Report CopyRight/DMCA Form For : Ethernet Basics Albedo Telecom
If metro WDM or SDH rings are available it is possib le to take advantage of them by means solutions like Ethernet over dark wavelength or NG SDH ADM Giga Switch Giga Switch Switch or Router Customer LAN Switch or Router Customer LAN Switch or Router Customer LAN DWDM OADM OADM OADM Optical Network Switch or Customer LAN Router Giga Switch Ethernet over Dark Fibre Ethernet over Dark
Ethernet Basics,Ethernet A Success Story,2014 ALBEDO Telecom All rights reserved. Ethernet refers to a family of technologies initially designed for LAN that have some things in. Packet oriented and statistical multiplexing technology. Very efficient for data transport, MAC layer and frame formats common to all Ethernet. Connectionless requires a bridging procedure of constant address learning. Low cost scalable multiple transmission media,Distributed control plane. L2 VPNs Point and multipoint configurations,History and Evolution. Alohanet developed in the late 1960s at the university of Haway is the Ethernet predecessor It. 2014 ALBEDO Telecom All rights reserved, was designed to allow two or more radio stations to share the same medium without interfering. between them,Honolulu Kahului,HAWAIIAN ISLANDS,Pacific Ocean. In 1973 Robert Metcalfe and his Team in Xerox designed the first version of Ethernet Ethernet I. The new technology allowed communication of computers connected to a shared medium coaxial. In 1982 it was released the first Ethernet standard by a consortium formed by Digital Equipment. Company Intel and Xerox This standard was a success from the beginning. In 1985 the IEEE published the first release of the 802 3 standard based on Ethernet Since that. moment Ethernet has not stopped its evolution,Ethernet and the OSI Reference Model. 2014 ALBEDO Telecom All rights reserved,IEEE 802 2 802 2 Logical Link Control. 802 1 Bridging,802 1 Management,802 Architecture,IEEE 802 3ab. IEEE 802 3u,IEEE 802 3,Token Ring,OSI Layers LAN Standards IEEE Standards. The Open System Interconnection OSI reference model defines the architecture of a layered. communication system The layers defined by the OSI model are Physical data link network. transport session presentation application, Ethernet is compatible with the OSI model Specifically Ethernet defines the physical and data link. The data link layer is composed by two sublayers Media Access Control MAC and Logical Link. IEEE 802 1 for bridging is located at the data link layer and is shared between Ethernet and other. IEEE layer 2 technologies,MAC Addresses,2014 ALBEDO Telecom All rights reserved. 00 51 34 B1 34 86,14 50 04 D0 B7 FA 01 32 12 FA 1D 22. Vendor OUI,bit 1 24 25 48, OUI Organizationally Unique Identifier IEEE administrated code. Vendor Code administrated by the manufacturer, The MAC layer was defined for communication of adjacent Ethernet stations. Ethernet links are multipoint and therefore an addressing scheme is necessary to identify stations. connected to this link, In switched Ethernet MAC addresses are used for switching frames. 2014 ALBEDO Telecom All rights reserved,1 2 3 4 5 6 7 8 bytes 1 2 3 4 5 6 7 8 bytes. Preamble 0x55 7,Preamble 0x55 8,SDF 0xd5 1,Type 2 Length Type 2. LLC 46 1500,Data 46 1500,MAC FCS 4 MAC FCS 4, DIX Frame Ethernet II 1982 IEEE 802 3 Ethernet MAC Frame 1985. There are more than one accepted MAC framing The IEEE 802 3 frame is backwards compatible. with the older DIX frame, The most important difference between DIX and 802 3 framings is the way user data is encapsulated. In the DIX framing the contents type is given by the Type field in the 802 3 frame the contents is. identified by its length The type is specified by means the LLC encapsulation. Media Access Control,2014 ALBEDO Telecom All rights reserved. Deterministic MAC Non deterministic MAC, There are many MAC protocols The IEEE defines alternative MAC layers for other technologies like. Token Ring, MAC protocols are commonly classified in deterministic and non deterministic. The Ethernet MAC protocol is non deterministic with First Come First Server FCFS philosophy. 2014 ALBEDO Telecom All rights reserved,transmission. Collision Yes Send jam,detected signal,Collision Attempts. detected Attempts 1,delay Transmission Too many No Compute. ended attempts delay,Random Yes Yes,Transmission Too many Wait. Completed collisions 1 microsecond,2014 ALBEDO Telecom All rights reserved. 