Transcript Chapter 4 - Network Access
Chapter 4: Network Access
Introduction to Networks
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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 doda © 2008 Cisco Systems, Inc. All rights reserved.
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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
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Getting it Connected
Connecting to the Network
Do buttons on 4.1.1.1
4.1.1.1
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Getting it Connected
Connecting to the Network
4.1.1.1
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Getting it Connected
Network Interface Cards
Connecting to the Wireless LAN with a Range Extender
4.1.1.2
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Purpose of the Physical Layer
The Physical Layer
4.1.2.1
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Purpose of the Physical Layer
Physical Layer Media
4.1.2.2
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Purpose of the Physical Layer
Physical Layer Standards
Do buttons on 4.1.2.3
4.1.2.3
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Standard organization Networking Standards ISO EIA/TIA
• • • • • • ISO 8877: Officially adopted the RJ connectors (e.g., RJ-11, RJ-45) ISO 11801: Network cabling standard similar to EIA/TIA 568.
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 © 2008 Cisco Systems, Inc. All rights reserved.
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Purpose of the Physical Layer
4.1.2.4 Lab - Identifying Network Devices and Cabling Do lab 4.1.2.4
For a grade 4.1.2.4
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Fundamental Principles of Layer 1
Physical Layer Fundamental Principles
4.1.3.1
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Media Copper cable Physical Components
• UTP • Coaxial • Connectors • NICs • Ports • Interfaces
Fiber Optic cable Wireless media
• Single-mode Fiber • Multimode Fiber • Connectors • NICs • Interfaces • Lasers and LEDs • Photoreceptors • Access Points • NICs • Radio • Antennae
Frame Encoding Technique
• 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 • Pulses of light • Wavelength multiplexing using different colors • DSSS (direct-sequence spread spectrum) • OFDM (orthogonal frequency division multiplexing) • Radio waves © 2008 Cisco Systems, Inc. All rights reserved.
Signalling Method
• Changes in the electromagnetic field • Intensity of the electromagnetic field • Phase of the electromagnetic wave • A pulse equals 1.
• No pulse is 0. Do buttons on 4.1.3.1
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Fundamental Principles of Layer 1
Bandwidth
4.1.3.2
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Fundamental Principles of Layer 1
Throughput
4.1.3.3
Presentation_ID Know the Difference: • Bandwidth • Throughput • Goodput Try: www.speedtest.net
One student Then all at once!
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Fundamental Principles of Layer 1
Types of Physical Media
4.1.3.4
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Fundamental Principles of Layer 1
4.1.3.5 Activity - Physical Layer Terminology
Do in Activities on both buttons in class 4.1.3.5
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Network Media
Copper Cabling
4.2.1
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Copper Cabling
Characteristics of Copper Media
Do the animation on 4.2.1.1
4.2.1.1
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Copper Cabling
Copper Media
Unshielded Twisted Pair (UTP) cable Shielded Twisted Pair (STP) cable Know: UTP STP 4.2.1.2
Presentation_ID Coaxial cable © 2008 Cisco Systems, Inc. All rights reserved.
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Copper Cabling
Unshielded Twisted-Pair (UTP) Cable
4.2.1.3
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Copper Cabling
Shielded Twisted-Pair (STP) Cable
Braided or Foil Shield Foil Shields
4.2.1.4
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Copper Cabling
Coaxial Cable
4.2.1.5
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Copper Cabling
Cooper Media Safety
4.2.1.6
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UTP Cabling
4.2.1.7 Activity - Copper Media Characteristics
Do activity 4.2.1.7 in class 4.2.1.7
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UTP Cabling
Properties of UTP Cabling
4.2.2
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UTP Cabling
Properties of UTP Cabling
Understand How Cancelation Works to limit signal degradation Each pair has a Varying the number of twists 4.2.2.1
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UTP Cabling
UTP Cabling Standards
4.2.2.2
Presentation_ID Click on each cable on 4.2.2.2
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UTP Cabling
UTP Connectors
4.2.2.3
Presentation_ID Do buttons and watch video on 4.2.2.3
Note poorly made cable on button 3 © 2008 Cisco Systems, Inc. All rights reserved.
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UTP Cabling
Types of UTP Cable
4.2.2.4
Presentation_ID Know straight-through and crossover Roll over is use to console to cisco routers.
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UTP Cabling
Testing UTP Cables
4.2.2.5
Presentation_ID Test newly made cables for: • Wire map • Cable length • Signal loss due to attenuation • Crosstalk © 2008 Cisco Systems, Inc. All rights reserved.
