Remerciez-le!

Remerciez @Admin pour avoir partagé cet document gratuitement, de la manière la plus simple, en partageant sur les réseaux sociaux.

Spécialisation Télécoms Ethernet Mérilhou Vincent Saadi Bessa COMPARAISON ETHER

Spécialisation Télécoms Ethernet Mérilhou Vincent Saadi Bessa COMPARAISON ETHERNET 10MBIT/S 100 MBIT/S 1 Spécialisation Télécoms Ethernet INTRODUCTION..................................................................................................................................................... I. NORME DE L’ETHERNET................................................................................................................................. 2 Spécialisation Télécoms Ethernet I.1 DÉFINITION....................................................................................................................................................... II. LE STANDARD 802.3.......................................................................................................................................... II.2. LE SUPPLÉMENT 802.3 A.............................................................................................................................. II.3. SUPPLÉMENT 802.3 B, OU 10BROAD36.................................................................................................... II.4. SUPPLÉMENTS 802.3 C & D......................................................................................................................... II.5. SUPPLÉMENT 802.3 E.................................................................................................................................... II.6. LE SUPPLÉMENT 802.3 G............................................................................................................................. II.7. SUPPLÉMENT 802.3 H................................................................................................................................... II.8. SUPPLÉMENT 802.3 I..................................................................................................................................... II.9. SUPPLÉMENT 802.3 J..................................................................................................................................... II.10. LE STANDARD 802.1 D................................................................................................................................. III. LE PROTOCOLE MAC.................................................................................................................................... III.1. PRINCIPE DE FONCTIONNEMENT DE CSMA/CD ............................................................................. III.1. TRANSMISSION D’UNE TRAME............................................................................................................... III.2. DÉTECTION DES COLLISIONS................................................................................................................. III.3. REPRISE APRÈS COLLISION.................................................................................................................... III.4. RÉCEPTION D’UNE TRAME..................................................................................................................... III.5. MODÈLE FONCTIONNEL DE LA COUCHE MAC................................................................................. III.6. SERVICE MAC............................................................................................................................................... III.7. LA PRIMITIVE MA_DATA.REQUEST...................................................................................................... III.8. LA PRIMITIVE MA_DATA.INDICATION................................................................................................. III.9. LA COUCHE PHYSIQUE............................................................................................................................. III.10. SOUS-COUCHE PLS.................................................................................................................................... III.11. INTERFACE AUI.......................................................................................................................................... III.12. FONCTIONS DE LA MAU.......................................................................................................................... III.13. SERVICE PHY.............................................................................................................................................. III.13.B. GÉNÉRATION ET EFFETS.................................................................................................................... IV. LA TRAME ........................................................................................................................................................ IV.1. LE PRÉAMBULE............................................................................................................................................ 3 Spécialisation Télécoms Ethernet IV.2. L’ADRESSAGE................................................................................................................................................ IV.3. LE CHAMP TYPE LONGUEUR................................................................................................................... IV.4. LES DONNÉES................................................................................................................................................ IV.5. LE PAD.............................................................................................................................................................. IV.6. LE FCS (FRAME CHECK SEQUENCE)..................................................................................................... IV.7. LE TEMPS INTER-TRAMES........................................................................................................................ IV.8. LES TRAMES ERRONÉES........................................................................................................................... IV.9. LE