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© 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential Presentation_ID 1
Chapter 4: Network Access
Introduction to Networks
Presentation_ID 2 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
Chapter 4 4.1 Physical Layer Protocols 4.2 Network Media 4.3 Data Link Layer Protocols 4.4 Media Access Control 4.5 Summary
Presentation_ID 3 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
Chapter 4: Objectives
Students will be able to:
Explain how physical layer protocols and services support communications across data networks.
Build a simple network using the appropriate.
Explain the role of the data link layer in supporting communications across data networks.
Compare media access control techniques and logical topologies used in networks.
4.0.1.1
Presentation_ID 4 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
Getting it Connected
Connecting to the Network
4.1.1.1
Do buttons on 4.1.1.1
Presentation_ID 5 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
Getting it Connected
Connecting to the Network
4.1.1.1
Presentation_ID 6 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
Getting it Connected
Network Interface Cards
Connecting to the Wireless LAN with a Range Extender
4.1.1.2
Presentation_ID 7 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
Purpose of the Physical Layer
The Physical Layer
4.1.2.1
Presentation_ID 8 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
Purpose of the Physical Layer
Physical Layer Media
4.1.2.2
Presentation_ID 9 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
Purpose of the Physical Layer
Physical Layer Standards
Standard organization Networking Standards
ISO • ISO 8877: Officially adopted the RJ connectors (e.g., RJ-11, RJ-45) • ISO 11801: Network cabling standard similar to EIA/TIA 568.
EIA/TIA
• TIA-568-C: Telecommunications cabling standards, used by nearly all voice, video and data networks.
• TIA-569-B: Commercial Building Standards for Telecommunications Pathways and Spaces
• TIA-598-C: Fiber optic color coding • TIA-942: Telecommunications Infrastructure Standard for Data Centers
ANSI • 568-C: RJ-45 pinouts. Co-developed with EIA/TIA
ITU-T • G.992: ADSL
IEEE • 802.3: Ethernet • 802.11: Wireless LAN (WLAN) & Mesh (Wi-Fi certification) • 802.15: Bluetooth
4.1.2.3
Do buttons on 4.1.2.3
Presentation_ID 11 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
Fundamental Principles of Layer 1
Physical Layer Fundamental Principles
Media Physical Components
Frame Encoding Technique
Signalling Method
Copper cable
• UTP • Coaxial • Connectors • NICs • Ports • Interfaces
• Manchester Encoding • Non-Return to Zero (NRZ)
techniques • 4B/5B codes are used with
Multi-Level Transition Level 3 (MLT-3) signaling
• 8B/10B • PAM5
• Changes in the electromagnetic field
• Intensity of the electromagnetic field
• Phase of the electromagnetic wave
Fiber Optic cable
• Single-mode Fiber • Multimode Fiber • Connectors • NICs • Interfaces • Lasers and LEDs • Photoreceptors
• Pulses of light • Wavelength multiplexing using
different colors
• A pulse equals 1. • No pulse is 0.
Wireless media
• Access Points • NICs • Radio • Antennae
• DSSS (direct-sequence spread-spectrum)
• OFDM (orthogonal frequency division multiplexing)
• Radio waves
4.1.3.1 Do buttons on
4.1.3.1
Presentation_ID 12 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
Fundamental Principles of Layer 1
Bandwidth
4.1.3.2
Presentation_ID 13 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
Fundamental Principles of Layer 1
Throughput
4.1.3.3
Know the Difference:
• Bandwidth • Throughput • Goodput
Try: www.speedtest.net
One student Then all at once!
