Basics of Optical Network Architecture, PON & GPON


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Our Team's University Project | A short presentation based project regarding optical fiber communication in which basics of Optical Network Architecture, PON & GPON were discussed.

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Basics of Optical Network Architecture, PON & GPON

  1. 1. Syed Shujat Ali 1421-311065 M Masoud Ahmad 1421-211016 Numan Ahmad Naseer 1421-211
  2. 2. • Architecture Of Optical Access Network • PON • GPON
  3. 3. From the architecture diagram, the optical access network comprises the following scenarios: 1. FTTB scenario 2. FTTC & FTTCab scenario 3. FTTH scenario
  4. 4. • Fiber to the Building , is the deployment of fiber (optical) cable to a specific location within a building, then connected to the buildings existing copper cable facilities. • This deployment is also referred to as : i. FTTB (Fiber to the Basement) ii. FTTB (Fiber to the Business). • This deployment will be the typical for MTU’s. i. MTU :Business Multi-tenant unit ; providing a comparatively larger number of ports, including POTS, 10/100/1000BASE-T and DS1/T1/E1 ports.
  5. 5. • Fiber to the Curb , is the deployment of fiber close to the customer but not fully to the customers residence. i. MDU : Multi-dwelling unit ;providing a comparatively larger number of ports, including 10/100/1000BASE-T, VDSL2, and so on. • In this deployment the existing copper plant is still used to deliver service to the actual customer. • Following Scenarios Also Falls Under This Category i. FTTN (Fiber to the Neighborhood) ii. FTTC (Fiber to the Cabinet)
  6. 6. • Fiber to the Home is the complete deployment of fiber to the customers home, with replacement of there existing NID (Network Interface Device). i. SFU : Single family unit , providing a comparatively small number of ports, including following types: POTS, 10/100/1000BASE-T, and RF. • This replacement device is called an ONT (Optical Network Terminator). i. The ONT converts fiber-optic light signals to copper/electric signals.
  7. 7. • A passive optical network (PON) is a point-to-multipoint, fiber to the premises (FTTP) network architecture in which unpowered optical splitters are used to enable a single optical fiber to serve multiple premises • In Simple it uses passive optical splitters to serve many subscribers from one optical unit • A PON consists of i. Optical Line Terminal (OLT) at the Central Office (CO) ii. Number of Optical Network Terminals (ONTs)at customer premises
  8. 8. • Enormous information carrying capacity • Easily upgradeable • Ease of installation • Reduced O&M costs • Long distance reach • Secure • Immune to electromagnetic noise • Best suited for triple play services
  9. 9. • Evolutionary technology based upon BPON(Broadband passive optical network). • It supports higher rates, enhanced security, and choice of Layer 2 protocol (ATM, GEM, Ethernet). • GPON uses IP-based protocols to transfer data.
  10. 10. • Standardized by ITU-T G.984 . • Operates at 2.488 Gbps downstream and 1.244 Gbps upstream. • Practical fiber split ratios up to 1:64 (standard supports up to 1:128) • Distance between OLT and ONT/ONU can be up to 20 km. • GPON specifies QoS and management protocols required for triple-play services over the network. • Downstream security guaranteed with 128-bit AES encryption. • Reduced equipment and fiber at the central office
  11. 11. • GPON adopts Wavelength Division Multiplexing (WDM) technology, facilitating bi-direction communication over a single fiber. 1490nm 1310nm
  12. 12. • To separate upstream/downstream signals of multiple users over a single fiber • GPON adopts two multiplexing mechanisms: i. In downstream direction, data packets are transmitted in a broadcast manner; ii. In upstream direction, data packets are transmitted in a TDMA manner.
  13. 13. • Line rate. i. Downstream : 2.488 Gb/s ii. Upstream : 1.244 Gb/s. • Broadcast mode i. Continuous mode operation. ii. Traffic in the downstream is sent to/received by every ONU. • Issue i. Data confidentiality ii. AES-Advanced Encryption Standard used for link layer encryption.
  14. 14. • TDMA(Time Division Multiple Access) i. Burst mode operation. ii. The OLT controls which ONU gets access to the upstream at a particular moment in time. • Concerns i. Potential collision ii. Access granting. iii. Distance ranging.