RUNT.......................................................................................................................................................... IV.10. LE JABBER.................................................................................................................................................... IV.11. LA TRAME DÉSALIGNÉE.......................................................................................................................... IV.12. LES RÉPÉTEURS ........................................................................................................................................ IV.13. LES TRANSCEIVERS.................................................................................................................................. IV.14. LES FAN OUT................................................................................................................................................ IV.15. LES HUBS....................................................................................................................................................... IV.16. COMMUTATEURS ETHERNET................................................................................................................ IV.17. SUPPORT À BASE DE PAIRES TORSADÉES......................................................................................... IV.18. SUPPORTS À BASE DE FIBRE OPTIQUE............................................................................................... V. LES SOLUTIONS HAUTS DÉBITS................................................................................................................. V.1. LES SOLUTIONS À 100MB/S......................................................................................................................... V.2. 100BASET.......................................................................................................................................................... V.3. LE PROTOCOLE DE COMMUNICATION.................................................................................................. V.4.TOPOLOGIE...................................................................................................................................................... V.5. SIGNALISATION ET CODAGE..................................................................................................................... V.6. CÂBLAGE.......................................................................................................................................................... V.7. 100BASE T4........................................................................................................................................................ V.8. 100BASE TX...................................................................................................................................................... V.9. 100BASE-FX...................................................................................................................................................... V.10. 100 VG ANYLAN............................................................................................................................................. V.10.1. LE PROTOCOLE DE COMMUNICATION............................................................................................. 4 Spécialisation Télécoms Ethernet V.10.2. TOPOLOGIE...........................................................................................................................................62 V.10.3. SIGNALISATION ET CODAGE............................................................................................................... V.10.4. LE CÂBLAGE............................................................................................................................................. V.11. COMPARAISON DES SOLUTIONS A 100 MB/S...................................................................................... V.11.1. LE PROTOCOLE D’ACCÈS..................................................................................................................... V.11.2. CÂBLAGE ET TOPOLOGIE..................................................................................................................... V.11.3. COMPARAISON TECHNIQUE................................................................................................................. V.11.4. LES SOLUTIONS ÉCONOMIQUES......................................................................................................... V.12. CONCLUSION................................................................................................................................................ VI. BIBLIOGRAPHIE............................................................................................................................................. VII. GLOSSAIRE...................................................................................................................................................... VIII. INDEX.............................................................................................................................................................. 5 Spécialisation Télécoms Ethernet INTRODUCTION History 6 Spécialisation Télécoms Ethernet The beginning was the ALOHA system in Hawaii. Later carrier sensing was added, and Xerox built a 2.94 Mbps CSMA/CD system to connect over 100 personal workstations on a 1-km cable. The system was called ethernet after the luminiferous ether, through which electromagnetic radiation was once thought to propagate. Today the term ether refers to any media which we want to transmit data over (a data channel). The Xerox ethernet was so successful that Xerox, DEC and Intel drew up a standard for a 10Mbps ethernet. This standard formed the basis for the IEEE 802.3 standard but there is a difference between the way the Media Access Control protocol formats the packets. Also the IEEE standard describes a whole family of 1-persistent CSMA/CD systems running at speeds from 1 to 10 Mbps on various (baseband/broadband) media. Many people incorrectly use ethernet to refer to any CSMA/CD protocol. There are two types of cable used in the ethernet system. We