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VAI N AVI

VAI N AVI. Connecting to the world. Company Profile.

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VAI N AVI

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  1. VAINAVI Connecting to the world

  2. Company Profile VAINAVI INDUSTRIES LIMITED is a class “B” Internet Service Provider licensed by the Department of telecommunications, Govt. of India. We provide next generation broadband services that enable fast, simple and reliable communications, anytime, anywhere within our coverage area. Our unique, advanced network not only creates a new communications path into the home or office, but also facilitates access to information, interactive media content, applications and communications services away from the home or office. We also carry out the business of providing infrastructure for broadband and telecom Sector by facilitating them to carry Voice, Video & other forms of data. Vainavi Industries Limited (Class B ISP License Holder) Sun Constructions (Over Head Fiber Company) Vision Infracon Pvt. Ltd (Underground Fiber Company IP 1 License Holder)

  3. Why Fiber Today’s high data rate networks are all based on optical fiber the reason is simple (examples for demonstration sake) Twisted copper pair(s) 8 Mbps @ 3 km, 1.5 Mbps @ 5.5 km (ADSL) 1 Gb @ 100 meters (802.3ab) Microwave 70 Mbps @ 30 km (WiMax) Coax 10 Mbps @ 3.6 km (10BROAD36) 30 Mbps @ 30 km (cable modem) Optical fiber 10 Mbps @ 2 km (10BASE-FL) 100 Mbps @ 400m (100BASE-FX) 1 Gbps @ 2km (1000BASE-LX) 10 Gbps @ 40 (80) km (10GBASE-E(Z)R) 40 Gbps @ 700 km [Nortel] or 3000 km [Verizon]

  4. Why is fiber better ? Attenuation per unit length Reason for energy loss copper: resistance, skin effect, radiation, coupling fiber: internal scattering, imperfect total internal reflection so fiber beats coax by about 2 orders of magnitude e.g. 10 dB/km for thin coax at 50MHz, 0.15 dB/km l =1550nm fiber Noise ingress and cross-talk Copper couples to all nearby conductors No similar ingress mechanism for fiber Ground-potential, galvanic isolation, lightning protection Copper can be hard to handle and dangerous No concerns for fiber

  5. Why not fiber Fiber beats all other technologies for speed and reach But fiber has its own problems • Harder to splice, repair, and need to handle carefully • Regenerators and even amplifiers are problematic • More expensive to deploy than for copper • Digital processing requires electronics • So need to convert back to electronics • We will call the converter an optical transceiver • Optical transceivers are expensive • Switching easier with electronics (but possible with photonics) • So pure fiber networks are topologically limited: • Point-to-point • Rings

  6. Gpon Solution access network 1:2 passive splitter N end users core typically N=32 max defined 128 feeder fiber 1:4 passive splitter Implement point-to-multipoint topology purely in optics • avoid costly optic-electronic conversions • use passive splitters – no power needed, unlimited MTBF • only N+1 optical transceivers (minimum possible) !

  7. Gpon Advantages Shared infrastructure translates to lower cost per customer • Minimal number of optical transceivers • Feeder fiber and transceiver costs divided by N customers • Greenfield per-customer cost similar to UTP Passive splitters translate to lower cost • Can be installed anywhere • No power needed • Essentially unlimited MTBF (Mean Time Between Failures) Fiber data-rates can be upgraded as technology improves • Initially 155 Mbps • Then 622 Mbps • Now 1.25 Gbps • Soon 2.5 Gbps and higher

  8. Terminology downstream upstream NNI Optical Distribution Network Optical Network Units core splitter Optical Line Terminal UNI Optical Access Network Terminal Equipment Like every other field, PON technology has its own terminology • The CO head-end is called an OLT • ONUs are the CPE devices (sometimes called ONTs in ITU) • The entire fiber tree (incl. feeder, splitters, distribution fibers) is an ODN • All trees emanating from the same OLT form an OAN • Downstream is from OLT to ONU (upstream is the opposite direction)

  9. GPON Principles GPON obey the basic principles OLT and ONU consist of • Layer 2 (Ethernet MAC, ATM adapter, etc.) • optical transceiver using different ls for transmit and receive • optionally: Wavelength Division Multiplexer Downstream transmission • OLT broadcasts data downstream to all ONUs in ODN • ONU captures data destined for its address, discards all other data • encryption needed to ensure privacy Upstream transmission • ONUs share bandwidth using Time Division Multiple Access • OLT manages the ONU timeslots • ranging is performed to determine ONU-OLT propagation time Additional functionality • Physical Layer OAM (Operation, Administration, & Maintenance) • Autodiscovery • Dynamic Bandwidth Allocation

  10. Why a new protocol ? downstream upstream GPON has a unique architecture • (broadcast) point-to-multipoint in DS direction • (multiple access) multipoint-to-point in US direction contrast that with, for example • Ethernet - multipoint-to-multipoint • ATM(Asynchronous Transfer Mode) - point-to-point This means that existing protocols • do not provide all the needed functionality • e.g. receive filtering, ranging, security, BW allocation

  11. (multi)point - to - (multi)point Multipoint-to-multipoint Ethernet avoids collisions • by CSMA/CD (Carrier Sense Multiple Access)/ (Collision Detection) ) This can't work for multipoint-to-point US GPON • since ONUs don't see each other • And the OLT can't arbitrate without adding a roundtrip time Point-to-point ATM can send data in the open • although trusted intermediate switches see all data • customer switches only receive their own data This can't work for point-to-multipoint DS GPON • since all ONUs see all DS data

