CROSS REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Patent Application Serial Number 63/338,834 filed May 5, 2023.

BACKGROUND

[0002] The subject matter of this application relates to passive optical networks.

[0003] A passive optical network (PON) is often employed as an access network, or a portion of a larger communication network. The communication network typically has a high-capacity core portion where data or other information associated with telephone calls, digital television, and Internet communications is carried substantial distances. The core portion may have the capability to interact with other networks to complete the transmission of telephone calls, digital television, and Internet communications. In this manner, the core portion in combination with the passive optical network enables communications to and communications from subscribers (or otherwise devices associated with a subscriber, customer, business, or otherwise).

[0004] The access network of the communication network extends from the core portion of the network to individual subscribers, such as those associated with a particular residence location (e.g., business location). The access network may be wireless access, such as a cellular network, or a fixed access, such as a passive optical network or a cable network.

[0005] Referring to FIG. 1, in a PON 100, a set of optical fibers and passive interconnecting devices are used for most or all of the communications through the extent of the access network. A set of one or more optical network terminals (ONTs) 110 are devices that are typically positioned at a subscriber’s residence location (e.g., or business location). The term “ONT” includes what is also referred to as an optical network unit (ONU). There may be any number of ONTs associated with a single optical splitter 120. By way of example, 32 or 64 ONTs are often associated with the single network optical splitter 120. The optical splitter 120 is interconnected with the respective ONTs 110 by a respective optical fiber 130, or otherwise a respective fiber within an optical fiber cable. Selected ONTs may be removed and/or added to the access network associated with the optical splitter 120, as desired. There may be multiple optical splitters 120 that are arranged in a cascaded arrangement.

[0006] The optical fibers 130 interconnecting the optical splitter 120 and the ONTs 110 act as access (or “drop”) fibers. The optical splitter 120 is typically located in a street cabinet or other structure where one or more optical splitters 120 are located, each of which are serving their respective set of ONTs. In some cases, an ONT may service a plurality of subscribers, such as those within a multiple dwelling unit (e.g., apartment building). In this manner, the PON may be considered a point to multipoint topology in which a single optical fiber serves multiple endpoints by using passive fiber optic splitters to divide the fiber bandwidth among the endpoints.

[0007] An optical line terminal (OLT) 140 is located at the central office where it interfaces directly or indirectly with a core network 150. An interface 160 between the OLT 140 and the core network 150 may be one or more optical fibers, or any other type of communication medium. The OLT 140 forms optical signals for transmission downstream to the ONTs 110 through a feeder optical fiber 170, and receives optical signals from the ONTs 110 through the feeder optical fiber 170. The optical splitter 120 is typically a passive device that distributes the signal received from the OLT 140 to the ONTs 110. Similarly, the optical splitter 120 receives optical signals from the ONTs 110 and provides the optical signals though the feeder optical fiber 170 to the OLT 140. In this manner, the PON includes an OLT with a plurality of ONTs, which reduces the amount of fiber necessary as compared with a point-to-point architecture. [0008] As it may be observed, an optical signal is provided to the feeder fiber 170 that includes all of the data for the ONTs 110. Accordingly, all the data being provided to each of the ONTs is provided to all the ONTs through the optical splitter 120. Each of the ONTs selects the portions of the received optical signals that are intended for that particular ONT and passes the data along to the subscriber, while discarding the remaining data. Typically, the data to the ONTs are time division multiplexed to the feeder fiber 170, and similarly time division multiplexed to each of the ONTs.

[0009] Upstream transmissions from the ONTs 110 through the respective optical fibers 130 are typically transmitted in bursts according to a schedule provided to each ONT by the OLT. In this way, each of the ONTs 110 will transmit upstream optical data at different times. In some embodiments, the upstream and downstream transmissions are transmitted using different wavelengths of light so that they do not interfere with one another. In this manner, the PON may take advantage of wavelength-division multiplexing, using one wavelength for downstream traffic and another wavelength for upstream traffic on a single mode fiber.

