The definition of GPON

GPON (Gigabit-Capable PON) technology is based on standard ITU-TG.984.x the latest generation of broadband passive optical access standards, with high bandwidth, high efficiency, large coverage, rich user interface and many other advantages, is large Most operators deemed to achieve broadband access network business, comprehensive transformation of the ideal technology.

GPON standards

GPON first proposed in September 2002 organized by the FSAN, ITU-T on this basis in March 2003 completed the ITU-T G.984.1 and G.984.2 for the development, in February 2004 and in June completed the G.984.3 of standardization. And ultimately formed a family of GPON standards.

The basic structure of the device based on GPON technology with existing PON similar, but also by the central office OLT, the client's ONT/ONU, ODN and network management system before connecting the two devices by a single-mode optical fiber and passive optical splitter consisting of components.

PON standard for other purposes, GPON standard provides an unprecedented high bandwidth, downlink rate of up to 2.5Gbit/s, which can adapt to asymmetric characteristics of broadband data services market. Provides full-service QoS guarantee, while carrying ATM cells and (or) GEM frame, there is a good level of service, the ability to support QoS guarantees and full service access. When carrying the GEM frame, TDM traffic can be mapped to GEM frame, using the standard 8kHz (125μs) frames can directly support TDM services. As a carrier-class technology standards, GPON also provides protection mechanisms and full OAM capabilities on the access network level.

In the GPON standard, clearly defined types need to support business data services (Ethernet services, including IP business and MPEG video streams), PSTN service (POTS, ISDN services), dedicated lines (T1, E1, DS3, E3, and ATM services ) and video services (digital video). GPON Multi service mapping to ATM cells or GEM frame transmitted, for various business types can provide the appropriate QoS guarantees.

GPON networking

Currently GPON networking has mainly FTTH/O, FTTB+LAN and FTTB+DSL three.

1) FTTH/O for the fiber to the home / office. After the fiber intake too much light is directly connected to the user's ONU, ONU for a user to use a high bandwidth, cost is also high, usually for high-end users and business users.

2) FTTB+LAN is fiber to the building, then through the large-capacity ONU (called MDU) access to the different services multiple users, so multiple users share the bandwidth resources of an ONU, low bandwidth per person, the cost is low general for low-end or low-end residential business users.

3) FTTB+ADSL is fiber to the building, then the way will be ADSL service access multiple users, is a multi-user shared an ONU, bandwidth costs and customer base are similar FTTB+LAN.

GPON downlink speeds

GPON downlink maximum rate of 2.5Gbps, the behavior 1.25Gbps, the maximum splitting ratio of 1:64.