FIBER DISTRIBUTED DATA INTERFACE (FDDI) ADNAN MASOOD ECE DEPT

MARCH 6, 2003FDDI2 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

MARCH 6, 2003FDDI3 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, 2003FDDI4 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, 2003FDDI5 FDDI BASIC PRINCIPLE TOKEN RING NETWORK LIKE IEEE 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, 2003FDDI6 TOKEN RING NETWORK

MARCH 6, 2003FDDI7 FDDI BASIC PRINCIPLE TOKEN RING NETWORK LIKE IEEE 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, 2003FDDI8 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, 2003FDDI9 FDDI DUAL RINGS FDDI DUAL RING ARCHITECTURE

MARCH 6, 2003FDDI10 OPERATION ON FAILURE OF THE PRIMARY RING

MARCH 6, 2003FDDI11 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, 2003FDDI12 RELATIONSHIP BETWEEN FDDI AND OSI-RM

MARCH 6, 2003FDDI13 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, 2003FDDI14 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, 2003FDDI15 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, 2003FDDI16 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, 2003FDDI17 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, 2003FDDI18 FDDI-II STATION ARCHITECTURAL MODEL

MARCH 6, 2003FDDI19 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, 2003FDDI20 COMPARISON OF TRANSMISSION MEDIA

MARCH 6, 2003FDDI21 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 AND IEEE 802.5

MARCH 6, 2003FDDI22 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, 2003FDDI23 A FDDI BACKBONE NETWORK EXAMPLE

MARCH 6, 2003FDDI24 COMPARISON WITH OTHER NETWORKS FEATURESFDDIETHERNETTOKEN RING TRANSMISSION RATE 125 MBAUD20 MBAUD8 & 32 MBAUD DATA RATE100 MBPS10 MBPS4 & 16 MBPS SIGNAL ENCODING 4B/5B (80% EFFICIENT) MANCHESTER (50% EFFICIENT) DIFFERENTIAL MANCHESTER (50% EFFICIENT) MAXIMUM COVERAGE 100 KM2.5 KMCONFIGURATION DEPENDENT MAXIMUM NODES MAXIMUM DISTANCE BETWEEN NODES 2 KM (MULTIMODE FIBER) 40 KM (SINGLE- MODE FIBER) 2.5 KM300 M (RECOMMENDED 100 M)

MARCH 6, 2003FDDI25 REFERENCES SONU MIRCHANDANI & RAMAN KHANNA (EDITORS), FDDI TECHNOLOGY AND APPLICATIONS, CHAPTERS 1,2,3,6,13, JOHN WILEY & SONS, INC., 1992 AMIT SHAH & G. RAMAKRISHNAN, FDDI: A HIGH SPEED NETWORK, PTR PRENTICE HALL, 1994 BERNHARD ALBERT & ANURA P. JAYASUMANA, FDDI AND FDDI-II - ARCHITECTURE PROTOCOLS, AND PERFORMANCE, ARTECH HOUSE, 1994 LARRY L. PETERSON & BRUCE S. DAVIE, COMPUTER NETWORKS: A SYSTEMS APPROACH, MORGAN KAUFMANN, ITO_DOC/FDDI.HTM#XTOCID14HTTP:// ITO_DOC/FDDI.HTM#XTOCID14