3. Network Access

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

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Chapter 3:

Network Access

Introduction to Networks

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.

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Chapter 3

3.1 Physical Layer Protocols

3.2 Network Media

3.3 Data Link Layer Protocols

3.4 Media Access Control

3.5 Summary

Connecting to the Network

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Getting it Connected

Connecting to the Network

Network Interface Cards

Connecting to the Wireless LAN with a Range Extender

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Purpose of the Physical Layer

The Physical Layer

Physical Layer Media

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Purpose of the Physical Layer

Physical Layer Standards

Standard

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

Physical Layer Fundamental Principles

Media Physical Components Frame Encoding Technique Signalling Method

• 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

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Fundamental Principles of Layer 1

Bandwidth

Throughput

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Fundamental Principles of Layer 1

Types of Physical Media

Copper Cabling

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Copper Cabling

Characteristics of Copper Media

Copper Media

Shielded Twisted Pair (STP) cable Unshielded Twisted Pair (UTP) cable

Coaxial cable

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Copper Cabling

Unshielded Twisted-Pair (UTP) Cable

Shielded Twisted-Pair (STP) Cable

Foil Shields Braided or Foil Shield

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Copper Cabling

Coaxial Cable

Cooper Media Safety

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UTP Cabling

Properties of UTP Cabling

UTP Cabling Standards

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UTP Cabling

UTP Connectors

Types of UTP Cable

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UTP Cabling

Testing UTP Cables

Properties of Fiber Optic Cabling

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Fiber Optic Cabling

Fiber Media Cable Design

Types of Fiber Media

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Fiber Optic Cabling

Network Fiber Connectors

Testing Fiber Cables

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Fiber Optic Cabling

Fiber versus Copper

(1 – 100 meters)

Relatively High (1 – 100,000 meters)

(Completely immune)

(Completely immune)

Properties of Wireless Media

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Wireless LAN

Cisco Linksys EA6500 802.11ac wireless router

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The Data Link Layer

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Purpose of the Data Link Layer

Data Link Sublayers

Media Access Control

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Purpose of the Data Link Layer

Providing Access to Media

Layer 2 Frame Structure

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Layer 2 Frame Structure

Creating a Frame

Layer 2 Standards

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Layer 2 Standards

Data Link Layer Standards

ISO • HDLC (High Level Data Link Control)

• ISO 9314: FDDI Media Access Control (MAC)

ANSI • X3T9.5 and X3T12: Fiber Distributed Data Interface (FDDI)

Controlling Access to the Media

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Topologies

Physical and Logical Topologies

Common Physical WAN Topologies

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WAN Topologies

Physical Point-to-Point Topology

Logical Point-to-Point Topology

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WAN Topologies

Half and Full Duplex

Physical LAN Topologies

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LAN Topologies

Logical Topology for Shared Media

Contention-Based Access

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LAN Topologies

Multi-Access Topology

Controlled Access

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LAN Topologies

Ring Topology

The Frame

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Data Link Frame

The Header

Layer 2 Address

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Data Link Frame

The Trailer

LAN and WAN Frames

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Data Link Frame

Ethernet Frame

Point-to-Point Protocol Frame

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Data Link Frame

802.11 Wireless Frame

• Physical Layer Protocols

• Network Media

• Data Link Layer Protocols

• Media Access Control