An adaptive congestion control device (600) and method minimize congestion using independent congestion level indicators. The invention allows efficient recovery for an integrated packet network that becomes congested and allows a user to utilize the network on a space-available basis when capacity is available.
An ATM switch capable of preventing the network resource from being wasted during the occurrence of an overcrowding condition. In the ATM switch, both a message type and a processing mode are stored in correspondence to the connections. When the discarding of a cell occurs, the connection to which the discarded cell belongs is set to a discard mode by a cell discard controlling circuit, and each cell constituting the same message as that of the discarded cell out of the subsequent cells is discarded, and when a demarkation of the message has been detected, the processing mode is returned to a transfer mode, whereby the subsequent received cells are transferred in a normal manner. Thus, the cell which has become useless for a reception terminal is discarded in the network.
A scalable method for efficient dynamic allocation of buffer resources in a store-and-forward device, such that high utilization can be maintained with small average buffer occupancy by providing asymmetric congestion control with opportune random detection. Also provided is tolerance of transient onset of congestion and fairness toward bursty traffic with ready reaction to declines in congestion.
A traffic management policing device (TMPD) (600) and method (TMPM) (700) monitor and substantially enforce a sustainable cell rate (SCR) and burst tolerance (BT) in a cell relay network utilizing a second-order leaky bucket system in conjunction with a peak cell rate (PCR) leaky bucket, thus substantially providing a predetermined quality of service.
A linecard codec (250) permitting an increased throughput connection between a subscriber modem (20) and a service provider coupled to a digital backplane (150). The linecard codec (250) includes an analog interface (152) to the Public Switched Telephone Network, a digital interface (119) to the digital backplane (150), conversion circuits (258, 280) interspersed between the analog interface (152) and the digital interface (119), and a controller (340) having a network interface (350) and configured to format requests for bandwidth and transmit them to a network administrator of the digital backplane (150). A code recognition mechanism (272) is used to monitor the Pulse Code Modulated (PCM) signals from service providers and in combination with control logic (300) and the controller (340) provides a way to allocate and deallocate timeslots on the digital backplane (150).
A priority scheme is based on an amount of preallocated bandwidth unused by channel unit ports. A first water level in a first bucket is associated with an amount of allotted bandwidth unused by the channel unit and a second water level in a second bucket is associated with an amount of unused allotted bandwidth exceeding an overflow level of the first bucket. A priority value is derived from the first water level when the first water level is above zero. The priority value is derived from the second water level when the first water level is below or equal to zero. In another aspect of the invention, the high priority value is determined by tracking a percentage utilization of allocated bandwidth for a predetermined number of time increments comprising a measurement time period.
