1. FDDI Fiber Distributed Data Interface By Ya’kob, Aidid & Fikri

2. Introduction The best before Fast Ethernet & Gigabit Ethernet Product of American National Standards Institute Specifies a 100mbps token-passing, dual- ring LAN using fiber optic cable. Used as high-speed backbone technology before this. CDDI is another slower version.

3. Traffic on this dual ring architecture flows opposite direction ◦ One is primary & one is secondary ◦ Uses primary ring during normal operation & the secondary is idle. Secondary is ready for backup. ◦ Purpose : provide superior reliability and robustness

4. FDDI is a standard for data transmission in a LAN that can extend in range up to 200km. FDDI protocol is based on the token ring protocol Supports thousands of users. Fiber optic medium Dual-attach FDDI Board

5. A Station may send as many frames as it can within its task access period, with the proviso that real-time data be sent 1 st Two type of data frames : ◦ 1. Synchronous (S-frames) : information is real times ◦ 2. Asynchronus (A-frames) : information that is not real-times Each station that captures the token is required to send S-frames first. Any remaining time may the be used to send A-frames. Access Method : Token Passing

6. Adressing FDDI uses a six-byte address, which is imprinted on the NIC card similar to Ethernet addresses. Data Rate FDDI supports data rates up to 100mbps

7. Implementation: Dual Ring