By Liu Huaqing
Huawei FTTx O&M solutions enable timely, comprehensive network planning/deployment, while enhancing service provisioning efficiency and simplifying daily maintenance.
O&M challenges during the FTTx lifecycle
With broadband services and subscriber demands ever growing, FTTx has emerged as the optimal architecture for fixed operators. However, as most operators lack experience with this cutting-edge technology, FTTx network deployment, particularly on a large scale, remains challenging throughout the process.
Inefficient ODN planning and deployment
Compared with copper networking, optical distribution network (ODN) planning is much more complex, thanks to the point-to-multiple point (P2MP) topology typically employed, which necessitates comprehensive consideration of deployment scenarios, costs, optical splitter protection, scalability, and engineering survey information. More importantly, operators also need to bear in mind factors related to the evolution to next-generation PON technologies.
The network building itself is also more challenging and error-prone, as fiber is more fragile than copper and a greater number of connection points are needed. Comprehensive testing should be carried out before a project is considered completed. Unfortunately, the workload and skills required are a serious barrier.
Massive MxU deployment
During FTTB/C deployment, a large number of small MxU boxes must be installed close to the user side, as opposed to the ADSL deployment scenario where access equipment is placed and managed primarily in central offices. Naturally, this makes FTTx project delivery more complicated and demanding, not just in terms of logistics and planning but in sheer workload, as the number of physical units deployed is increased at least ten fold.
Engineers often have to climb poles, scale walls, and wade through other unpleasantness, with a laptop in tow, to install these units; there's also a lot of driving involved, which can really pile up the miles, fuel bills and man hours, and that's just for deployment. Multiplying this by a large number of updates makes FTTx seem downright daunting, both in terms of O&M and TTM.
Slow service provisioning
As the scale of an FTTH network increases, so does the number of optical network terminals (ONTs). If the IT system does not support automatic activation and configuration of FTTx services, manual ticket distribution is the only choice, which means that resources must be pre-selected, also manually. Clearly, such a method is not viable if an operator wants to be omnipresent and up-to-date.
Automatic service activation, removal, suspension, restoration, modification, and porting of voice, broadband, and IPTV services under different FTTx service scenarios are clearly in demand, as manual operation for all of the above would strain the O&M resources of even the largest operator.
Difficulties in fault demarcation and assignment
When China Telecom Shanghai (Shanghai Telecom) was at the early stage of FTTx development, its primary challenges lied in user-end installation. As the subscriber base surpassed 5,000, fault diagnosis emerged as a key drag on network development.
This problem started with the service hotline. There was no pre-processing tool for front-line customer service staff, so most complaints were passed to O&M engineers for troubleshooting, who found it difficult to distinguish office-end, optical-fiber-line, and terminal-end faults, resulting in a laborious process of elimination that triggered even more complaints. Even after the fault's general vicinity was determined, a plethora of equipment and connections, spread out over a large area, further hindered the process, as tools for determining a fault's precise location were unavailable.
Complex ODN O&M
An optical distribution network (ODN) enables line resource data management, yet it is passive in nature. Data from the resource database becomes faulty if there is a breakdown in the process or a non-compliant operation. Based on a Huawei study of 10+ operators, ODN resource data has an average error rate of about 20%. Inaccurate data is retrieved during the processes of service activation and maintenance, which makes daily provisioning and troubleshooting more difficult.
Rapid deployment, easy O&M
Huawei has introduced a series of industry-leading O&M solutions to facilitate FTTx deployment and O&M. This series exhibits two distinct features. Firstly, it continuously maintains FTTx network resources, services, and information, while solving O&M problems for each phase of network deployment/operation. Secondly, the solution consists of multiple products or tools specialized for each phase. These tools focus on different areas yet work together to jointly complete various O&M tasks.
ODN planning and deployment
Huawei's proprietary professional ODN planning & design service, which is based on the industry-leading GIS platform, facilitates both high- and low-level design. It automatically generates route plans as well as various planning & design schemes that allow clear comparison between them.
This tool also fully takes into account various factors such as network building requirements, site conditions, and engineering survey results, so that engineers can produce an optimal design plan that ensures reasonable initial investment as well as smooth upgrade.
Operators can be assured of standardized and efficient design & implementation solutions, which lay a solid foundation for efficient O&M. This ODN service has been selected by more than 50 operators around the world.
Batch MxU pre-deployment
Huawei's batch MxU pre-deployment solution is designed to tackle the difficulties of massive MxU deployment for FTTB/C. With this solution, engineers need only create a pre-deployment Excel spreadsheet and import it into the U2000 network management system (NMS) before MxU deployment, as opposed to completing configuration through the command line.
Onsite installation is also far simpler as engineers need not bring their laptops for onsite tool calibration. Finally, checking & acceptance can be done remotely by batch via the U2000. Now that the China Telecom Group has widely implemented this solution, only one site visit is required for batch deployment, while software commissioning is thirteen times more efficient.
