The term FTTX simply states that it is an optical fiber connection network, that is, the use of optical fiber access to provide a solution for the "last kilometer" of the access network, and does not limit what topology must be used and what method to implement. The appearance of PON makes FTTX's optical fiber access possible. Because PON has low cost and simple operation and maintenance, it has almost become synonymous with FTTX technology. People have habitually equated PON with FTTX. At present, there are three types of PON technologies that have been commercialized to implement FTTX: APON/BPON, EPON, and GPON. Today, Leitong Technology focuses on telling you about the first APON/BPONA.
PON/BPON is the earliest passive optical network technology that was standardized and commercially available. BPON was originally called APON. ATM was used as the carrying protocol. The downlink transmission was continuous ATM stream with a bit rate of 155.52 Mbit/s or 622.08 Mbit/s. The uplink transmission is a burst form of ATM cell at a rate of 155 Mbit/s. APON/BPON has a dedicated physical layer operation management and maintenance(PLOAM) element inserted into the data stream, so it has a rich management and maintenance function.
The key technologies for implementing APON/BPON include multiple access and access control technologies(including ranging, bandwidth allocation, etc. when using TDMA uplink access), burst signal sending and receiving technology, fast bit synchronization technology, and security and confidentiality. APON/BPON is characterized by multi-service support and flexible networking capabilities. BPON's support for multiple services can be expressed in terms of a rich business interface. APON/BPON can support TDM-E1 / DS3, ATM and 10/100Base-T interfaces. The flexible topology of the APON/BPON system reflects the flexibility of the device in expansion and upgrade, and can form star, tree, or Bus-type networks.
However, the APON/BPON system has two major shortcomings: one is the low data transmission efficiency, and the other is the complexity of adapting and providing services on the ATM layer. Transferring data using APON/BPON also requires conversion between P and ATM elements and SONET/SDH formats, resulting in low efficiency, technical complexity, and high cost. After EPON and GPON technology commercial 4L2 _, the new FTTX network basically no longer uses APON/BPON technology. Therefore, this chapter then introduces FTTX's network solutions and no longer introduces APON/BPON.
Press the next few days, Leitong Technology will share EPON and GPON with the characters, welcome to call for advice: 13510735483