Reachability determination in wavelength division multiplexing network based upon fiber loss measurements

Patent metadata

Field	Value
Publication number	US-10200121-B2
Application number	US-201715623240-A
Country	US
Kind code	B2
Filing date	Jun 14, 2017
Priority date	Jun 14, 2017
Publication date	Feb 5, 2019
Grant date	Feb 5, 2019

Abstract

Devices, computer-readable media and methods are disclosed for determining reachability for a wavelength connection in a telecommunication network. For example, a processor deployed in a telecommunication network may calculate a fiber loss on a link in the telecommunication network using optical power measurements and determine that a destination node of a wavelength connection is not reachable via a path that includes the link based upon the fiber loss of the link that is calculated. In one example, the determining is based upon a number of links in the path, an effective fiber loss for each link in the path, a penalty for nodes in the path, and an acceptable loss value. The processor may further perform a remedial action in response to determining that the destination node of the wavelength connection is not reachable via the path.

First claim

What is claimed is:

1. A method comprising:
calculating, by a processor deployed in a telecommunication network using optical power measurements, a fiber loss on a link in the telecommunication network;
determining, by the processor, that a destination node of a wavelength connection is not reachable via a path that includes the link based upon the fiber loss of the link that is calculated, wherein the determining is based upon:
a number of links in the path;
an effective fiber loss for each link in the path;
a penalty for nodes in the path; and
an acceptable loss value; and

performing, by the processor, a remedial action in response to determining that the destination node of the wavelength connection is not reachable via the path.

2. The method of claim 1 , wherein the determining that the destination node of the wavelength connection is not reachable is based upon:

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h

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where n is the number of links in the path, l i is the effective fiber loss for each link i, h is the penalty for nodes in the path, and R is the acceptable loss value.

3. The method of claim 1 , wherein the determining that the destination node of the wavelength connection is not reachable is based upon:

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AMP

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ROADM

≤

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where n is the number of links in the path, l i is the effective fiber loss for each link i, m is a number of amplifiers in the path, h AMP is a loss for optical amplifiers in the path, h ROADM is a loss for reconfigurable optical add-drop multiplexers in the path, and R is the acceptable loss value.

4. The method of claim 1 , wherein the effective fiber loss for each link is specific to a wavelength of the wavelength connection.

5. The method of claim 1 , wherein the acceptable loss value is based on an end of life acceptable loss for a single link and a margin.

6. The method of claim 1 , further comprising:
adjusting the acceptable loss value based upon a variability in a plurality of calculations of the fiber loss on the link.

7. The method of claim 1 , wherein the remedial action comprises:
adding a regenerator to the path; and
establishing the wavelength connection via the path.

8. The method of claim 1 , wherein the remedial action comprises:
reducing a bitrate for the wavelength connection as compared to a requested bitrate contained in a request to establish the wavelength connection; and
establishing the wavelength connection via the path.

9. The method of claim 1 , wherein the remedial action comprises:
selecting a different path for the wavelength connection.

10. The method of claim 1 , further comprising:
receiving a request to establish the wavelength connection in the telecommunication network; and
selecting the path through the telecommunication network for the wavelength connection based upon a set of initial criteria.

11. The method of claim 10 , wherein the path is selected by applying the set of initial criteria to a shortest path first algorithm, wherein the set of initial criteria includes information for:
a topology of the telecommunication network; and
available wavelength resources on links in the telecommunication network.

12. The method of claim 10 , wherein the request to establish the wavelength connection comprises a request for a persistent connection.

13. The method of claim 12 , further comprising:
receiving an additional request to establish an additional wavelength connection in the telecommunication network comprising a non-persistent connection;
determining that a destinati

Assignees

• At & T Ip I Lp

Inventors

• Woodward Sheryl
• Tse Kathleen
• Birk Martin
• Chiu Angela
• Bathula Balagangadhar

Classifications

• H04Q11/00

  Selecting arrangements for multiplex systems (multiplex systems H04J) · CPC title

• H04Q11/0066

  Provisions for optical burst or packet networks · CPC title

• H04B10/071

  using a reflected signal, e.g. using optical time domain reflectometers [OTDR] · CPC title

• H04B10/07953 Primary

  Monitoring or measuring OSNR, BER or Q · CPC title

• H04B10/07957

  Monitoring or measuring wavelength · CPC title