E2E service provisioning
The Huawei U2000 NMS facilitates both commissioning and automatic service provision. For Shanghai Telecom, the NMS provides northbound interfaces, while the IT system configures and supplies it with parameters. The NMS then finishes configuration to activate services one by one. It also neutralizes vendor compatibility issues, while featuring networking flexibility, fewer parameters and clearer layers.
For Shanghai Telecom's "bridging+voice" ONT, the OSS activates services via the U2000. For the "SFU+HG" ONT, the OSS implements single family unit (SFU) layer-2 service channel configuration via the U2000, and then configures home gateways through the ITMS to activate services. Currently, Shanghai Telecom is able to complete installation, indoor cabling and service activation within three days, at a maximum handling capacity of 3,000 subscribers per day.
Huawei's FTTx O&M solution also features iODN, which not only enables automatic provisioning of access terminals at the service provisioning phase, but also prompts the ODN management system through automatic ticket distribution to assist in the efficient configuration of ODN optical routes.
Such an electronic-based E2E provisioning mode overcomes the pitfalls of printed ticket transfer and non-closed-loop management by enabling automatic ticket return, automatic verification, and plan data correction.
Daily O&M assurance
O&M assurance is always an operator priority. Huawei's O&M assurance solution integrates all Huawei FTTx O&M products and subsystems, including the N2510 FTTx O&M assurance system, the U2000 NMS, the TMS1000 terminal management system, and the ODN management system. These products interact and collaborate with each other to enhance operators' daily assurance efficiency and quality.
- Fault pre-handling & one-touch fault demarcation
Complaint handling typically begins with customer service staff and moves through second- and third-line maintenance engineers. This is a long process that is best avoided through front-end complaint resolution.
Designed to enhance front-end personnel fault resolution competence, Huawei's N2510 ITS makes southbound connections to the U2000 for access to the NMS, N2510 OLS, TMS1000, and ODN management system, to receive detailed information concerning OLT equipment, ODN lines, terminals, and resources. It then carries out fault diagnostics, drawing on the collected experience of a case archive, which enables one-touch fault location.
The N2510 also supplies a script that service center staff can follow so that simple faults (particularly home network faults caused by improper use) are resolved right away, before maintenance personnel are consulted.
Fault location precision is seven-sections for FTTB/C and six-sections for FTTH. Based on statistics from a citywide branch of China Telecom, fault diagnostics are up to 85% accurate, thanks to its built-in case archive and analysis capabilities.
If faults occur outside the central office, the Huawei N2510 OLS performs precise ODN fault diagnosis through the optical time domain reflectometer (OTDR), based on equipment operation information. If faults must be identified to an interior/exterior precision, operators may install fiber Bragg grating (FBG) at those points. Currently, Huawei's proprietary OTDR can operate a full 1:64 line split to directly test optical-fiber cables within the home at an accuracy of within three meters.
- Timely troubleshooting & intelligent early warning
Huawei's FTTx O&M assurance solution also provides resolution and verification functionality. The U2000 supports ONU plug-and-play once an ONU fails and needs to be replaced.
After a fault is fixed, tools such as the U2000 and N2510 ITS also provide various verification measures to verify fault recovery and facilitate closed-loop processing. In addition, the Huawei FTTx O&M assurance solution provides fault resolution measures such as automatic service data restoration for board replacement, malicious customer feedback isolation, and automatic ONU restart after overheating.
Intelligent early warnings are indispensable to proactive O&M. Modules such as the ITS & OLS for the N2510 provide early warnings for faults in their respective fields. These systems gather and monitor data for relevant parameters and compare them against pre-set early-warning thresholds.
- Professional evaluation & optimization to ensure QoS
For copper networks that supplement FTTB/C, the N2510 AOS provides line evaluation & optimization functionality prior to service provisioning and upgrade. For pre-service-provisioning evaluation, it collects parameter data such as uplink/downlink rate, line length, open/closed line state, background noise, and line attenuation, through a series of line test results to evaluate if the target rates for the lines in question can be reached, which provides a basis for service activation.
The N2510 AOS can also pre-evaluate line readiness, in terms of rates and stability, to support service upgrade. It employs technologies such as DLM, DSM, VN, and vectoring to automatically identify the ideal line optimization scheme, ensuring that connections are always in their best state.
Huawei iODN is an intelligent optical fiber management solution designed to alleviate workload pressure and avoid manual data entry errors, making widespread FTTH deployment significantly easier.
The iODN establishes correct optical-fiber connections and manages them to ensure accurate maintenance, maintenance efficiency, and simplified O&M. Through automatic recognition of and data gathering for ODN fiber connection information, iODN reduces the workload while eliminating manual entry errors.
It also enables automatic search and location of optical fibers and ports through the U2000 ODN management system, the iField handset tool, and the intelligent port indication functionality of various distribution devices, thereby increasing the O&M efficiency and ensuring sustainable operation and management of large-scale FTTH networking.
The Huawei FTTx O&M solution has been successfully deployed by more than 30 operators all over the world, including China Telecom, China Unicom, China Mobile, France Telecom, and Telekom Malaysia.