FIBER DISTRIBUTED DATA INTERFACE (FDDI) ADNAN MASOOD ECE DEPT EMAIL: AM98@DREXEL.EDU

INTRODUCTION SHARED MEDIA NETWORK LIKE ETHERNET (IEEE 802.3) & IBM TOKEN RING (IEEE 802.5) 100 Mbps SPEED RUNS ON OPTICAL FIBER AMERICAN NATIONAL STANDARDS INSTITUTE (ANSI) STANDARD

SEQUENCE OF PRESENTATION INTRODUCTION TIMELINE FOR DEVELOPMENT OF FDDI FDDI BASIC PRINCIPLE FDDI PHYSICAL PROPERTIES FDDI ARCHITECTURAL MODEL FDDI - II BENEFITS & LIMITATIONS APPLICATIONS COMPARISON WITH OTHER NETWORKS MARCH 6, 2003 FDDI

TIMELINE FOR FDDI PROJECT INITIATED IN OCTOBER 1982 BY JAMES HAMSTRA AT SPERRY (NOW UNISYS) TWO PROPOSALS FOR MEDIA ACCESS CONTROL (MAC) & PHYSICAL (PHY) LAYERS SUBMITTED IN JUNE 1983 FDDI MAC BECAME AN ANSI STANDARD IN LATE 1986 FDDI PHY WON ANSI STANDARDIZATION IN 1988 FDDI - II PROPOSAL WAS MADE IN EARLY 1986 FIRST PUBLIC DEMONSTRATIONS AT ADVANCED MICRO DEVICES (AMD) IN 1989 MARCH 6, 2003 FDDI

FDDI BASIC PRINCIPLE TOKEN RING NETWORK LIKE IEEE 802.5 TOKEN: A SPECIAL SEQUENCE OF BITS TOKEN CIRCULATES AROUND THE RING A STATION REMOVES THE TOKEN FROM RING BEFORE TRANSMISSION AFTER TRANSMISSION, THE STATION RETURNS THE TOKEN TO THE RING COLLISIONS ARE PREVENTED AS THERE IS ONLY ONE TOKEN IN THE RING MARCH 6, 2003 FDDI

TOKEN RING NETWORK MARCH 6, 2003 FDDI

FDDI BASIC PRINCIPLE TOKEN RING NETWORK LIKE IEEE 802.5 TOKEN: A SPECIAL SEQUENCE OF BITS TOKEN CIRCULATES AROUND THE RING A STATION REMOVES THE TOKEN FROM RING BEFORE TRANSMISSION AFTER TRANSMISSION, THE STATION RETURNS THE TOKEN TO THE RING COLLISIONS ARE PREVENTED AS THERE IS ONLY ONE TOKEN IN THE RING MARCH 6, 2003 FDDI

FDDI PHYSICAL PROPERTIES DUAL-COUNTER-ROTATING TOKEN RING ARCHITECTURE ONE RING IS PRIMARY AND THE OTHER SECONDARY UP TO 500 STATIONS WITH A MAXIMUM DISTANCE OF 2 KM BETWEEN ANY PAIR OF STATIONS FOR MULTIMODE FIBER WITH SINGLE-MODE FIBER THE DISTANCE CAN BE UP TO 40 KM MAXIMUM RING LENGTH IS 100 KM (TOTAL FIBER LENGTH IS 200 KM FOR TWO RINGS) USES 4B/5B ENCODING MARCH 6, 2003 FDDI

FDDI DUAL RINGS FDDI DUAL RING ARCHITECTURE MARCH 6, 2003 FDDI

OPERATION ON FAILURE OF THE PRIMARY RING MARCH 6, 2003 FDDI

FDDI ARCHITECTURAL MODEL ACCORDING TO THE OSI-RM, FDDI SPECIFIES LAYER 1 (PHYSICAL LAYER) AND PART OF LAYER 2 (DATA LINK CONTROL LAYER) THE PHYSICAL LAYER HANDLES THE TRANSMISSION OF RAW BITS OVER A COMMUNICATIONS LINK THE DATA LINK CONTROL (DLC) LAYER IS RESPONSIBLE FOR MAINTAINING THE INTEGRITY OF INFORMATION EXCHANGED BETWEEN TWO POINTS MARCH 6, 2003 FDDI

RELATIONSHIP BETWEEN FDDI AND OSI-RM MARCH 6, 2003 FDDI

THE PMD LAYER PMD LAYER DEFINES THE TYPE OF MEDIA INTERCONNECTION AND ITS CHARACTERISTICS SUCH AS TRANSMITTER POWER, FREQUENCIES, RECEIVER SENSITIVITIES, BIT ERROR RATES (BER), OPTICAL COMPONENTS ETC. PMD-MMF: MULTIMODE (62.5 MICRON CORE DIAMETER) FIBER PMD-SMF: SINGLE-MODE (8-10 MICRON CORE DIAMETER) FIBER ALSO DEFINES STP, UTP AS MEDIA AND FDDI ON SONET MARCH 6, 2003 FDDI

THE PHY LAYER PROVIDES THE MEDIA INDEPENDENT FUNCTIONS ASSOCIATED WITH THE OSI PHYSICAL LAYER RECEPTION: DECODES THE RECEIVED BIT STREAM FROM PMD INTO A SYMBOL STREAM FOR USE BY THE MAC LAYER TRANSMISSION: ENCODES THE DATA AND CONTROL SYMBOLS PROVIDED BY MAC USING 4B/5B ENCODING FOR THE PMD LAYER ALSO PROVIDES SMT THE SERVICES REQUIRED FOR THE ESTABLISHMENT AND MAINTENANCE OF THE FDDI RING (BY CONTINUOUSLY LISTENING TO THE INCOMING SIGNAL) MARCH 6, 2003 FDDI