[0010] The schedule from the OLT allocates upstream bandwidth to the ONTs. Since the optical distribution network is shared, the ONT upstream transmission would likely collide if they were transmitted at random times. The ONTs typically lie at varying distances from the OLT and/or the optical splitter, resulting in a different transmission delay from each ONT. The OLT measures the delay and sets a register in each ONT to equalize its delay with respect to the other ONTs associated with the OLT. Once the delays have been accounted for, the OLT transmits so-called grants in the form of grant maps to the individual ONTs. A grant map is a permission to use a defined interval of time for upstream transmission. The grant map is periodically dynamically recalculated, such as for each upstream frame. The grant map allocates bandwidth to all the ONTs, such that each ONT receives timely bandwidth allocation for its service needs. Much of the data traffic, such as browsing websites, tends to have bursts and tends to be highly variable over time. By way of a dynamic bandwidth allocation (DBA) among the different ONTs, a PON can be oversubscribed for upstream traffic.

BRIEF DESCRIPTION OF THE DRAWINGS

[0011] For a better understanding of the invention, and to show how the same may be carried into effect, reference will now be made, by way of example, to the accompanying drawings, in which:

[0012] FIG. 1 illustrates a network that includes a passive optical network.

[0013] FIG. 2 illustrates a PON network design process.

[0014] FIG. 3 illustrates a design tool for a PON network together with additional data.

[0015] FIG. 4 illustrates a job queue for the design tool.

[0016] FIG. 5 illustrates automatic updating of the design tool based upon the job queue.

DETAILED DESCRIPTION

[0017] As the service provider is building out the access network, the OLT, the ONTs, the fibers, the splitters, and other components of the access network are installed to provide services to particular residences. In order to install a PON network, the service provider needs to obtain a right of way to install each portion of the PON network, such as a node or otherwise the fiber optical cable, which crosses and/or uses public property and/or private property. In addition to obtaining the right of way for each portion of the PON network, the service provider often needs to obtain suitable permits from various government agencies, such as local, state, and/or federal. [0018] By way of example, the fiber optic cable may be suspended from a series of telephone poles. In the case of telephone poles, the service provider may need to obtain the right of way and/or permission from the owner of the telephone poles to attach the fiber optical cable to the poles. Also, a determination may need to be made if each of the telephone poles has remaining capacity to install an additional fiber optic cable, or otherwise. By way of example, the fiber optic cable may be routed underground through some type of conduit. In the case of routing the fiber optic cable underground, the service provider may need to obtain the right of way and/or permission from the owner of the underground conduit to route the fiber optic cable through the underground conduit. By way of example, a determination may need to be made if each of the conduits has remaining capacity to route an additional fiber optic cable, or otherwise. Also, in some circumstances an existing PON network is upgraded or otherwise modified (e.g., “brownfield”), while in other circumstances a new PON network is installed (e.g., “greenfield”).

[0019] Referring to FIG. 2, the service provider may start with a preliminary design 200 of a PON network to provide service to a set of existing and/or proposed residences. The preliminary design if often optimized to minimize the expense for the installation of the PON network. The preliminary design may include, for example, a set of poles that are to be used, an underground conduit that is to be used, the nodes to that are to be used, the owners of the poles, the owners of the underground conduit, public property to be crossed, and private property to be used together with its owner. The preliminary design 200 may be based upon what is thought to be known about existing network infrastructure, if any, together with information from satellite images of the geographic region of the PON network (e.g., Google Earth). Also, suitable permitting and right of ways may be taken into account in the preliminary design 200.

[0020] Often the assumptions made for the preliminary design 200 are incorrect or otherwise incomplete, so the service provider may drive the network route 210 with a vehicle to geographically map out the PON network. Mapping tools may be used to verify the aspects of the PON network, such as the location of telephone poles, location of roads, and any other obstructions that may exist. In some cases, Lidar may be used as part of the mapping tool. Based upon driving the network route 210, the preliminary design 200 may be modified to provide an improved design 220 that is more aligned with the actual infrastructure. This provides a more accurate representation of the design while incurring limited additional expense. Also, further refined suitable permitting and right of ways may be taken into account in the modified design 220.