1st preamble 7th preamble,octet octet,Preamble SFD. The transmitter station sends 64 bits 8 bytes at the beginning of each frame that enables the receiver. to synchronize with the incoming data, The first 7 transmitted bytes are known as preamble the 8th byte is the Start of Frame Delimiter. This byte is useful for the receiver to recognize the beginning of the frame. The DIX version of the Ethernet frame doesn t have SFD and it has an 8 byte preamble. High bit rate Ethernet use to work in full duplex mode In this case Ethernet stations can operate in. synchronous mode and the preamble is not necessary However it is maintained for compatibility of. all frame formats,Ethernet Errors, Error jabber It is defined in the IEEE 802 3 as a transmission of at least 20000 or 50000 bits. 2014 ALBEDO Telecom All rights reserved, Long frame These kind of frames are defined to be frames longer than the maximum allowed size. 1518 VLAN labeled frames are not considered to be long frames even if they exceed this maximum. Short frame Short frames are shorter than the minimum allowed size with a valid FCS. Runt It designates frames shorter than the minimum allowed size usually collision fragments. Therefore runts have an invalid FCS, FCS Error This kind of errors happens when a frame with legal size is received with an invalid FCS. due to transmission errors or other reason, Alignment Error It happens when there is not an integer number of bytes in the frame Usually is at. the same time is registered an FCS error, Range Error This error is computed when the value of the length field does not match the actual size. of the data field The Out of Range error is registered when the value of the length field is too big to. Ghost This error designates energy noise found in the transmission media that appears to be a. frame without a valid FCS This kind of errors is usually related with cabling problems. Auto Negotiation,2014 ALBEDO Telecom All rights reserved. 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15,Auto Negotiation Base Page. S0 S1 S2 S3 S4 A0 A1 A2 A3 A4 A5 A6 A7 RF Ack NP,10 100 1000BASE T. Priority Resolution,Highest Next Page present,Selector Field. 1000BASE T full duplex Acknowledgement,1000BASE T 00001 IEEE 802 3. Remote Fault Indicator,100BASE T2 full duplex 00010 IEEE 802 9. 100BASE TX full duplex Reserved,00011 802 5,100BASE T2 Asymmetric PAUSE full duplex only. 100BASE T4 PAUSE full duplex only,100BASE TX,100BASE T4 Half Duplex. 10BASE T full duplex,10BASE T 100BASE TX Full Duplex. Lowest 100BASE TX Half Duplex,10BASE T Full Duplex. 10BASE T Half Duplex, Some of the many Ethernet versions can talk to each other by means of Auto negotiation. 1 Inform the far end on which Ethernet version and options have been implemented. 2 Acknowledge features that both stations share and reject those that are not shared. 3 Configure each station for highest level mode of operation that both can support. The 5 4 3 Rule, The 5 4 3 Rule limits the size of the broadcast domain in half duplex ethernet networks. 2014 ALBEDO Telecom All rights reserved,5 Cable segments. 4 Repeaters, 3 Populated segments this rule only counts for coaxial implementations. Repeater Repeater Repeater Repeater, The 5 4 3 rule and the minimum frame size prevents undetected collisions. 10 Gigabit Ethernet,2014 ALBEDO Telecom All rights reserved. Interface Fiber Wavelength Modal bandwidth Range,62 5 m MMF 1300 nm 500 MHz km 2 300 m. 62 5 m MMF 1300 nm 400 MHz km 2 240 m,10GBASE LX4,50 m MMF 1300 nm 500 MHz km 2 300 m. 10 m MMF 1300 nm 2 10 km,62 5 m MMF 850 nm 160 MHz km 2 26 m. 62 5 m MMF 850 nm 200 MHz km 2 33 m,10GBASE S 50 m MMF 850 nm 400 MHz km 2 66 m. 50 m MMF 850 nm 500 MHz km 2 82 m,50 m MMF 850 nm 2000 MHz km 2 300 m. 10GBASE L 8 10 m SMF 1310 nm 2 10 km,10GBASE E 8 10 m SMF 1550 nm 2 40 km. 10Gbit s Ethernet is specified in standard IEEE 802 3ae released in 2002 The new standard. makes Ethernet suitable for WAN applications for first time. 10GbE abandons half duplex operation mode with shared links It relies on IEEE 802 1 bridging for. operation in topologies beyond simple point to point. It also abandons copper transmission Only interfaces based on optical fiber are defined. Some interfaces like 10GBASE LX4 are specially designed for LAN applications using existing fibre. The 10GBASE W interfaces improves convergence and inter operability between TDM and Ethernet. technologies,Gigabit Ethernet applications for LAN. 2014 ALBEDO Telecom All rights reserved,Horizontal Cabling. In LAN the new Ethernet interfaces are used,where legacy Fast Ethernet interface has. become a bottleneck Some of these LAN,Horizontal Cabling applications are. Aggregation of multiple lower rate segments in,switch server links. High traffic between switches trunk links,Interconnection of servers in clusters of servers. Vertical Cabling,Horizontal Cabling,LAN extension between buildings in campus. applications or communication between remote,Two gigabit interfaces have been especially. Corporate Servers designed to reuse the installed LAN. infrastructure 1000BASE T and 10GBASE LX4,Router Switch.