Patent · US Expired

Systems and methods for implementing ABR with guaranteed MCR

US6657959B1 · kind B1 · utility

11Cited by
97References
13Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 17, 1999
Grant dateDec 2, 2003
Priority date
Expiry dateJun 17, 2019

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04L2012/5679
  • WIPO fieldDigital communication
  • WIPO sectorElectrical engineering

Abstract

Systems and methods for maintaining cell transmissions at or above the minimum cell transfer rate for ABR-category VCs. An ABR schedule table (AST) in a memory stores ABR VCs scheduled for transmissions. A pointer to the AST indicates that the ABR VC currently addresses is ready to transmit a cell. The schedule pointer is incremented every cell transmission time. When a cell of a particular VC is sent, the VC is rescheduled in another time slot in the AST such that the next cell for that VC is transmitted at close to or equal to that VC's allowed cell transfer rate (ACR) while maintaining its minimum cell transfer rate (MCR). To determine the next time slot in which to reschedule the VC, the system uses an ACR bitmap that compresses the AST and which identifies entries that are not occupied by a VC scheduled for a transmission. The system determines the time slot in the AST that would allow the VC to be transmitted at its ACR. The system then checks the ACR bitmap to determine whether that ACR slot is unoccupied. If occupied, the system searches the ACR bitmap to locate the next empty slot in the AST. If all slots between the ACR slot and the slot which provides for an MCR transmis…

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