THE MAC LAYER PROVIDES FAIR & DETERMINISTIC ACCESS FAIR: NO NODE HAS ADVANTAGE OVER ANOTHER IN ACCESSING THE MEDIUM DETERMINISTIC: UNDER ERROR-FREE CONDITIONS, THE TIME A NODE HAS TO WAIT TO ACCESS THE MEDIUM CAN BE PREDICTED MEDIUM ACCESS IS CONTROLLED BY A TOKEN TOKEN PERMITS THE NODE THAT RECEIVES IT TO TRANSMIT FRAMES THE MAC LAYER OF THE NODE THAT GENERATED THE FRAME IS RESPONSIBLE FOR REMOVING THE TOKEN MARCH 6, 2003 FDDI

THE SMT LAYER A SOPHISTICATED, BUILT-IN NETWORK MONITORING AND MANAGEMENT CAPABILITY SMT IS NOT AN OSI-RM SPECIFICATION MAKING USE OF THE SERVICES PROVIDED BY PMD, PHY, AND MAC, IT CARRIES OUT MANY FUNCTIONS SUCH AS NODE INITIALIZATION, BYPASSING FAULTY NODES, COORDINATION OF NODE INSERTION AND REMOVAL, FAULT ISOLATION AND RECOVERY SMT IS MOST COMMONLY IMPLEMENTED AS A SOFTWARE PROCESS RUNNING ON THE FDDI DEVICE MARCH 6, 2003 FDDI

FDDI - II ENHANCED FDDI THAT HANDLES DATA, VOICE, AND VIDEO SAME FEATURES AS BASIC FDDI (FDDI - I), INCLUDING MAXIMUM NUMBER OF MODES, 100 MBPS DATA TRANSFER BIT RATE, AND THE DUAL RING DEFINES THE PHYSICAL LAYER AND THE LOWER HALF OF THE DATA LINK LAYER SIMILAR TO FDDI-I FDDI-I SUPPORTS ONLY PACKET MODE (SYNCHRONOUS AND ASYNCHRONOUS) TRAFFIC, FDDI-II SUPPORTS BOTH PACKET DATA AS WELL AS ISOCHRONOUS DATA TRAFFIC (IN FDDI ISOCHRONOUS INDICATES A CLASS OF TRAFFIC FOR VOICE AND VIDEO THE SIMULTANEOUS SUPPORT OF BOTH PACKET AND ISOCHRONOUS TRAFFIC IS CALLED THE HYBRID MODE OF OPERATION MARCH 6, 2003 FDDI

FDDI-II STATION ARCHITECTURAL MODEL MARCH 6, 2003 FDDI

FDDI BENEFITS HIGH BANDWIDTH (10 TIMES MORE THAN ETHERNET) LARGER DISTANCES BETWEEN FDDI NODES BECAUSE OF VERY LOW ATTENUATION ( 0.3 DB/KM) IN FIBERS IMPROVED SIGNAL-TO-NOISE RATIO BECAUSE OF NO INTERFERENCE FROM EXTERNAL RADIO FREQUENCIES AND ELECTROMAGNETIC NOISE BER TYPICAL OF FIBER-OPTIC SYSTEMS (10^-11) IS SUBSTANTIALLY BETTER THAN THAT IN COPPER (10^-5) AND MICROWAVE SYSTEMS (10^-7) VERY DIFFICULT TO TAP SIGNALS FORM A FIBER CABLE MARCH 6, 2003 FDDI

COMPARISON OF TRANSMISSION MEDIA MARCH 6, 2003 FDDI

FDDI LIMITATIONS HIGH COST OF OPTICAL COMPONENTS REQUIRED FOR TRANSMISSION/RECEPTION OF SIGNALS (ESPECIALLY FOR SINGLE MODE FIBER NETWORKS) MORE COMPLEX TO IMPLEMENT THAN EXISTING LOW SPEED LAN TECHNOLOGIES SUCH AS IEEE 802.3 AND IEEE 802.5 MARCH 6, 2003 FDDI

APPLICATIONS OF FDDI OFFICE AUTOMATION AT THE DESKTOP BACKBONES FOR FACTORY AUTOMATION BACKEND DATA CENTER APPLICATIONS CAMPUS LAN INTERCONNECTION INTERCAMPUS BACKBONES OR METROPOLITAN AREA NETWORKS (MANs) INTERCONNECTION OF PRIVATE BRANCH EXCHANGES (PBXS) WORKGROUP AND DEPARTMENTAL LANS INTEGRATED TRANSPORT FOR MULTIMEDIA APPLICATIONS MARCH 6, 2003 FDDI

A FDDI BACKBONE NETWORK EXAMPLE MARCH 6, 2003 FDDI

COMPARISON WITH OTHER NETWORKS FEATURES FDDI ETHERNET TOKEN RING TRANSMISSION RATE 125 MBAUD 20 MBAUD 8 & 32 MBAUD DATA RATE 100 MBPS 10 MBPS 4 & 16 MBPS SIGNAL ENCODING 4B/5B (80% EFFICIENT) MANCHESTER (50% EFFICIENT) DIFFERENTIAL MANCHESTER (50% EFFICIENT) MAXIMUM COVERAGE 100 KM 2.5 KM CONFIGURATION DEPENDENT MAXIMUM NODES 500 1024 250 MAXIMUM DISTANCE BETWEEN NODES 2 KM (MULTIMODE FIBER) 40 KM (SINGLE-MODE FIBER) 300 M (RECOMMENDED 100 M) MARCH 6, 2003 FDDI