When we walk in residential areas and urban villages, we often see advertisements about various types of broadband. The three major operators are full of their advertisements. They only need 88 yuan for broadband to send mobile phones, and a piece of broadband is free to take home. In fact, there are various conditions to be put into the contract. Deep Pit Dou E’s Injustice”. The quality of broadband is closely related to all aspects of work and life. Often, good broadband brings high efficiency and a good mood, while bad broadband is troublesome, worrying, and sad every day. Today, I will take you to understand how broadband is networked. Broadband is professionally called fiber-to-the-home, and there is another term called resident network. That is, China’s “Broadband China” strategy proposed by the State Council in 2012, which is also one of the national strategies. Since then, China’s broadband has entered a period of rapid development.
Fiber to the Home (FTTP), also known as Fiber to the Home (FTTH), refers to a broadband telecommunications system. Fiber to the home realizes the function of triple play. Triple play refers to the integration of computer network, radio and television network and telecommunication network to form a fully digital and unified network system that supports all services including data, video and voice. communication services delivered to homes or businesses. At this stage, community owners are increasingly demanding information and communication, especially for high-speed access means, and the application of optical fiber has naturally entered the attention of everyone. Optical fiber not only has large frequency bandwidth and communication capacity, but also can effectively and conveniently realize the infinite superposition of application services, which can better meet the development needs of future broadband integrated services, and fundamentally avoid the waste of resources caused by repeated investment. For the smart community, the optical fiber is directly connected to the owner’s home, and the optical network unit (ONU) is installed in the owner’s home. Household (FTTH) technology has the characteristics of providing ultra-large bandwidth, easy maintenance and installation, and is generally considered by industry insiders and experts to be the main form of broadband access network in the future.
EPON topological structure has bus structure, tree structure, ring structure and star structure. For smart cells with high access rate, a tree-structured network should be used during construction, which is beneficial to reduce access costs. The tree-structured EPON adopts a point-to-multipoint (P2MP) structure of a single-fiber bidirectional optical access network in terms of transmission, and its topology is shown in the figure below.
OLT (Optical Terminal Equipment) is a terminal equipment used to connect optical fiber trunks. Its function is to provide the interface between the access network and the local exchange, and completely separate the exchange function of the exchange from the user access. On the one hand, the signals carrying various services are aggregated at the central office and sent to the access network according to a certain signal format for transmission to end users; on the other hand, signals from end users are sent to various service networks according to service types. middle.
ONU (Optical Network Unit) is a device that gets in touch with the network terminal OLT through the POS passive optical splitter. The function of the device is to terminate the optical fiber from the OLT and place it at the customer premises to provide the access network with the interface of the terminal equipment on the user side. The network end of the ONU is an optical interface, and the user end is an electrical interface, so it has electrical/optical and optical/electrical conversion functions, as well as corresponding monitoring and maintenance functions.
OND (Optical Distribution Network) is a general term for the lines and equipment set between the Optical Line Terminal (OLT) and the Optical Network Unit (ONU) in the optical fiber access network to distribute optical signal power and provide optical power between the OLT and the ONU. The physical channel through which the signal is transmitted.
The EPON networking mode not only simplifies the wiring and routing in the community, but also reduces the repetitive and complicated wiring construction of each system. At the same time, because the optical fiber can provide a large bandwidth, the access network can better realize cable TV broadcasting, broadband and telephone. access, as shown in the figure below.
The entire FTTH broadband access network consists of three parts: OLT, residential fiber network, and ONU. OLT is a multi-service centralized control unit, which is mainly responsible for bandwidth control, authentication management, fault capture, and converts data and video broadcast signals into optical signals for distribution. The OLT supports the division of virtual private networks (VLANs). The community optical fiber network adopts single-mode optical fiber. The ONU is a multi-service subscriber unit that completes photoelectric signal conversion in the user’s home, providing users with high-speed data, bypass voice and video services. In view of today’s household living equipment, in the functional configuration of ONU, it is best to ensure that each household has 4 network ports (each network port rate is about 100Mbit·s-1), 2 telephone ports and a cable TV port. Each network port, telephone port and TV port can be controlled individually, which is convenient for billing and management.
Using EPON networking, the integrated three networks provide their own services for the residents of the community in a new way, and also build a mature and open access platform for the community, so that the subsystems of the smart community can play their roles in a coordinated and unified manner. .
To sum up, the optical fiber to the home is very simple. The construction process: drawing familiarity → on-site verification → optimization plan → equipment coding → floor pipe wiring → trunk wiring → distribution box installation → equipment room decoration → ODF cabinet installation → label identification → fusion fiber → Optical fiber test → print completion documents → acceptance → enter the maintenance period → completion settlement → final inspection, the project is over, and everyone is safe.