FTTH passive optical networks and fiber plant design

With extraordinary increase of bandwidth requirement nowadays, service providers are compelled to push fiber deeper into the access networks in order to be able to offer the emerging services that customers are demanding. The economic aspects from the business side also put pressure on operators to deploy single network for multiple applications in order to maximize profitability. There are various technologies used today to increase the capacity of the access network. Fiber-To-The-Home (FTTH) utilizing ATM Passive Optical Networking (APON) has been developed for and field-tried in numerous networks all over the world. The advantages of APON solution lies in its future proof fiber based access technology (high bandwidth and long service life). Fiber and passive components used in the network are very reliable and low in the maintenance cost. The APON technology is standardized in ITU-T G.983, which is originated from Full Services Access Network (FSAN) initiatives. It supports multiple applications and provides powerful quality of service (Qos). In this paper, the requirements for APON FTTH network architecture, transport protocol and operation are examined in line with G.983 standards. The comparisons of APON to other existing high data rate access network solutions are then briefly discussed. Case studies of APON FTTH field trials are used as examples. These trials represented current status of APON FTTH development in US, on both network system elements and fiber plant components. A complete picture of APON FTTH network system and Outside Plant (OSP) design from CO to the residential homes is illustrated by these field trials. Discussions are given on topics related to APON FTTH system elements, such as OLT/ONT design, lifeline support, optical power budget and operation/fault management. Considerations regarding the design and deployment of OSP components focus on the configuration and construction of the fiber plant. Common issues related to field installations such as trouble shooting of fiber plant through splitter point, drop management, and long term reliability, etc. General design guideline on APON system and OSP requirements will be outlined based on the experience gained through limited deployment and field trials. Advances in APON technology in the near future will be debated at the end.