公开(公告)号：US20250096891A1

公开(公告)日：2025-03-20

申请号：US18466901

申请日：2023-09-14

Applicant: Cisco Technology, Inc.

Inventor： Alberto Arnaldo Tanzi ,  Giovanni Osnago ,  Maurizio Gazzola

IPC: H04B10/079

Abstract: An optical network element detects an input optical signal at a preamplifier input and sets an output power level of the preamplifier at a predetermined Automatic Power Reduction (APR) power level. The optical network element starts an APR timer that expires after a first predetermined time period. While the APR timer is running, the optical network element measures an input power level of the input optical signal and calculates a span loss as a function of the difference between the predetermined APR power level and the measured input power level. After the expiration of the APR timer, the optical network element adjusts the output power level of the preamplifier output based on the calculated span loss.

公开(公告)号：US20210211786A1

公开(公告)日：2021-07-08

申请号：US17202984

申请日：2021-03-16

Applicant: Cisco Technology, Inc.

Inventor： Gilberto Loprieno ,  Luca Della Chiesa ,  Stefano Binetti ,  Stefano Piciaccia ,  Giovanni Osnago

IPC: H04Q11/00

Abstract: A method of obtaining a measure of asymmetry between optical fibers of a forward and reverse paths is provided in order to synchronize clocks of optical nodes connected by asymmetrical optical fiber paths. The method includes receiving, at first and second arrival times, from a first optical network device, a first optical signal transmitted on a first optical fiber and a second optical signal transmitted on a second optical fiber, calculating a first time difference between the second arrival time and the first arrival time. The method includes determining a measure of asymmetry between the first optical fiber and the second optical fiber based on the first time difference and a second time difference between a first time of transmission by the first optical network device of the first optical signal and a second time of transmission by the first optical network device of the second optical signal.

公开(公告)号：US11483635B2

公开(公告)日：2022-10-25

申请号：US17202984

申请日：2021-03-16

Applicant: Cisco Technology, Inc.

Inventor： Gilberto Loprieno ,  Luca Della Chiesa ,  Stefano Binetti ,  Stefano Piciaccia ,  Giovanni Osnago

IPC: H04Q11/00 ,  H04B10/079 ,  H04B10/071 ,  H04L7/00

Abstract: A method of obtaining a measure of asymmetry between optical fibers of a forward and reverse paths is provided in order to synchronize clocks of optical nodes connected by asymmetrical optical fiber paths. The method includes receiving, at first and second arrival times, from a first optical network device, a first optical signal transmitted on a first optical fiber and a second optical signal transmitted on a second optical fiber, calculating a first time difference between the second arrival time and the first arrival time. The method includes determining a measure of asymmetry between the first optical fiber and the second optical fiber based on the first time difference and a second time difference between a first time of transmission by the first optical network device of the first optical signal and a second time of transmission by the first optical network device of the second optical signal.

公开(公告)号：US10986426B1

公开(公告)日：2021-04-20

申请号：US16732836

申请日：2020-01-02

Applicant: Cisco Technology, Inc.

Inventor： Gilberto Loprieno ,  Luca Della Chiesa ,  Stefano Binetti ,  Stefano Piciaccia ,  Giovanni Osnago

IPC: H04Q11/00 ,  H04B10/079 ,  H04B10/071 ,  H04L7/00

Abstract: A method of obtaining a measure of asymmetry between optical fibers of a forward and reverse paths is provided in order to synchronize clocks of optical nodes connected by asymmetrical optical fiber paths. The method includes receiving, at first and second arrival times, from a first optical network device, a first optical signal transmitted on a first optical fiber and a second optical signal transmitted on a second optical fiber, calculating a first time difference between the second arrival time and the first arrival time. The method includes determining a measure of asymmetry between the first optical fiber and the second optical fiber based on the first time difference and a second time difference between a first time of transmission by the first optical network device of the first optical signal and a second time of transmission by the first optical network device of the second optical signal.