  12. GPON history 2001 : FSAN initiated work on extension of BPON to > 1 Gbps Although GPON is an extension of BPON technology • and reuses much of G.983 (e.g. line code, rates, band-plan, OAM) • decision was not to be backward compatible with BPON 2001 : GFP developed (approved 2003) 2003 : GPON became G.984 • G.984.1 : GPON general characteristics • G.984.2 : Physical Media Dependent layer • G.984.3 : Transmission Convergence layer • G.984.4 : management and control interface • FSAN is Full Service Access Network • BPON is Broadband Passive Optical Network

  13. Types of Optical Fiber Popular Fiber Sizes Multimode Graded-Index Fiber Single-mode Fiber

  14. Multimode Dispersion 1 1 1 1 1 1 1 0 1 Dispersion limits bandwidth in optical fiber

  15. Single-Mode Dispersion 1 1 0 1 1 0 1 In SM the limit bandwidth is caused by chromatic dispersion.

  16. Optical Splitters

  17. Budget Calculations LB= ׀ PS׀-׀ PO׀ LB = Link Budget PS = Sensitivity PO = Output Power Example: GPON 1310nm Power: 0dbm Single-mode fiber Sensitivity: -23dbm } LinkBudget: 23db

  18. Typical Range Calculation Assume: Optical loss = 0.35 db/km Connector Loss = 2dB Splitter Insertion Loss 1X32 = 17dB Range Budget: 11Km

  19. Relationship between transmission distance and number of splits

  20. GPON Encapsulation Mode PLI (12b) Port ID (12b) PTI (3b) HEC (13b) payload fragment (L Bytes) A common complaint against BPON was inefficiency due to ATM cell tax GEM is similar to ATM • constant-size HEC-protected header • but avoids large overhead by allowing variable length frames GEM is generic – any packet type (and even TDM) supported GEM supports fragmentation and reassembly GEM is based on GFP, and the header contains the following fields: • Payload Length Indicator - payload length in Bytes • Port ID - identifies the target ONU • Payload Type Indicator (GEM OAM, congestion/fragmentation indication) • Header Error Correction field (BCH(39,12,2) code+ 1b even parity) The GEM header is XOR'ed with B6AB31E055 before transmission GEM (Generic Encapsulation Mode) GFP (Generic Frame Protocol) 5 B

  21. GPON US considerations GTC fames are still 125 msec long, but shared amongst ONUs Each ONU transmits a burst of data • using timing acquired by locking onto OLT signal • according to time allocation sent by OLT in BWmap • there may be multiple allocations to single ONU • OLT computes DBA by monitoring traffic status (buffers) • of ONUs and knowing priorities • at power level requested by OLT (3 levels) • this enables OLT to use avalanche photodiodes which are sensitive to high power bursts • leaving a guard time from previous ONU's transmission • prefixing a preamble to enable OLT to acquire power and phase • identifying itself (ONU-ID) in addition to traffic IDs (VPI, Port-ID) • scrambling data (but not preamble/delimiter)

  22. GPON Auto discovery Every ONU has an 8B serial number (4B vendor code + 4B SN) • SN of ONUs in OAN may be configured by NMS, or • SN may be learnt from ONU in discovery phase ONU activation may be triggered by • Operator command • Periodic polling by OLT • OLT searching for previously operational ONU G.984.3 differentiates between three cases: • cold GPON / cold ONU • warm GPON / cold ONU • warm GPON / warm ONU Main steps in procedure: • ONU sets power based on DS message • OLT sends a Serial_Number request to all unregistered ONUs • ONU responds • OLT assigns 1B ONU-ID and sends to ONU • ranging is performed • ONU is operational

  23. Failure recovery GPONs must be able to handle various failure states GPON • If ONU detects LOS or LOF it goes into POPUP state • it stops sending traffic US • OLT detects LOS for ONU • if there is a pre-ranged backup fiber then switch-over

  24. Dynamic Bandwidth Allocation MANs and WANs have relatively stationary BW requirements • due to aggregation of large number of sources But each ONU in a GPON may serve only 1 or a small number of users So BW required is highly variable It would be inefficient to statically assign the same BW to each ONU So GPON assign dynamically BW according to need The need can be discovered • by passively observing the traffic from the ONU • by ONU sending reports as to state of its ingress queues The goals of aDynamic Bandwidth Allocation algorithm are • maximum fiber BW utilization • fairness and respect of priority • minimum delay introduced

  25. GPON With Triple Play Offer on FTTH Technology SURF TALK WATCH

  26. What is triple Play One of the hottest trends in consumer telecom services is called the “residential triple play.” This is a bundling that combines three electronic services that nearly every home subscribes to. They are Digital CATV, telephony and High Speed Internet. CABLE TV INTERNET TELEPHONY

  27. Advantages of Triple Play • To provide technically efficient & Cost effective • Triple Play Service through GPON FTTH • Adds Value to the amenities • Seamless Network • Eliminates cable clutter & Jammed ducts • Intercom & security systems • One point of contact for all kind of services • Easy up gradation to future technologies • Expandable network • Easy maintenance • No electric power within network

  28. Typical Connectivity Diagram

  29. GPON on FTTB Technology ONT On Sharing

  30. GPON on FTTH Technology ONT at Individual House

  31. VAINAVI THANK YOU

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