This invention relates to telecommunications systems and more particularly to detection and resolution of cabling errors in optical networks.
Detection of fiber cabling connectivity changes is very difficult within a meshed optical network for service providers offering switched lambda services. Optical switching equipment and their network management systems (NMS) presently do not support automatic detection and display of fiber connectivity changes within meshed optical networks, therefore detection of cabling-error related outages is manual, inconsistent and unreliable.
Automatic and reliable detection of fiber connectivity errors between nodes within optical networks is extremely important in reducing the length of network outages, especially since it is generally agreed by service providers that the majority of optical network outages (often as high as 70%) are not due to external heavy equipment activity (such as road-work), but in fact due to cabling errors by their own technicians at fiber patch panels. These cabling errors include, but are not limited to the wrong cable being unplugged, fibers being plugged into the wrong jack, or fibers plugged into the wrong patch panel.
In view of the complex nature of lightpath architecture and cross-connects, It is often difficult and time consuming to detect when a cabling change has been made in existing meshed optical networks since neither the optical networking equipment or the corresponding NMS can automatically detect a fiber connectivity change between nodes, and distinguish it from a fiber outage.
Existing NMS systems and optical networking equipment typically rely on a manual definition of optical links to define the intended cabling or fiber connectivity between nodes in the network, then rely on external fiber inventory and mapping software packages to document installed fiber connectivity within the network. Determination of fiber cabling errors, then is a manual cross-referencing task for the operator once node hardware or software faults have been ruled out. Essentially once all other root causes have been eliminated then cabling faults become suspect.
The shortcomings of existing solutions are:
In the example shown in
In the fiber cabling change shown in
This invention proposes a method to automatically detect and direct operator resolution of fiber cabling errors.
The problem solved by the present invention is that optical equipment and/or their NMS cannot automatically detect fiber connectivity changes and cabling errors within an optical network. The invention provides automatic fiber link detection, automatic detection of fiber cabling connectivity changes, updated data to display fiber cabling changes or errors graphically, and also provides data to direct operator resolution of the cabling changes or errors.
Therefore, in accordance with a particular aspect of the present invention there is provided a method of automatically detecting fiber cabling errors in an optical network comprising: detecting initial fiber connectivity between optical nodes in the network; storing information regarding the initial fiber link connectivity; detecting any cabling changes; and determining the impact of the cabling changes on service through the network.
In accordance with a further aspect of the invention there is provided a system for automatically detecting fiber cabling errors in an optical network comprising an automatic optical link detection module to detect connectivity between optical nodes in the optical network; an automatic cabling change detection module for storing initial fiber link connectivity and detecting any cabling changes; and a cabling change impact and resolution module for determining impact of any cabling change.
The invention will now be described in greater detail with, reference to the attached drawings wherein:
The invention, as will now be described in greater detail provides apparatus and methods of automatically detecting cable routing in a mesh optical network. The apparatus, involving dedicated software allows an operator to view, graphically connections as they exist prior to any changes being made. Typically the operator is provided with a graphical user interface such as a lap top computer which allows the operator to connect to the NMS and download and control connection activity. In one embodiment the connection data is stored in memory at the NMS while it is to be understood that certain data can be stored at network elements.
According to the invention, an operator or technician is shown the impact of any changes being made and given an opportunity to accept or reject the changes if the changes might have negative affects on the network. The operator is prompted, through the GUI to accept all changes before they are implemented
The invention utilizes a three part solution including:
Implementation of the invention can vary including any of the following:
Regardless of where the three software components of this invention are implemented (node software, or management system software), the end result is that operators will have a solution that allows automatic detection of new optical network connectivity, automatic detection of optical cabling changes between optical network equipment, automatic service impact determination, and directed operator resolution of fiber cabling changes or errors.
This invention offers the following unique functionality:
Fiber cabling or connectivity changes can be intentional or the result of cabling errors by technical personnel. Operator errors resulting in a wrong fiber being deleted will be almost eliminated using this invention, since operators can be forced to execute a multi-step process to accept new cabling and delete original fibers. The invention provides information for the operator to identify all services impacted resulting from acceptance of the new fiber connectivity, and supports directed operator resolution implementations. Directed operator resolution force the operator to acknowledge and disconnect all the affected services first, before the original fiber link can be deleted from the network map on the NMS.
A multi-step cabling change/error resolution process as supported by this invention significantly reduces the chance of unintentional or erroneous deletion of a wrong fiber from a management system, and ensures that the complete operational impact of the cabling change is clear to the operator before accepting the change.
The invention utilizes software written to implement the following three functional modules:
Implementation of the invention can be a consolidated implementation combining all three modules (AOLD, ACCD, and CCIR) within an EMS, NMS, or OSS system, consolidated within optical network node software, or the three-part solution can be distributed across optical network equipment software and management software.
The Automatic Optical Link Detection (AOLD) module can be written as a component of the optical equipment's node software as in the following example implementation, or could be implemented in software within an EMS, NMS or OSS system or sub-component. Ultimately the output of the AOLD module would typically be made available to an application, and GUI on an EMS, NMS, third party software package, or OSS system.
