Patent · US Expired

Fiber channel flow control method and apparatus for interface to metro area transport link

US6765871B1 · kind B1 · utility

36Cited by
6References
16Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 29, 2000
Grant dateJul 20, 2004
Priority date
Expiry dateNov 25, 2022

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04L47/39
  • WIPO fieldDigital communication
  • WIPO sectorElectrical engineering

Abstract

This invention relates to a method and apparatus for controlling the flow of fiber channel (FC) data frames from a fiber channel link to a metropolitan area link of lesser bandwidth (a synchronous optical network (SONET)). The release of each data unit by a data source for transport onto the first channel is governed by a credit-based protocol whereby one data unit is released upon the provision of one credit unit. A first marker identifies a high limit H of the buffer at which a first condition occurs, H being less than N and the first condition applying when the number of data units in the buffer is greater than H. A second marker identifies a low limit L of the buffer at which a second condition occurs, L being less than H and the second condition applying when the number of data units in the buffer is less than L. A credit unit owed counter O counts the number of credit units which become owed to the data source when the second condition applies. A third marker Max identifies a maximum number of credit units that may be provided to the data source when the first condition applies and the value of the credit unit counter is greater than zero. Through this invention, effective me…

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