[0021] While driving the route provides information for a more detailed representation of the design, it is desirable to further walk the network 230. While walking the network, the service operator may verify each of the aspects of the network. For example, the service provider may obtain an identification number for each telephone pole along with a capacity determination, if necessary, for available additional network capacity. For example, the service provider may audit each of the nodes to determine if additional capacity is available, if desired. For example, the underground conduits may be audited to determine if additional capacity is available, if desired. For example, the service provider may verify the portions of the network that cross or otherwise access public property and/or private property. Also, further refined permitting and right of ways may be taken into account. As a result of walking the network 230 a modified updated design 240 may be determined.

[0022] The detailed design of the PON network may be further refined, as necessary, based upon the available infrastructure and the ability to obtain suitable permitting and right of ways. By way of example, a private property owner may not permit their property to be crossed by a fiber optic cable, therefore requiring the service provider to further modify their network design. By way of example, the local municipality may not provide a permit for aspects of a particular design, therefore requiring the service provider to further modify their network design. [0023] The process of modifying the design continues until a sufficiently high level of confidence is reached that the particular design may be reliably constructed in accordance with applicable permits, right of ways, and capacity.

[0024] Referring to FIG. 3, a physical PON network inventory together with operational characteristics of the PON network may be maintained in a computerized design tool to manage the existing design. As a result of a greenfield deployment in accordance with FIG. 2, the information maintained within the design tool will typically substantially reflect the actual network assets. However, over time as the configuration of the PON network is changed, repairs are made to the network which change aspects of its configuration, additional build out of the network results in changes to the overall configuration, etc., all of which contribute to challenges in maintaining current information in the design tool of the actual network configuration.

[0025] The design tool may track information about the network components, including for example, the physical location, attributes, connectivity, and/or capacity for each aspect of the PON network. This information may be stored in a database so that it may be updated from time to time, where the database may be any manner of storing the information. The design tool may also include network maps of the PON network, with the locations of the network components geographically attributed to different locations on the map of the system. Designers may use the data from the design tool, or the design tool itself, to model the network elements used in the network, including for example, multichannel fiber, nodes, ONTs, OLTs, splitters, etc. The design tool may also maintain the fiber locations together with available physical capacity (e.g., dark fiber) and logical capacity (unused wavelengths or channels). The different information included in the design tool may be in the form of layers, such that layers that are selected are graphically displayed, and those layers that are not selected are not graphically displayed.

[0026] Referring also to FIG. 4, the data from the design tool, or the design tool itself, may be used to provide a job management for detailing designs that are to occur. For example, there may be a queue of jobs 400 to be completed. Based upon the anticipated modifications, the design tool may validate the design, and be used to issue job orders for technicians to complete the modifications to the network. The design tool may track the completion of the job orders 410, and upon completion of job orders, mark that they have been completed.

[0027] After completion of a particular job, in some cases a user of the design tool will review the network design and update the characteristics of the network 420. By updating the characteristics of the network, the historical characteristics of the network may be overwritten or otherwise indicated as historical characteristics of the network. However, periodically the user of the design tool will fail to update the network design resulting in a difference between the network design and the actual network installation. Over time, with additional failures to update the network design, the resulting differences between the network design and the actual network installation will increase.

[0028] Referring to FIG. 5, to alleviate such concerns over whether the design tool has been updated, it is desirable to further include an “auto” update feature for the network design in addition to a queue of job orders. Upon issuance of a particular job order 500, the network design is automatically updated with additional information to reflect the modifications indicated in the particular job order 510. This additional information may be flagged in some manner, such as within the existing data of the network design, or otherwise in a separate layer, of the network design. In this manner, a user of the design tool can observe the changes that are anticipated to be made to the network design for the job order. Preferably, the additional information is flagged in the network design in a manner that indicates that the job has yet to be completed or otherwise verified as being completed. The job order is also added to a queue 520 of job orders.