The Automatic Cabling Change Detection (ACCD) module can be written as a component of centralized NMS software, as in the following example implementation, or could be implemented in software within optical equipment or node software, EMS, or OSS system or sub-component. Ultimately the output of the ACCD module would typically be made available to an application and GUI on an EMS, NMS, third party software package, or OSS system.
The Cabling Change Impact and Resolution (CCIR) module can be written as a component of centralized NMS software, as in the following example implementation, or could be implemented in software within optical equipment or node software, EMS, or OSS system or subcomponent. Ultimately the output of the ACCD module would typically be made available to an application and GUI on an EMS, NMS, third party software package, or OSS system.
The following example is intended to show one potential implementation of the invention. As previously explained other implementations of this invention are possible. The example implementation as outlined in
This implementation of an ‘Automatic Optical Link Detection (AOLD)’ module uses a Link Management Protocol (LMP) to automatically detect initial optical link connectivity, as well as automatically detecting new optical link connectivity resulting from cabling moves or miscabling. In this case the LMP software is implemented as part of the optical equipment (or node) software.
This implementation of an ‘Automatic Cabling Change Detection (ACCD)’ module (as shown in
This implementation of a ‘Cabling Change Impact and Resolution (CCIR)’ module is a centralized NMS-based module which automatically determines service impact of cabling changes, supplies data to visualize cross-connect and lightpath impacts on the NMS graphical user interface (GUI), and supplies data to direct operator resolution of cabling problems via the NMS GUI.
In this implementation, the invention supports a representation of both the original fiber connectivity between nodes and the newly detected fiber connectivity between nodes. Referring to the fiber change example shown in
Since the AOLD and ACCD modules provide complete status information on both the original optical connectivity and the newly discovered optical connectivity, the corresponding EMS, NMS, or OSS can graphically display the information provided. The system(s) providing graphical representation of the fiber connectivity could then for example, be updated by both the AOLD and ACCD modules to graphically display the original fiber link as down, and the new fiber could be displayed as suspect until the original cable is deleted or restored (depending on whether the cabling change was intentional or accidental).
In this implementation, the CCIR module provides automatic impact analysis data, and supports operator directed resolution of the cable change or miscabling situation. The operator utilizes ‘Resolve Miscabling’ functionality offered via a GUI window in the NMS. The CCIR clearly identifies which services are impacted through acceptance of the new fiber connectivity, and forces the operator to disconnect all the affected services first, before the original fiber link can be deleted. The NMS GUI enforces a multi-step operator process, which significantly reduces the chance of unintentional or erroneous deletion of a wrong fiber by an operator, and ensures that the complete operational impact of the cabling change is clear to the operator before executing or accepting the change in cabling.
In this implementation, the node software in the optical network nodes utilizes a point-to-point Link Management Protocol, which automatically detects lambda-level connectivity between adjacent optical network nodes.
To automatically detect new lambda-level connectivity between nodes:
To automatically detect changes in lambda-level connectivity between nodes for all connected or unconnected lambdas:
Therefore to support the example identified in
The NMS software part of the invention in this implementation performs the following functions:
The ‘resolve cabling change’ utility offered as part of this example implementation utilizes NMS windows as shown in
The ‘resolve cabling change’ utility in this example implementation is accessed after selecting a suspect fiber from a fiber list or through direct point-and-click selection from a network map on the NMS. The first NMS window shown in
The second ‘resolve cabling change’ window shown in
The third ‘resolve cabling change’ window of this example implementation, as shown in
To accept the cabling from A-D in this implementation (as shown in
By the time the operator has acknowledged each of the listed impacts it should be very clear what the overall impact will be of the cabling change. By having to actively step through and acknowledge impact within each of the windows documented in
If the cable change is accepted, then all the acknowledged fibers will be automatically deleted, the acknowledged cross-connects will be automatically disconnected, and the acknowledged lightpaths will be automatically disconnected when the operator hits the final ‘finish’ button as shown in
If during the process of resolving the miscabling the operator realizes that this new connectivity is not correct and that the original fiber should not be deleted, (as determined by understanding the impact on fibers, cross-connects, and lightpaths,), the operation to accept the new fiber can be easily aborted through a cancel button offered in this implementation.
By the time the operator has acknowledged all of the listed impacts it should be very clear as to the overall impact of the cabling change. By having to actively step through and acknowledge impact within each of the windows documented in
If the cable change is recognized to be an error, the ‘Resolve Cabling’ operation would be canceled by the operator, technical staff will be dispatched to restore Fiber A-B, and no cross-connects or lightpaths will have been disconnected by the NMS. Fiber A-C and Fiber A-D would then be deleted by the operator, to correct the network representation on the NMS network map. In this example, service disruption will be minimized through proper impact awareness to the operator, and automatic detection of the cabling change in the first place.
Although particular embodiments of the invention have been described and illustrated it will be apparent to one skilled in the art that numerous changes can be made without departing from the basic concept. It is to be understood, however, that such changes will fall within the full scope of the invention as defined by the appended claims.
This application claims the benefit of U.S. Provisional Application No. 60/398,049 filed Jul. 24, 2002.
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/CA03/01111 | 7/23/2003 | WO | 2/16/2006 |
Number | Date | Country | |
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60398049 | Jul 2002 | US |