by then actively blocking that unauthorized user (20) from further activities. Detection is facilitated by the unauthorized user providing 'earmark', or specially crafted false data, which the unauthorized user (20) gathers during the information collection stage performed before an attack. The earmark is designed such that any attempt by The unauthorized user (20) to use such false data results in the immediate idenfication of the unauthorized user (20) as hostile, and indicates that an intrusion of the network (12) is being attempted. Preferably, further access to the network (12) is then blocked by diverting traffic from the unauthorized user (20) to a secure zone (32), where the activities of the unauthorized user can be contained without damage to the network (12).
摘要:
Various embodiments are disclosed for techniques to perform channel access decisions (315) and to select a transmit queue. These decisions may be performed, for example, based upon the age (305) and number (310) of packets in a queue. These techniques may allow a node to improve the length of data bursts transmitted by the node, although the invention is not limited thereto.
摘要:
A method for scheduling transmissions to a plurality of users in a communication network determines a satisfaction metric and a dissatisfaction metric for each user in a given timeslot that is to be used for a next scheduled transmission to one of the users. Each user is assigned a weight based on a value of at least one of the user's satisfaction metric, the user's dissatisfaction metric and a rate requested by the user. The use having the highest weight is selected to be served the next scheduled transmission in the given timeslot.
摘要:
A system for managing data transmission from a number of queues (12-1,...12-N) employs a regular credit count and a history credit count for each queue. Generally, the regular credit count is used in arbitration (22). The count is decreased when data is transmitted from the queue and increased at given intervals if the queue is facing no transmission-blocking backpressure. The history credit count is increased in lieu of the regular credit count when transmission from the queue is blocked. Thus, the history credit count keeps track of potential transmission opportunities that would be lost due to the blocking of transmission from the queue. The history credit counts are periodically polled instead of the regular credit counts to give each queue an opportunity to catch up in its use of transmission opportunities.
摘要:
A method and apparatus for allocating and using a finite resource to transmit wireless information signals to a plurality of subscriber units is disclosed. Individual subscriber units transmit data rate requests to serving base stations. The data rate requests and weight values associated with each subscriber unit are compared (758) in order to select a subscriber unit as the recipient of data transmitted through the finite resource at any given time. To maximize throughput without starving any single subscriber unit, the method includes calculation and comparison of a desirability metric (766) in choosing a subscriber unit from among a subset of the plurality of subscriber units having comparable weight values.