ethernet standards
Download
Skip this Video
Download Presentation
Ethernet Standards

Loading in 2 Seconds...

play fullscreen
1 / 34

Ethernet Standards - PowerPoint PPT Presentation


  • 115 Views
  • Uploaded on

Ethernet Standards. Ethernet concepts origin DIX consortium – 1979 10Mbps Ethernet 1 st Blue book – 1980 IEEE group takes over – Project 802 802.1 – High Level Interface –HLI – Focused on high level inter-network protocols & management 802.2 – Logic Link Control

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about ' Ethernet Standards' - shaina


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
ethernet standards
Ethernet Standards
  • Ethernet concepts origin
  • DIX consortium – 1979
  • 10Mbps Ethernet 1st Blue book – 1980
  • IEEE group takes over – Project 802
    • 802.1 – High Level Interface –HLI –
      • Focused on high level inter-network protocols & management
    • 802.2 – Logic Link Control
    • 802.3 – Data Link & Medium Access Control
      • DLMAC
ethernet standards1
Ethernet Standards
  • 1982 – DLMAC – 3 groups
    • 802.3 – CSMA/CD – driven by DIX
    • 802.4 – Token Bus – burroughs, concorde,
    • 802.5 – Token – Ring - IBM
  • 1982 – DIX & IEEE merges
    • 1st version of 802.3 Ethernet standard
ethernet standards2
Ethernet Standards
  • IEEE 802.3 – series of specifications for 10Mbps
    • Thick coaxial – thicknet – 10Base5
    • Thin coaxial – thinnet- cheapernet –10Base2
    • UTP XBaseT
    • Fibre XBaseF
    • Broadband version XBroad36
ethernet standards3
Ethernet Standards
  • Other specifications
    • 100 Mbs – fast Ethernet
    • 1000 Mbps – gigabit Ethernet
    • Switched Ethernet
    • Proposal for 100MBps – 1982
    • IEEE 802 focused on 1- 20 MBps
    • ANSI took up 100 Mbps - led to FDDI
ethernet popularity
Ethernet Popularity
  • Low network management requirements
  • Open standards
    • Reasonable prices
    • Easy to license
    • 1990 – 10Mpbs Ethernet on UTP
      • 10BASE-T – inexpensive twisted pair
      • Massive surge in Ethernet installations
ethernet popularity1
Ethernet Popularity
    • Coincides with distributed high-performance computing to the desktop
  • Result
    • Large networks – many systems
    • More network aware applications
    • Massive increase in BW needs
ethernet popularity2
Ethernet Popularity
  • Result
    • Need for higher bit rates – fast Ethernet (1995 – 100BaseT)
    • Shift in Ethernet shared access – to switched Ethernet
    • High bit rate interconnectivity requirement
      • Gigabit Ethernet 109 bits per second
    • (Ethernet frame format maintained)
network connection
Network Connection
  • Network Interface Card – NIC
  • Attachment Unit Interface – AUI
  • Medium Attachment Unit – MAU
  • PHY + MAC – HW
  • LLC - SW
network connection1
Network Connection
  • PLS resides in DTE
    • Data o/p
    • Data I/p
    • Carries Sense
    • Error Sense
  • MAC
    • Data output in NRZ format
network connection2
Network Connection
  • MAC
    • Data output in NRZ format
  • PLS Manchester encoding – differential
  • AUI cable – 3 different signal pairs
    • DO
    • DI
    • CI (control input)
network connection3
Network Connection
  • AUI cable – 3 different signal pairs
    • Max length 50m
    • 15 pin connectors
    • Female on the DTE side
    • Male on the MAU side
network connection4
Network Connection
  • MAU – Transceiver
    • Transmit data
    • Receive data
    • Loopback
    • Collision detection
    • SQE test
    • Jabber protection
bus technologies
Bus Technologies
  • 10BASE5 – Thicknet – coaxial
  • 10BASE2 – Thinnet, coaxial – cheapernet
  • 10BASE-T – Twisted Pair
10base5 thicknet
