Patent · US Expired

Sonet H4 byte generator

US5001708A · kind A · utility

16Cited by
2References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 12, 1989
Grant dateMar 19, 1991
Priority date
Expiry dateMay 12, 2009

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S370/907
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

An H4 byte generating algorithm is implemented by circuitry which includes counters for generating the H4 byte. The circuit is provisioned to indicate whether it is operating in a terminal multiplexer mode or an add-drop multiplexer mode. In the terminal multiplexer mode the counters are allowed to free run and continually produce successive H4 byte outputs. In the add-drop multiplexer mode selected counter outputs are compared with the received H4 byte and the number of mismatches is accumulated by a mismatch counter. When the mismatch counter reaches a predetermined number the value of the received H4 byte is loaded into the H4 byte counters and the mismatch counter is reset. Each time a proper match between H4 counter outputs and the received H4 byte is sensed, the mismatch counter is reset to 0. The presence of a red alarm will also result in the resetting of the mismatch counter and free running of the H4 byte counters.

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