Presentation_ID 14 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
Fundamental Principles of Layer 1
Types of Physical Media
4.1.3.4
Presentation_ID 15 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
Fundamental Principles of Layer 1
4.1.3.5 Activity - Physical Layer Terminology
4.1.3.5
Do in Activities on both buttons
in class
Presentation_ID 16 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
Network Media
Copper Cabling
4.2.1
Presentation_ID 17 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
Copper Cabling
Characteristics of Copper Media
4.2.1.1
Do the animation on 4.2.1.1
Presentation_ID 18 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
Copper Cabling
Copper Media
Shielded Twisted Pair (STP) cable Unshielded Twisted Pair (UTP) cable
Coaxial cable 4.2.1.2
Know: UTP STP
Presentation_ID 19 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
Copper Cabling
Unshielded Twisted-Pair (UTP) Cable
4.2.1.3
Presentation_ID 20 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
Copper Cabling
Shielded Twisted-Pair (STP) Cable
Foil Shields
Braided or Foil Shield
4.2.1.4
Presentation_ID 21 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
Copper Cabling
Coaxial Cable
4.2.1.5
Presentation_ID 22 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
Copper Cabling
Cooper Media Safety
4.2.1.6
Presentation_ID 23 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
UTP Cabling
4.2.1.7 Activity - Copper Media Characteristics
4.2.1.7
Do activity 4.2.1.7 in class
Presentation_ID 24 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
UTP Cabling
Properties of UTP Cabling
4.2.2
Presentation_ID 25 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
UTP Cabling
Properties of UTP Cabling
4.2.2.1
Understand How Cancelation
Works to limit signal degradation
Each pair has a
Varying the number of twists
Presentation_ID 26 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
UTP Cabling
UTP Cabling Standards
4.2.2.2
Click on each cable on 4.2.2.2
Presentation_ID 27 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
UTP Cabling
UTP Connectors
4.2.2.3
Do buttons and watch video on 4.2.2.3
Note poorly made cable on button 3
Presentation_ID 28 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
UTP Cabling
Types of UTP Cable
4.2.2.4
Know straight-through
and crossover
Roll over is use to console to cisco
routers.
Presentation_ID 29 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
UTP Cabling
Testing UTP Cables
Test newly made cables for:
• Wire map • Cable length • Signal loss due
to attenuation • Crosstalk
4.2.2.5
Presentation_ID 30 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
UTP Cabling
4.2.2.6 Activity - Cable Pinouts
4.2.2.6
Do 4.2.2.6 in class
Presentation_ID 32 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
Fiber Optic Cabling
Properties of Fiber Optic Cabling
4.2.3.1
Fiber-optic cabling is now being used in four types of industry: • Enterprise Networks • FTTH and Access
Networks • Long-Haul Networks • Submarine
Networks
Presentation_ID 33 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
Fiber Optic Cabling
Fiber Media Cable Design
4.2.3.2
Click on the parts of the diagram on 4.2.3.2
Presentation_ID 34 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
Fiber Optic Cabling
Types of Fiber Media
4.2.3.3 Click on buttons on 4.2.3.3
Presentation_ID 35 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
Fiber Optic Cabling
Network Fiber Connectors
4.2.3.4 Click on buttons on 4.2.3.4
Presentation_ID 36 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
Fiber Optic Cabling
Network Fiber Connectors
4.2.3.4
TIA-598 standard which recommends the use of a • Yellow jacket for single-mode fiber cables • Orange (or aqua) for multimode fiber cables
Click on buttons on 4.2.3.4
Presentation_ID 37 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
Fiber Optic Cabling
Testing Fiber Cables
4.2.3.5
Presentation_ID 38 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
Fiber Optic Cabling
Fiber versus Copper Implementation issues Copper media Fibre-optic
Bandwidth supported 10 Mbps – 10 Gbps 10 Mbps – 100 Gbps
Distance Relatively short (1 – 100 meters)
Relatively High (1 – 100,000 meters)
Immunity to EMI and RFI Low High (Completely immune)
Immunity to electrical hazards Low High (Completely immune)
Media and connector costs Lowest Highest
Installation skills required Lowest Highest
Safety precautions Lowest Highest 4.2.3.6
Presentation_ID 39 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
Fiber Optic Cabling
4.2.3.7 Activity - Fiber Optics Terminology
4.2.3.5
Do Activity 4.2.3.7 in class
Presentation_ID 40 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
Wireless Media
Properties of Wireless Media
4.2.4.1
Wireless does have some areas of concern including: • Coverage area • Interference • Security
Presentation_ID 41 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
• IEEE 802.11 standards • Commonly referred to as Wi-Fi. • Uses CSMA/CA • Variations include:
• 802.11a: 54 Mbps, 5 GHz • 802.11b: 11 Mbps, 2.4 GHz • 802.11g: 54 Mbps, 2.4 GHz • 802.11n: 600 Mbps, 2.4 and 5 GHz • 802.11ac: 1 Gbps, 5 GHz • 802.11ad: 7 Gbps, 2.4 GHz, 5 GHz, and 60 GHz
• IEEE 802.15 standard • Supports speeds up to 3 Mbps • Provides device pairing over distances from 1 to
100 meters.
