# Design and Implementation of a Passive Optical Network for a Small Town +
## 4 Results
* Each PON box is permanently labeled with the designations specified in the FDP on the outer and inner sides of the lid. * Before closing the boxes, the correct formation and placement of the optical fibers is checked according to the instructions in order to avoid damage when closing it. * Protective caps are placed on all connectors (adapters) that are not connected. This method is suitable for housing cooperatives and entrances to blocks of flats in settlements with over 10 thousand inhabitants (mandatory for over 30 thousand inhabitants), and for resort areas where overhead cables are not allowed. It is important to note that special building permits (agreements with building owners) are required when connecting the building to a trench and for internal optical cabling. The connection to the interior of the building is made underground (a hole in the foundation) or at the level of the first floor (with an outlet pipe) depending on the characteristics of the building. The number of fibers in the cable should be four if the households in the entrance are less than or equal to 32. For more than 32 households in the entrance, the building is connected with a fiber optic cable with 12 fibers. Figure 3: Connection of buildings with five or more households with the PON. During the installation and configuration of PON, the second-level splitters are located in PON-ES boxes installed in the common areas of the buildings. The connection configuration is as follows:  
* Each box serves as a terminal element for FITH connection cables containing 4/12 OF, which are terminated directly in the PON-ES (passive optical network equipment splice). * The splitters used, the connection method, and the activated fibers are implemented in accordance with the established standards for passive optical networks (PON) [11]. * A single distribution splice connects up to 4-5 building entrances, and is installed according to the optimized route layout. * The connection boxes (PON-ES) are installed in the common area of the building, while complying with the requirements for operational maintenance and long-term reliability. * Fibers are connected to the second level splitter located in the PON-ES module via pre-installed LC/APC connectors (LC--lucent connector, APC--angled physical contact), which ensure quick installation and stable optical connections. One splitter is provided for every 16 households (single-family homes). Full coverage of the households is achieved with two 1:8 splitters in the connection socket. One OLT port can supply 64 households without a zero-level splitter and can cover 128 households with such a splitter (Figure 4, Table 3). Figure 4: Installation of the PON boxes in a building with a level 2 splitter and distribution splice closure. As a result of the installation, its flexibility and scalability are demonstrated as well as an effective management of branching logic at the secondary access level. When there is an existing above-ground infrastructure, such as private houses or hotels, deploying aerial fibers is a cost-effective and efficient way of implementing FTTH. This approach requires special building permits and agreements with building owners due to the routing of the overhead cable. The number of fibers in the distribution cables is between 12 and 72, depending on the number of users. Optical cables with a capacity of 12-24-72 optical fibers with a non-metallic self-supporting power element, a central element, and several tubes around it are used. The suspension is performed with standard fittings for these purposes. During the process of implementing a cable connection from the splitter to the end-user premises, several practical and structural requirements need to be observed to ensure reliability and ease of installation in overhead FTTH deployments:  
* The drop cable must allow easy separation of the power element and the optical cable element to facilitate handling during installation.