generally refer to these as thick and thin ethernet. Thick ethernet usually refer to as 10 Base 5 uses a 50 Ohms coaxial cable about the size of a garden hose usually of a yellow color. Markings are inserted every 2.5 meters to show where taps go. Vampire taps with drops are used. Therefor 10 Base 5 tells us that the system transmits data at 10 Mbps, is a baseband system, and the maximum length permitted is 500 meters. In contrast thin ethernet, sometimes referred to as cheapernet uses a thinner more flexible coaxial cable. It also uses industry standard BNC connectors to form T junctions rather than taps. Thin net is referred to as 10 Base 2 where the maximum length is 200 meters. The IEEE specs also spell out how many repeaters are permitted thereby setting a maximum limit for the entire length of the LAN. For both 10 Base 5 and 10 Base 2 we are permitted a maximum of four repeater. This would allow up to five 500 meter thick net segments for a total of 2.5 Km and 1Km for 10 Base 2. Another newer IEEE 802 spec is called 10 Base T where T stands for twisted pair. This system uses unshielded twisted pair wired into a hub. The max distance from any workstation to the hub is 100 meters. 10 Base T forms a physical star but is actually a logical bus. The hub can be passive, active or a combination. It is most cost effective and does not suffer the problems of a physical bus when a break occurs. Also a misbehaved worstation can be quickly isolated with an intelligent active hub and automatically disconnected. All 802.3 implementations, including ethernet, use straight manchester encoding. The presence of a transition in the middle of each bit makes it possible to synchronize the sender and receiver. At any instant the ether can be in one of three states : transmitting a 0 bit, transmitting a 1 bit or idle (0 volts). A high signal is +0.85V and a low transition is a -0.85V. The voltage difference, of course would be 1.7V. Depending on the needs of the company many configurations can be set up. A thick net can be set up as a backbone (or even a fiber). Bridges can be used (sometimes called selective repeaters) on various floors of a high rise. Unlike ordinary repeaters, which just pass through bits without examining them, bridges examine each frame and only forwards those that need to be forwarded. Bridges need to know the locations of all stations in order to know whether to forward or not copy a frame. This can be preprogrammed in to the bridge or the newer devices listen to the traffic and are able to determine the stations and their locations. This document defines the functional requirements and guidelines for the IEEE Project 802.3 of Local Area Networks. The functional requirements include the use, environment, functions of such networks. It also defines the functional requirements for interfaces and protocols. 7 Spécialisation Télécoms Ethernet Local Area Networks A Local Area Network (LAN) is a data communications system which allows a number of independent data devices to communicate with each other. A Local Area Network is distinguished from other types of data networks in that communications are normally confined to a moderately sized geographic area, such as a single building or a campus. This is in contrast to a Wide Area Network (WAN) that may interconnect facilities in different parts of a country or of the world. Interoperation with public switched networks is an optional capability. Local Area Networks are also distinguished by their use of packet mode communications and a common Data Link Layer interface. The physical communications channel of a LAN has a moderate to high data rate and a consistently low error rate. An Integrated Voice/Data Local Area Network (IVD LAN) allows a number of independent integrated voice/data devices to communicate with one another and with integrated voice/data devices on a MAN or a WAN backbone network. The IVD LAN supports voice, data, facsimile, and other types of digitally encoded information. An IVD LAN differs from traditional (non-IVD) LANs in its physical integration of these information types. The physical communications channel of an IVD LAN has a moderate to high data rate and a consistently low error rate. The IVD LAN provides access to Integrated Services Digital Network (ISDN) WANs, IEEE Project 802 MANs, and IEEE Project 802 LANs. Scope The goal of LAN is to facilitate compatibility and interoperability between equipments made by different manufacturers such that communications can take place between the equipments. To accomplish this, these standards provide specifications that establish common interfaces and protocols for Local Area Networks (including IVD LANs). The intent of these standards is to provide an architecture that permits the effective interconnection of moderate cost devices, and is in itself, a moderate cost network. For some networks, low cost alternatives may also be provided. Model Packet mode data communication in LANs shall be described in terms of, and designed to be in conformance with, layered services and protocols as defined by the ISO Standard entitled « Open Systems Interconnection - Basic Reference Model » (ISO 7498) [1]. In so far as packet mode data communication is concerned, the focus of IEEE Project 802.3 is on the lower two layers (data link and physical) of the reference model . Security Functional requirements LANs are vulnerable to a variety of security threats. To assure interoperability while providing security services, IEEE Project 802.3 shall provide options for : a) Secure data exchange for all IEEE Project 802 networks. b) Cryptographic key management and distribution. c) Security management to manage objects securely. In addition, guidelines shall be provided for : b) Use of particular cryptographic algorithms as examples of how to implement protocols. b) Philosophy of key distribution to address manual distribution aspects not included in the protocol. 8 Spécialisation Télécoms Ethernet NOTE : Cryptographic algorithms are not a subject for IEEE Project 802.3 standardization. I. Norme de l’Ethernet I.1 Définition Ce chapitre décrit succintement le système Ethernet. Afin d’avoir un aperçu de uploads/s1/ ethernet-10-amp-100-mbits.pdf