As a new generation of optical fiber access technology, XPON has huge advantages in anti-interference, bandwidth characteristics, access distance, maintenance and management, etc. Its application has attracted great attention from global operators. XPON optical access technology is relatively mature EPON and GPON are both composed of central office OLT, user-side ONU equipment and passive optical distribution network ODN. Among them, ODN network and equipment are an important part of XPON integrated access, involving the formation and application of a new optical fiber network. Related ODN equipment and networking costs have become important factors restricting XPON applications.
Concept
At present, the industry’s generally optimistic xPON technologies include EPON and GPON.
GPON (Gigabit-CapablePON) technology is the latest generation of broadband passive optical integrated access standard based on the ITU-TG.984.x standard. It has many advantages such as high bandwidth, high efficiency, large coverage, and rich user interfaces. Operators regard it as an ideal technology to realize broadband and comprehensive transformation of access network services. The maximum downstream rate of GPON is 2.5Gbps, the upstream line is 1.25Gbps, and the maximum splitting ratio is 1:64.
EPON is a kind of emerging broadband access technology, which realizes the integrated service access of data, voice and video through a single optical fiber access system, and has good economic efficiency. EPON will become a mainstream broadband access technology. Due to the characteristics of the EPON network structure, the special advantages of broadband access to the home, and the natural organic combination with computer networks, experts all over the world agree that passive optical networks are the realization of “three networks in one” and the solution to the information highway. The best transmission medium for the “last mile”.
The next generation PON network system xPON:
Although EPON and GPON have their own different technologies, they have the same network topology and similar network management structure. They are both oriented to the same optical access network application and are not non-convergence. The next-generation PON network system xPON can support at the same time. These two standards, that is, xPON equipment can provide different forms of PON access according to the different needs of users, and solve the problem of incompatibility of the two technologies. At the same time, the xPON system provides a unified network management platform that can manage various business needs, realize full-service (including ATM, Ethernet, TDM) support capabilities with strict QoS guarantee, and support downstream cable TV transmission through WDM; at the same time, it can automatically identify EPON, GPON Access card is added and withdrawn; it is truly compatible with EPON and GPON networks at the same time. For network managers, all management and configuration are for business, regardless of the technical difference between EPON and GPON. That is to say, the technical implementation of EPON and GPON is transparent to the network management, and the difference between the two is shielded and provided to the upper-layer unified interface. A unified network management platform is one of the biggest advantages of this system, which truly realizes the unification of two different PON technologies on the network management level.
Main parameters and technical indicators
The main parameters of the xPON network are as follows:
●Multi-service support capabilities: to achieve full-service (including ATM, Ethernet, TDM) support capabilities with strict QoS guarantee, for business optimization, support downlink cable TV transmission through WDM;
●Automatic identification and management of EPON and GPON access cards;
●Support 1:32 branch ability;
●The transmission distance is not more than 20 kilometers;
●Upstream and downstream symmetric line rate 1.244Gbit/s. Support port traffic statistics function;
●Support dynamic and static bandwidth allocation function.
●Support multicast and multicast functions
The main technical indicators of xPON network:
(1) System capacity: The system has a large-capacity IP switching core (30G) to provide a 10G Ethernet network interface, and each OLT can support 36 PON networks.
(2) Multi-service interface: Support TDM, ATM, Ethernet, CATV, and provide strict QoS guarantee, which can fully include existing services. It truly supports the smooth upgrade of the business.
(3) System high reliability and availability requirements: The system provides an optional 1+1 protection switching mechanism to fully meet the requirements of the telecommunication network for network reliability, and the switching time is less than 50ms.
(4) Network range: configurable 10,20Km network path, fully meet the requirements of the access network.
(5) Unified system management software platform: For different access methods, have a unified network management platform
Structure
Passive optical fiber network system is an optical fiber broadband transmission system composed of optical line terminal (OLT), optical distribution network (ODN), and optical network unit (ONU), referred to as PON system. The PON system reference model is shown in Figure 1.
The PON system adopts a point-to-multipoint network structure, uses a passive optical distribution network as a transmission medium, uses a broadcast mode in the downlink, and a TDM working mode in the uplink, which realizes single-fiber bidirectional signal transmission. Compared with the traditional access network, the PON system can reduce the consumption of access to the computer room and access optical cables, increase the network coverage of the access node, increase the access rate, reduce the failure rate of lines and external equipment, and improve the reliability of the system. At the same time, it also saves maintenance costs, so the PON system is the main application technology of the NGB two-way access network.
According to the different signal transmission formats of the system, it can be referred to as xPON, such as APON, BPON, EPON, GPON and WDM-PON. GPON and EPON have been widely deployed around the world, and there are also large-scale applications in the transformation of radio and television two-way networks. WDM-PON is a system that uses independent wavelength channels between OLT and ONU to form a point-to-point connection. Compared with TDM- such as EPON and GPON, PON and WDM-PON have the advantages of high bandwidth, protocol transparency, safety and reliability, and strong scalability. They are the future development direction. In the short term, due to the complex principles of WDM-PON, the higher device prices, and the high system costs, it does not yet have the conditions for large-scale applications.
The main technical indicators of xPON
①System capacity: The system has a large-capacity IP switching core (30G), provides a 10G Ethernet network interface, and each OLT can support 36 PONs;
②Multi-service interface: support TDM, ATM, Ethernet, CATV, and provide strict QoS guarantee, can fully absorb the existing business, and truly support the smooth upgrade of the business;
③ System high reliability and availability requirements: The system provides an optional 1+1 protection switching mechanism to fully meet the requirements of the telecommunication network for network reliability, and the switching time is less than 50m;
④Network range: 10-20km network diameter can be configured to fully meet the requirements of the access network;
⑤Unified system management software platform: For different access methods, it has a unified network management platform.
HUANET produce a lot of models of xPON ONU, xPON ONT, include 1GE xPON ONU, 1GE+1FE+CATV+WIFI xPON ONT, 1GE+1FE+CATV+POTS+WIFI xPON ONU, 1GE+3FE+POTS+WIFI xPON ONT. We also provide Huawei xPON ONT.
Post time: Jun-24-2021