Basic knowledge of FTTH,

1, an overview of the basic knowledge of FTTH light into the copper back the idea is to change the existing copper access primarily for the construction of the model, the optical fiber to the client as far as possible, in view of the different scenarios using FTTH, FTTB, FTTN different patterns. Implementing light into the copper work can significantly improve access bandwidth, improve the network's ability to support business, fiber access characteristics of long transmission distance, high access bandwidth, transmission of good quality, and low maintenance cost, is the direction of the access network, enhance the core competitive ability of China telecom. 2, broadband speed policy - — Building model city area to the advance of the cable to the new building, mainly based on the construction pattern of PON FTTB + LAN; In the developed area, promoting FTTH/FTTO rural areas covered by appropriate USES cable way to extend to administrative villages and large natural villages of the cable, mainly adopting FTTN + ADSL2 + construction mode existing network retrofit should be fully aware of the network evolution and bandwidth increase, mainly based on PON FTTB, FTTN transformation model, encourages business developed areas to adopt FTTH mode to upgrade. City copper network transformation should one pace reachs the designated position, distance control within 500 m rural copper distance control in 1. 5km- 2 km, for copper theft serious aging, switches, line moved to the urgent demand or copper back in, should be mainly based on PON FTTB ( Urban areas) /硬件( In rural areas) Band down transformation patterns at the same time, for can't meet the demand of business development of the traditional LAN village renovation, voice access mode remains unchanged, broadband access should be mainly based on PON FTTB + LAN mode transformation access cable network and ODN network is the basis of the size of FTTH deployment and key, should do well in cable network and ODN network access to the overall planning, promote wider coverage and to the user side of the cable network is outspread, accelerate urban areas ( Including the county) Establishment and perfecting of optical fiber into the building, ODN construction specification and process 3, FTTH overview - — Broadband optical fiber access, and the concept of FTTX, FTTO, FTTH FTTP come to fruition in the manner that the entire optical fiber end user's access, including home users and enterprise users, user access devices ( Such as ONU) By a single user ( Family, business, or office) Exclusive depending on the location of the optical fiber to the user side, the application of broadband optical access network way, The construction mode) Including the following, these patterns are collectively referred to as FTTx - FTTNFiberToTheNode, fibre to the node - FTTZFiberToTheZone, to the community - FTTCabFiberToTheCabinet, fiber optic fiber to box - FTTCFiberToTheCurb, fiber to the curb - FTTBFiberToTheBuilding, fiber to the building - FTTPFiberToThePremise, optical fiber to the user base - FTTHFiberToTheHome, fiber to the home - FTTOFiberToTheOffice, fiber to the office 4, FTTH overview - — The main PON technology n currently used PON FTTH technology for EPON and GPONPON lIEEE802 EPONGPON characteristic. Put forward three standard lFSAN, itu-t T Ethernet lGEM packaging standardization l l simple technology, low cost technology is complex, l cost slightly higher l better l standard is still in perfect l mature technology, has size l have tried more IEEEEPONITU - commercial deployment and small-scale technology 1 TGPON down line rate. 25 g2。 5 g uplink rate of 1. 25 g1。 25 g or 2. 8 b / 10 BNRZ (5 g line coding +加扰) Shunt transmission distance of 20 6464 km20km data link layer protocol Ethernet, simple EthernetoverGEMand TDMoverPacketTDMoverGEM/orATMTDM support ability, adopted 125 us frame length and timing mechanism, can more easily support NativeTDM EthOAM (voice service business and running and managing Optional SNMP) PLOAM + OMCI downlink data stream encryption triple agitation AES system cost low (1) definition of overview, ODN ODN: optical distribution network ( ODN) Lies between OLT and ONU, the delimited interface for close to the OLT optical connector after the S/R reference points and ONU optical connector before the R/S reference point. The role of ODN: optical distribution network ( ODN) An optical line terminal ( OLT） And multiple optical network winding unit ( ONU） Connect, providing two-way transmission of optical signals. ODN composition: from the point of the network structure, the light distribution network composed of feeder optical fiber, optical divider and feeder, respectively is composed of different passive optical components, main passive optical components are: low fiber optic cable: metropolitan area optical cable, indoor scheduling cable, butterfly fiber optical divider low, such as low optical fiber wiring equipment: ODF, MODF, OCC, connector box, fiber boxes, light fiber box, low fiber connector: activities at the scene of the mechanical, optical connector, optical fiber connection and etc