[0029] After completion of a particular job, the design tool preferably indicates that the particular job is completed 530. Also, after completion of the particular job, the design tool preferably automatically incorporates the updated network design 540. In this manner, the information from the particular job may be incorporated into the network design. The additional information is preferably flagged in some manner different than the auto update network design 510, such as within the existing data of the network design or otherwise in a separate layer, of the network design. In this manner, a user of the design tool can observe the changes that were made to the network design as a result of completing a job. Preferably, the additional information is flagged in the network design in a manner that indicates that the job is completed or otherwise verified as being completed.

[0030] As the network design is updated over time or otherwise updates are completed within the network, it is desirable to further document the modifications in a manner that provides additional information in the future. For example, the particular layout of the components in the network may be of assistance in the verification of the updated design and of assistance to a technician making modifications to the network in the future. To facilitate such information, it is desirable that the technician obtains a digital image or otherwise a three-dimensional scan of the region including the modification (e.g., a node). The digital image or otherwise three-dimensional scan of the region is included within the design tool for future reference. Further, such digital image or otherwise three-dimensional scan is preferably accessible by a link associated with the area in which it is included within the design tool, such as an icon on the tool.

[0031] In some cases, the technicians modifying the network will make additional modifications to the network or otherwise not implement the modifications as indicated in the job order, due to the particular characteristics of the actual network which may not be necessarily reflected in the network design in the design tool. The technician or otherwise a user of the design system may flag that the job order was completed but in a manner that deviates from the particular job order, or otherwise the particular job order may be modified to indicate the modification. In this case, the user of the design tool may obtain additional information from the technician, that is added to the particular job order 550 to include the actual modifications made to the network. This additional information may be used to automatically modify the updated network design for the job and be flagged in some manner together with the original job information, such as within the existing data of the network design, or otherwise in a separate layer, of the network design. In this manner, a user of the design tool can observe the changes that were made to the network design and whether those modifications were based upon the original job order or a modified job order by the technician.

[0032] The characteristics of the network design are preferably not modified until a user of the design tool incorporates the flagged modifications into the network design. In this manner, previous information is not inadvertently lost, while permitting the user to incorporate the desired additional modifications. After the user incorporates the changes into the design tool, the flagged data as a result of the particular job order may be removed or otherwise indicated as incorporated into the network design.

[0033] Moreover, each functional block or various features in each of the aforementioned embodiments may be implemented or executed by a circuitry, which is typically an integrated circuit or a plurality of integrated circuits. The circuitry designed to execute the functions described in the present specification may comprise a general- purpose processor, a digital signal processor (DSP), an application specific or general application integrated circuit (ASIC), a field programmable gate array (FPGA), or other programmable logic devices, discrete gates or transistor logic, or a discrete hardware component, or a combination thereof. The general-purpose processor may be a microprocessor, or alternatively, the processor may be a conventional processor, a controller, a microcontroller or a state machine. The general-purpose processor or each circuit described above may be configured by a digital circuit or may be configured by an analogue circuit. Further, when a technology of making into an integrated circuit superseding integrated circuits at the present time appears due to advancement of a semiconductor technology, the integrated circuit by this technology is also able to be used. [0034] It will be appreciated that the invention is not restricted to the particular embodiment that has been described, and that variations may be made therein without departing from the scope of the invention as defined in the appended claims, as interpreted in accordance with principles of prevailing law, including the doctrine of equivalents or any other principle that enlarges the enforceable scope of a claim beyond its literal scope. Unless the context indicates otherwise, a reference in a claim to the number of instances of an element, be it a reference to one instance or more than one instance, requires at least the stated number of instances of the element but is not intended to exclude from the scope of the claim a structure or method having more instances of that element than stated. The word "comprise" or a derivative thereof, when used in a claim, is used in a nonexclusive sense that is not intended to exclude the presence of other elements or steps in a claimed structure or method.