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UTP Cabling
4.2.2.6 Activity - Cable Pinouts
4.2.2.6
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UTP Cabling
4.2.2.7 Lab - Building an Ethernet Crossover Cable 4.2.2.7
Presentation_ID Do 4.2.2.7 for a lab grade © 2008 Cisco Systems, Inc. All rights reserved.
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Fiber Optic Cabling
Properties of Fiber Optic Cabling
Fiber-optic cabling is now being used in four types of industry: • Enterprise Networks • FTTH and Access Networks • Long-Haul Networks • Submarine Networks 4.2.3.1
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Fiber Optic Cabling
Fiber Media Cable Design
4.2.3.2
Presentation_ID Click on the parts of the diagram on 4.2.3.2
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Fiber Optic Cabling
Types of Fiber Media
4.2.3.3
Presentation_ID Click on buttons on 4.2.3.3
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Fiber Optic Cabling
Network Fiber Connectors
4.2.3.4
Presentation_ID Click on buttons on 4.2.3.4
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Fiber Optic Cabling
Network Fiber Connectors
TIA-598 standard which recommends the use of a • • Yellow jacket for single-mode fiber cables Orange (or aqua) for multimode fiber cables 4.2.3.4
Presentation_ID Click on buttons on 4.2.3.4
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Fiber Optic Cabling
Testing Fiber Cables
4.2.3.5
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Fiber Optic Cabling
Fiber versus Copper
Implementation issues
Bandwidth supported Distance Immunity to EMI and RFI 4.2.3.6
Presentation_ID Immunity to electrical hazards Media and connector costs Installation skills required Safety precautions
Copper media
10 Mbps – 10 Gbps Relatively short (1 – 100 meters) Low Low Lowest Lowest Lowest © 2008 Cisco Systems, Inc. All rights reserved.
Fibre-optic
10 Mbps – 100 Gbps Relatively High (1 – 100,000 meters) High (Completely immune) High (Completely immune) Highest Highest Highest Cisco Confidential 38
Fiber Optic Cabling
4.2.3.7 Activity - Fiber Optics Terminology
4.2.3.5
Presentation_ID Do Activity 4.2.3.7 in class © 2008 Cisco Systems, Inc. All rights reserved.
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Wireless Media
Properties of Wireless Media
Wireless does have some areas of concern including: • Coverage area • Interference • Security 4.2.4.1
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Wireless Media
Types of Wireless Media
• 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.
4.2.4.2
Presentation_ID • IEEE 802.16 standard • Provides speeds up to 1 Gbps • Uses a point-to-multipoint topology to provide wireless broadband access.
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Wireless Media
Wireless LAN
4.2.4.3
Presentation_ID Cisco Linksys EA6500 802.11ac wireless router © 2008 Cisco Systems, Inc. All rights reserved.
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Wireless Media
802.11 Wi-Fi Standards
Standard
802.11a
802.11b
802.11g
802.11n
802.11ac
802.11ad
Maximum Speed
54 Mbps 11 Mbps 54 Mbps 600 Mbps 1.3 Gbps (1300 Mbps) 7 Gbps (7000 Mbps)
Frequency
5 GHz 2.4 GHz 2.4 GHz 2.4 GHz or 5 GHz 2.4 GHz and 5.5 GHz 2.4 GHz, 5 GHz and 60 GHz
Backwards compatible
No No 802.11b
802.11b/g 802.11b/g/n 802.11b/g/n/ac 4.2.4.4
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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 Do Packet Tracer 4.2.4.5 And Lab 4.2.4.6
For a lab grade 4.2.4.5 - 4.2.4.6
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Purpose of the Data Link Layer
The Data Link Layer
4.3.1.1
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Purpose of the Data Link Layer
Data Link Sublayers
Network Data Link LLC Sublayer MAC Sublayer Physical
4.3.1.2
Presentation_ID The data link layer is actually divided into two sublayers: • Logical Link Control (LLC) • Media Access Control (MAC) © 2008 Cisco Systems, Inc. All rights reserved.
