METHOD OF IDENTIFYING LONG-SHINING ROGUE ONU IN PASSIVE OPTICAL NETWORK

• US 20160269811A1
• Filed: 10/31/2014
• Published: 09/15/2016
• Est. Priority Date: 11/21/2013
• Status: Active Grant

• Current Assignee: Alcatel-Lucent SA (Nokia Corporation)
• Original Assignee: Alcatel-Lucent SA (Nokia Corporation)
• Inventors: CHANG, Qingjiang
• Granted Patent: US 10,165,341 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H04J 14/0239 in WDM-PON sharing multiple downstream wavelengths for groups of optical network units [ONU], e.g. multicasting wavelengths
• CPC Class Codes: H04J 14/08 Time-division multiplex systems
• CPC Class Codes: H04J 2203/0062 Testing
• CPC Class Codes: H04Q 11/0067 Provisions for optical access or distribution networks, e.g. Gigabit Ethernet Passive Optical Network (GE-PON), ATM-based Passive Optical Network (A-PON), PON-Ring
• CPC Class Codes: H04Q 2011/0079 Operation or maintenance aspects
• CPC Class Codes: H04Q 2011/0083 Testing; Monitoring
• CPC Class Codes: H04Q 2011/0096 Tree

Abstract

The invention discloses a method, in an OLT in a passive optical network, of identifying a long-shining rogue ONU, the method comprising the steps of: A. allocating a specific radio frequency signal at a different frequency to each of ONUs in the passive optical network; and B. when the long-shining rogue ONU is detected in the passive optical network: b1. broadcasting a control message to each of the ONUs; b2. receiving uplink signals in the uplink; b3. recovering the specific radio frequency signals transmitted by the normal ONUs from the uplink signals; and b4. identifying an absent specific radio frequency signal according to the recovered specific radio frequency signals, wherein the ONU corresponding to the absent specific radio frequency signal is the long-shining rogue ONU. The invention further discloses an OLT device performing the method and a method, in an ONU, of assisting the OLT in identifying a long-shining rogue ONU.

Claims

1. A method, in an OLT in a passive optical network, of identifying a long-shining rogue ONU, the method comprising the steps of:

A. allocating a specific radio frequency signal at a different frequency to each of ONUs in the passive optical network; and

B. when the long-shining rogue ONU is detected in the passive optical network, which transmits noise or a random signal so that uplink signals of normal ONUs can not be received normally;

b1. broadcasting a control message to each of the ONUs, wherein the control message instructs each of the ONUs to transmit the specific radio frequency signal in the uplink;

b2. receiving uplink signals in the uplink;

b3. recovering the specific radio frequency signals transmitted by the normal ONUs from the uplink signals; and

b4. identifying an absent specific radio frequency signal according to the recovered specific radio frequency signals, wherein an ONU corresponding to the absent specific radio frequency signal is the long-shining rogue ONU.

2. The method according to claim 1, wherein the step b3 particularly comprises:

performing Fourier transformation on the received uplink signals to thereby recover the specific radio frequency signals transmitted by the normal ONUs from the uplink signals.

3. The method according to claim 2, wherein the uplink signals include the noise or the random signal transmitted by the long-shining rogue ONU and the specific radio frequency signals transmitted by the normal ONUS.

4. The method according to claim 1, wherein the specific radio frequency signals are low-frequency signals.

5. The method according to claim 4, wherein the specific radio frequency signals can be encoded and inserted into an uplink data frame.

6. A method, in an ONU in a passive optical network, of assisting an OLT in identifying a long-shining rogue ONU, the method comprising the steps of:

providing the ONU with a specific radio frequency signal, wherein frequency of a specific radio frequency signal of each of ONUs in the passive optical network is different from one another; and

when a control message broadcasted by the OLT to instruct each of the ONUs to transmit the specific radio frequency signal in the uplink is received;

temporarily stopping an uplink data signal from being transmitted to the OLT in the uplink; and

transmitting the specific radio frequency signal to the OLT in the uplink.

7. The method according to claim 6, wherein the specific radio frequency signal is a low-frequency signal.

8. The method according to claim 6, wherein the method further comprises the steps of:

encoding the specific radio frequency signal and inserting the encoded specific radio frequency signal into an uplink data frame for transmission to the OLT.

9. An OLT apparatus for identifying a long-shining rogue ONU in a passive optical network, the OLT apparatus comprising:

a transmitting module configured to transmit downlink signals to ONUs in the passive optical network;

a receiving module configured to receive uplink signals from the ONUs in the passive optical network;

a decoding module configured to recover specific radio frequency signals transmitted by normal ONUs from the uplink signals, wherein frequency of the specific radio frequency signal of each of the ONUs in the passive optical network is different from one another; and

a processing module configured to identify an absent specific radio frequency signal according to the specific radio frequency signals recovered by the decoding module, wherein an ONU corresponding to the absent specific radio frequency signal is the long-shining rogue ONU.

10. The OLT apparatus according to claim 9, wherein:

when the long-shining rogue ONU is detected in the passive optical network, which transmits noise or a random signal so that the uplink signals of the normal ONUs can not be received normally;

the transmitting modules broadcasts a control message to each of the ONUs, wherein the control message instructs each of the ONUs to transmit the specific radio frequency signal in the uplink;

the receiving module receives the uplink signals in the uplink, wherein the uplink signals include the noise or the random signal transmitted by the long-shining rogue ONU and the specific radio frequency signals transmitted by the normal ONUs;

the decoding module recovers the specific radio frequency signals transmitted by the normal ONUs from the uplink signals; and

the processing module identifies the absent specific radio frequency signal according to the specific radio frequency signals recovered by the decoding module, wherein the ONU corresponding to the absent specific radio frequency signal is the long-shining rogue ONU.

11. The OLT apparatus according to claim 10, wherein the decoding module performs Fourier transformation on the received uplink signals to thereby recover the specific radio frequency signals transmitted by the normal ONUs from the uplink signals.

12. The OLT apparatus according to claim 9, wherein the specific radio frequency signals are low-frequency signals.

13. The OLT apparatus according to claim 12, wherein the specific radio frequency signals can be encoded and inserted into an uplink data frame.