By Xie Liansheng
The optical distribution network (ODN) is an essential FTTx element, accounting for 60 to 70% of an operator's total FTTx investment. Considering the massive CAPEX involved, ODN deployment facilitators are in demand.
During FTTB and FTTH deployment, ODNs typically employ P2MP (point-to-multiple-point) topology, as opposed to the simpler P2P (point-to-point) structure of their copper counterparts. With P2MP, split ratios and splitter locations greatly impact the total investment, thus requiring much more sophisticated planning & design. ODN deployment is also characterized by heavy engineering workloads and greater demands on project management. As fiber is more sensitive than copper, and more connection points are involved, the former is more prone to errors during construction, making ODN testing necessary before project acceptance.
Planning/design: Inefficient & error-prone
Field surveys are necessary after bandwidth models and access scenarios are determined as they help verify information for thousands of households by collecting and entering bulk data related to central office location, outdoor fiber distribution terminal location, ducting, and line resource distribution.
AutoCAD, as opposed to dedicated ODN-design software, is now used for most of these projects, making it impossible to effectively use an operator's existing resource data or GIS (geographic information system) information; thus, planning/design efficiency is low. For a certain ODN project involving 150,000 lines, despite GIS map availability, planning engineers still had to draw their maps & cabling routes using AutoCAD while calculating the optical power budget manually. The planning/design work was consequently completed about three months behind schedule, while a data error rate of about 3% was introduced through the aforementioned manual work while an additional 2% stemmed from manual entry of design data into the system. These errors made themselves known during deployment as certain elements had to be reworked.
Deployment without quality assurance
Optical fiber, which is thinner than human hair and less yielding than copper, demands great skill during the connection process; first attempts are often unsuccessful. To make things worse, checking & acceptance (C&A) on a single-line basis is onerous and tricky; a lack of viable batch C&A measures certainly doesn't help, either the effort involved or the cost. As a result, C&A for most projects fails to fully comply with related processes as mere sample tests or even no tests are carried out, leaving engineering troubleshooting for the service provisioning phase.
In addition, all network deployment information is entered into the resource database manually. After several individual construction tasks are carried out, information in the resource database may not be updated promptly, which may affect follow-up network operation & maintenance (O&M); a Huawei study of over ten operators shows an average ODN resource data error rate of about 20%.
Inadequate project management capabilities
ODN deployment involves numerous complex processes, including survey, design, civil engineering, duct laying, fiber laying & connection, indoor cabling, and C&A. Moreover, there are tight time constraints on the right-of-way (ROW) and home access.
As a result, key project team members, including the manager and planning engineers, must have extensive experience in large-scale network building and project management. However, such personnel are difficult to attract. Novices will have difficulty identifying critical project paths early, meaning that subsequent planning and division of work may not be done properly; they may also struggle with monitoring/control over task progress, risk identification, and timely adjustment during project implementation.
Enhanced design/plan efficiency & quality
To address bottlenecks and other problems with large-scale ODN deployment, Huawei has introduced its one-stop ODN integration service solution, which features a full set of standardized integration processes, as well as rapid, high-quality, end-to-end (E2E) delivery capabilities.
Based on the industry-leading GIS platform (Esri ArcGIS), Huawei launched the MDS6690 professional ODN planning/design software in 2011. Utilizing global GIS maps and online map platforms, MDS6690 features OLT, ODN, and MxU planning/design functionality. Planning engineers may import both GIS maps and existing network information so that design can be carried out in a more cartographic manner. In addition, the design software supports optical fiber routing, automatic display of vertical and horizontal building structures, and automatic E2E link-loss calculation.
The MDS6690 imports batch survey data along with data flows for construction and C&A; it also aligns design results with operators' resource management systems. It starts from planning/design and continues through the data chain over the entire ODN deployment process, thereby eliminating potential manual data entry errors at every step.
The MDS6690 also automatically generates various planning and design schemes that planning engineers can select, based on cost and network scalability. For a certain project in Southeast Asia, the MDS6690 enabled a 53% work efficiency increase for planning engineers over AutoCAD, while eliminating manual data entry errors.
Fast & efficient deployment
Huawei's ODN solution not only adopts advanced cabling techniques such as micro trenching and air-blown microcabling/ducting, but it also facilitates intelligent ODN optical-fiber management and ODN batch C&A.
Microtrenching – Fiber is laid in a shallow and narrow groove cut into a concrete or asphalt road surface, which makes the process timely, economical and discreet.
Air blown microcabling/ducting – Micro ducts form the infrastructure into which the fiber units are blown. This technique reduces upfront costs while enabling more efficient installation and scalability. However, preparation can be time-consuming and the overall costs are high. This technique is suitable when straight-line cabling distances between feeder and optical distribution sections exceed 1km.
Intelligent ODN optical-fiber management – Intelligent management is achieved by adding eID tag connectors and adapters to standard LC fiber connectors. Each eID number is 64-bit, ensuring unique identification on a global scale. Connector information and equipment ID are also included in the eID tag.
Huawei's iODN solution allows engineers to receive instruction sets from the MDS6690 planning/design tool through iField, a professional installation aid tool. Later, at the construction site, engineers can efficiently finish engineering implementation simply by connecting the iField to the iODN equipment via USB and then following the subsequent LED prompts.
After construction is completed, iField can be used to generate engineering confirmation sheets; it will automatically gather connection relationships and port states to determine whether or not instructions have been followed. It will also automatically upload engineering confirmation documents to MDS6690, which will then refresh the relevant design data, saving time & effort and ensuring accuracy. During project handover, MDS6690 design data may be imported into the operator's resource management systems and the U2000-O (the iODN network management system), which guarantees the accuracy of resource data sources.
Batch C&A – Multiple fiber links can undergo C&A at a single instance while OTDR tests and planning/design can be checked automatically. This method is highly efficient and accurate, and also makes data-link C&A feasible and cost-effective.
Huawei offers an intelligent ODN C&A tool that combines hardware and software. The software is installed on a PC or notebook while the hardware is comprised of OTDR and optical switches. Engineers can import design data into this tool and carry it to the site. They can then connect multiple optical fibers simultaneously and test them in batches using the software. This tool will automatically compare the OTDR test results and design data for every link, while importing data such as optical fiber length & link loss and automatically generating reports. Efficiency for ODN C&A can be increased 3 to 5 fold using this tool, while the engineer involved need no longer be senior.
Delivery team professionalism is critical
To ensure timely and effective delivery of ODN integration service project, the delivery team needs to consider all the relevant factors, including the project's scope, duration, and risks. A dedicated delivery team is required for every ODN project; it should consist of a project manager, account manager, planning engineer, implementation manager, site engineer, materials administrator, documentation controller, and implementation engineer. Work responsibilities and boundaries need to be clearly defined to better facilitate coordination between the different roles.
Huawei has more than 300 professional delivery managers, while its subcontractors are distributed worldwide. It also has more than a decade of experience in turnkey services and ODN deployment. Its ODN integration services have been utilized commercially by more than 50 operators worldwide, including Telefónica, Etisalat, Qtel, Maxis, and Vodafone Ghana. Huawei can customize its integration solutions to specific customer requirements and scenarios, and continuously improve the relevant service processes and tools, which enhances the delivery capabilities of its expert teams and reduces customer investment.
In a project carried out with Maxis, a Malaysian operator, Huawei doubled the design efficiency for the operator's engineers by introducing its professional planning/design software. In another project with Etisalat, it only took Huawei half a year to successfully cover 80% of Abu Dhabi's households. Thanks to iODN, both operators managed to increase their competitiveness, both in terms of brand and market.