10BASE5 Thicknet
  • Early 80s standard
  • Tapped Bus topology – 50 ohm coax cable
  • Maximum 500 m segment length
  • 100 users per segment
  • Max 4 repeaters
10base5 thicknet1
10BASE5 Thicknet
  • Transceivers separated by 2.5m
  • AUI- NIC to transceiver max 50 m
10base2 thinnet
10BASE2 Thinnet
  • 1989 standard BNC ( British Navel Connector)
  • Less expensive cable – flexible – to the desktop
  • Max segment size 185m, max nodes 30
  • Max length with repeaters – 925 m
  • Min distance between MAU = 0.5m
10base t twisted pair
10BASE-T Twisted Pair
  • Uses standard voice grade telephone cable
  • 1990 – IEEE 802.3i UTP standard
  • 4 twisted pairs
  • Star topology – logically bus
  • Hub – repeater at the centre
    • Signal restoration
    • Repeated incoming signal in all output ports
10base t twisted pair1
10BASE-T Twisted Pair
  • Advantages of star
  • Cable distance 100m to repeater
  • MAUs can be connected via AUI
  • MAU & AUI can be part of DTE or repeater
10base fl
10BASE-FL
  • Runs over 2 strands of single/multimode fibre
  • Fibre distance between MAU – 2000m
  • Point-to-point links
functions of a nic
Functions of a NIC
  • Create and Check CRC - error detection
  • Physical Addressing
  • Medium Access
  • Framing - encapsulate & decapsulate data
  • Encoding Data
  • Connection to Physical Medium
  • Transceiver - translates signal to medium specific signal
physical mac addresses
Physical MAC addresses
  • Unique Addresses
  • assigned by the IEEE
  • 48 bit address in two parts
    • First 24 bits specify the vendor (block number)
      • ex. AA-00-00 is a DEC NIC board
      • ex. 08-20-00 is SUN
    • Next 24 bits are a unique serial number
mac addressing
MAC addressing
  • Static
    • Most common
    • Vendor guaranteed uniqueness
  • Configurable
    • SW assigned MAC address
  • Dynamic
    • Random pick and check for uniqueness
types of addresses
Types of addresses
  • Broadcast
  • Multicast
  • Unicast
broadcast addresses
Broadcast addresses
  • A MAC address of all one’s
  • All NIC’s on a network accept broadcast addressed messages
multicast addresses
Multicast addresses
  • A specific MAC address that only certain NIC are programmed to accept
    • the first bit of the destination address is set to 1
unicast addresses
Unicast addresses
  • A unique MAC address assigned to each NIC which is used to send messages to that specific host.
    • the first bit of the destination address is set to 0
ethernet operation
Ethernet Operation
  • Broadcast/half duplex network
    • On a bus topology
  • Listen first then transmit if clear
  • What to do if you collide
    • Backoff and try again
csma cd
CSMA/CD
  • LAN transmissions operate on the idea of a bit period
  • For 10baseT this is 100ns (10,000,000 bits/sec)
  • 3 times to keep track of
    • Slot time
    • Interframe gap
    • Jam period
timings
Timings
  • Slot time – min time transmitter needs to access media to transmit smallest frame
    • All nodes must listen for 1 slot time before transmitting
    • 512 bit periods or 51.2 µsec
  • Interframe Gap (dead time) – space between transmissions of 96 bit periods or 9.6 µsec
timings1
Timings
  • On collision
  • All stations involved stop transmitting and transmit 32 bit time (3.2 µsec) jam signal
  • All attached stations hear the jam signal
  • Back-off algorithm used to determine when another attempt will be made
    • This is done up to 16 times
ethernet operations
Ethernet Operations
  • Min frame size: 64 bytes (72 counting preamble and SFD)
  • 64 bytes incl CRC, control, addresses and data fields (64 x 8 x 100ns = 51.2 µsec)
  • Max size is 1526 bytes
ad