Patent · US Expired

Backpressure mechanism for switching fabric

US7426185B1 · kind B1 · utility

40Cited by
30References
58Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 5, 2003
Grant dateSep 16, 2008
Priority date
Expiry dateNov 27, 2025

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04L49/3072
  • WIPO fieldDigital communication
  • WIPO sectorElectrical engineering

Abstract

Roughly described, a packet switching fabric contains a separate queue scheduler for each combination of an input module and a fabric output port. The schedulers may also be specific to a single class of service. Each queue scheduler schedules its packets without regard to state of other input queues and without regard to packets destined for other output ports. In an aspect, the fabric manages per-flow bandwidth utilization of output port bandwidth capacity by monitoring the same and asserting backpressure toward the queue scheduler for any thread that is exceeding its bandwidth allocation. In another aspect, a switching fabric uses leaky buckets to apply backpressure in response to overutilization of downstream port capacity by particular subflows. In another aspect, a switching fabric includes a cascaded backpressure scheme.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.