• IEEE 802.16 standard • Provides speeds up to 1 Gbps • Uses a point-to-multipoint topology to provide
wireless broadband access.
Wireless Media
Types of Wireless Media
4.2.4.2
Presentation_ID 42 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
Wireless Media
Wireless LAN
Cisco Linksys EA6500 802.11ac wireless router
4.2.4.3
Presentation_ID 43 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
Wireless Media
802.11 Wi-Fi Standards
Standard Maximum Speed Frequency Backwards
compatible
802.11a 54 Mbps 5 GHz No
802.11b 11 Mbps 2.4 GHz No
802.11g 54 Mbps 2.4 GHz 802.11b
802.11n 600 Mbps 2.4 GHz or 5 GHz 802.11b/g
802.11ac 1.3 Gbps (1300 Mbps)
2.4 GHz and 5.5 GHz 802.11b/g/n
802.11ad 7 Gbps (7000 Mbps)
2.4 GHz, 5 GHz and 60 GHz 802.11b/g/n/ac
4.2.4.4
Presentation_ID 44 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
Wireless Media 4.2.4.5 Packet Tracer - Connecting a Wired and Wireless LAN 4.2.4.6 Lab - Viewing Wired and Wireless NIC Information
4.2.4.5 - 4.2.4.6
Homework:
Do Packet Tracer 4.2.4.5
Presentation_ID 45 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
Purpose of the Data Link Layer
The Data Link Layer
4.3.1.1
Presentation_ID 46 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
Purpose of the Data Link Layer
Data Link Sublayers
Network
Data Link
LLC Sublayer
MAC Sublayer
Physical
802.
3
Eth
erne
t
802.
11
Wi-F
i
802.
15
Blu
etoo
th
4.3.1.2
The data link layer is actually divided into two sublayers: • Logical Link
Control (LLC) • Media Access
Control (MAC)
Presentation_ID 47 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
Purpose of the Data Link Layer
Media Access Control
4.3.1.3
Do Animation on 4.3.1.3
Presentation_ID 48 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
Purpose of the Data Link Layer
Providing Access to Media
4.3.1.4
Do Animation on 4.3.1.4
Presentation_ID 49 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
Data Link Layer
Layer 2 Frame Structure
4.3.2.1
Presentation_ID 50 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
Layer 2 Frame Structure
Creating a Frame
4.3.2.2
Presentation_ID 51 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
Layer 2 Frame Structure
4.3.2.3 Activity - Generic Frame Fields
4.3.2.3
Do the Activities 4.3.2.3 on both buttons
in class
Presentation_ID 52 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
Data Link Layer
Layer 2 Standards
4.3.3.3
Presentation_ID 53 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
Layer 2 Standards
Data Link Layer Standards Standard
organization Networking Standards
IEEE
• 802.2: Logical Link Control (LLC) • 802.3: Ethernet • 802.4: Token bus • 802.5: Token passing • 802.11: Wireless LAN (WLAN) & Mesh (Wi-Fi certification) • 802.15: Bluetooth • 802.16: WiMax
ITU-T • G.992: ADSL • G.8100 - G.8199: MPLS over Transport aspects • Q.921: ISDN • Q.922: Frame Relay
ISO • HDLC (High Level Data Link Control) • ISO 9314: FDDI Media Access Control (MAC)
ANSI • X3T9.5 and X3T12: Fiber Distributed Data Interface (FDDI)
4.3.3.1
Presentation_ID 54 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
Topologies 4.3.3.2 Activity - Data Link Layer Standards Organizations
4.3.3.2
Do the Activity 4.3.3.2 in class
Presentation_ID 55 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
Topologies
Controlling Access to the Media
4.4.1.1
Presentation_ID 56 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
Topologies
Physical and Logical Topologies
4.4.1.2
Do the Buttons on 4.4.1.2 in class
Presentation_ID 57 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
WAN Topologies
Common Physical WAN Topologies