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Purpose of the Data Link Layer
Media Access Control
4.3.1.3
Presentation_ID Do Animation on 4.3.1.3
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Purpose of the Data Link Layer
Providing Access to Media
4.3.1.4
Presentation_ID Do Animation on 4.3.1.4
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Data Link Layer
Layer 2 Frame Structure
4.3.2.1
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Layer 2 Frame Structure
Creating a Frame
4.3.2.2
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Layer 2 Frame Structure
4.3.2.3 Activity - Generic Frame Fields
4.3.2.3
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Data Link Layer
Layer 2 Standards
4.3.3.3
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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
4.3.3.1
Presentation_ID
ISO ANSI
• • • • G.992: ADSL G.8100 - G.8199: MPLS over Transport aspects Q.921: ISDN Q.922: Frame Relay • • HDLC (High Level Data Link Control) ISO 9314: FDDI Media Access Control (MAC) • X3T9.5 and X3T12: Fiber Distributed Data Interface (FDDI) © 2008 Cisco Systems, Inc. All rights reserved.
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Topologies
4.3.3.2 Activity - Data Link Layer Standards Organizations 4.3.3.2
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Topologies
Controlling Access to the Media
4.4.1.1
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Topologies
Physical and Logical Topologies
4.4.1.2
Presentation_ID Do the Buttons on 4.4.1.2
in class © 2008 Cisco Systems, Inc. All rights reserved.
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WAN Topologies
Common Physical WAN Topologies
4.4.2.1
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WAN Topologies
Physical Point-to-Point Topology
4.4.2.2
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WAN Topologies
Logical Point-to-Point Topology
4.4.2.3
Presentation_ID Do the Buttons on 4.4.2.3
in class © 2008 Cisco Systems, Inc. All rights reserved.
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WAN Topologies
Half and Full Duplex
4.4.2.4
Presentation_ID Do the Buttons and animations on 4.4.2.5
in class © 2008 Cisco Systems, Inc. All rights reserved.
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LAN Topologies
Physical LAN Topologies
4.4.3.1
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LAN Topologies
Logical Topology for Shared Media
4.4.3.2
Presentation_ID Do the Buttons on 4.4.3.2 in class © 2008 Cisco Systems, Inc. All rights reserved.
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LAN Topologies
Contention-Based Access
• • •
Characteristics
Stations can transmit at any time Collision exist There are mechanisms to resolve contention for the media 4.4.3.3
Presentation_ID • •
Contention-Based Technologies
CSMA/CD for 802.3 Ethernet networks CSMA/CA for 802.11 wireless networks © 2008 Cisco Systems, Inc. All rights reserved.
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LAN Topologies
Multi-Access Topology
4.4.3.4
Presentation_ID Do the Animation on 4.4.3.4 in class © 2008 Cisco Systems, Inc. All rights reserved.
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LAN Topologies
Controlled Access
4.4.3.5
Presentation_ID • • • •
Characteristics
Only one station can transmit at a time Devices wishing to transmit must wait their turn No collisions May use a token passing method • •
Controlled Access Technologies
Token Ring (IEEE 802.5) Fiber Distributed Data Interface (FDDI) Both are obsolete © 2008 Cisco Systems, Inc. All rights reserved.
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LAN Topologies
Ring Topology
4.4.3.6
Presentation_ID Do the Animation on 4.4.3.6 in class © 2008 Cisco Systems, Inc. All rights reserved.
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LAN Topologies
4.4.3.7 Activity - Logical and Physical Topologies 4.4.3.7
Presentation_ID Do the Activity on 4.4.3.7 in class © 2008 Cisco Systems, Inc. All rights reserved.
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Data Link Frame
The Frame
Do the Buttons 4.4.4.1 in class 4.4.4.1
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Data Link Frame
The Header
4.4.4.2
Presentation_ID Click on parts of 4.4.4.2
in class © 2008 Cisco Systems, Inc. All rights reserved.
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Data Link Frame
Layer 2 Address
4.4.4.3
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Data Link Frame
The Trailer
4.4.4.4
Presentation_ID Click on parts of 4.4.4.4
in class © 2008 Cisco Systems, Inc. All rights reserved.
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Data Link Frame
LAN and WAN Frames
4.4.4.5
Presentation_ID Do animation on 4.4.4.4
in class © 2008 Cisco Systems, Inc. All rights reserved.
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Data Link Frame
Ethernet Frame
4.4.4.6
Presentation_ID Minimum Frame length: 64 or 72?
Depends on if you count the Preamble © 2008 Cisco Systems, Inc. All rights reserved.
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Data Link Frame
Point-to-Point Protocol Frame
4.4.4.7
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Data Link Frame
802.11 Wireless Frame
4.4.4.8
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Data Link Frame
4.4.4.9 Activity - Frame Fields
Do activities on all buttons on 4.4.4.9
In class 4.4.4.9
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Network Access
Summary
• Physical Layer Protocols • Network Media • Data Link Layer Protocols • Media Access Control 4.5.1.1 – 4.5.1.2
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