4.4.2.1
Presentation_ID 58 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
WAN Topologies
Physical Point-to-Point Topology
4.4.2.2
Presentation_ID 59 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
WAN Topologies
Logical Point-to-Point Topology
4.4.2.3
Do the Buttons on 4.4.2.3 in class
Presentation_ID 60 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
WAN Topologies
Half and Full Duplex
4.4.2.4
Do the Buttons and animations on 4.4.2.5
in class
Presentation_ID 61 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
LAN Topologies
Physical LAN Topologies
4.4.3.1
Presentation_ID 62 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
LAN Topologies
Logical Topology for Shared Media
4.4.3.2
Do the Buttons on 4.4.3.2 in class
Presentation_ID 63 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
LAN Topologies
Contention-Based Access
Characteristics Contention-Based Technologies • Stations can transmit at any time • Collision exist • There are mechanisms to resolve
contention for the media
• CSMA/CD for 802.3 Ethernet networks • CSMA/CA for 802.11 wireless networks
4.4.3.3
Presentation_ID 64 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
LAN Topologies
Multi-Access Topology
4.4.3.4
Do the Animation on 4.4.3.4 in class
Presentation_ID 65 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
LAN Topologies
Controlled Access
Characteristics Controlled Access Technologies • Only one station can transmit at a time • Devices wishing to transmit must wait
their turn • No collisions • May use a token passing method
• Token Ring (IEEE 802.5) • Fiber Distributed Data Interface (FDDI)
4.4.3.5 Both are obsolete
Presentation_ID 66 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
LAN Topologies
Ring Topology
4.4.3.6
Do the Animation on 4.4.3.6 in class
Presentation_ID 67 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
LAN Topologies 4.4.3.7 Activity - Logical and Physical Topologies
4.4.3.7
Do the Activity on 4.4.3.7 in class
Presentation_ID 68 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
Data Link Frame
The Frame
4.4.4.1
Do the Buttons 4.4.4.1 in class
Presentation_ID 69 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
Data Link Frame
The Header
4.4.4.2
Click on parts of 4.4.4.2 in class
Presentation_ID 70 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
Data Link Frame
Layer 2 Address
4.4.4.3
Presentation_ID 71 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
Data Link Frame
The Trailer
4.4.4.4
Click on parts of 4.4.4.4 in class
Presentation_ID 72 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
Data Link Frame
LAN and WAN Frames
4.4.4.5
Do animation on 4.4.4.4 in class
Presentation_ID 73 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
Data Link Frame
Ethernet Frame
4.4.4.6
Minimum Frame length:
64 or 72? Depends on if you
count the Preamble
Presentation_ID 74 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
Data Link Frame
Point-to-Point Protocol Frame
4.4.4.7
Presentation_ID 75 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
Data Link Frame
802.11 Wireless Frame
4.4.4.8
Presentation_ID 76 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
Data Link Frame
4.4.4.9 Activity - Frame Fields
4.4.4.9
Do activities on all buttons on 4.4.4.9
In class
Presentation_ID 77 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential
Network Access
Summary • Physical Layer Protocols
• Network Media
• Data Link Layer Protocols
• Media Access Control
4.5.1.1 – 4.5.1.2
Presentation_ID 78 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Confidential