OSI Data Link Layer

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23 Οκτ 2013 (πριν από 3 χρόνια και 10 μήνες)

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© 2007 Cisco Sy stems, Inc. All rights reserv ed.

Cisco Public

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Version 4.0

OSI Data Link Layer

Network Fundamentals


Chapter 7

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© 2007 Cisco Sy stems, Inc. All rights reserv ed.

Cisco Public

OSI Reference Model


Layer 2

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© 2007 Cisco Sy stems, Inc. All rights reserv ed.

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What will we learn from chapter 7?



Their role
in data
transmission


Prepare
data for transmission on network
media


Media
access control
methods


Common
logical network
topologies


Encapsulating
packets into
frames


Layer
2 frame structure
-

generic fields


Frame
header and trailer
fields:

addressing


QoS

Type
of
protocol

Frame
Check
Sequence

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© 2007 Cisco Sy stems, Inc. All rights reserv ed.

Cisco Public

Data Link Layer


Accessing the Media

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© 2007 Cisco Sy stems, Inc. All rights reserv ed.

Cisco Public

Data Link Layer


Accessing the Media

Why
Data Link layer protocols
required
to control media access


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© 2007 Cisco Sy stems, Inc. All rights reserv ed.

Cisco Public

Data Link Layer


Accessing the Media

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© 2007 Cisco Sy stems, Inc. All rights reserv ed.

Cisco Public

Data Link Layer


Accessing the Media

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© 2007 Cisco Sy stems, Inc. All rights reserv ed.

Cisco Public

Data Link Layer


Accessing the Media

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© 2007 Cisco Sy stems, Inc. All rights reserv ed.

Cisco Public

Media Access Control Techniques

Controlling
access to the media

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© 2007 Cisco Sy stems, Inc. All rights reserv ed.

Cisco Public

Media Access Control Techniques

Two media
access control methods for shared media and
their
basic
characteristics

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© 2007 Cisco Sy stems, Inc. All rights reserv ed.

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Media Access Control Techniques

Full
Duplex and Half Duplex as it relates to Media Access Control for non
-
shared media

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© 2007 Cisco Sy stems, Inc. All rights reserv ed.

Cisco Public

Media Access Control Techniques

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© 2007 Cisco Sy stems, Inc. All rights reserv ed.

Cisco Public

Media Access Control Techniques

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© 2007 Cisco Sy stems, Inc. All rights reserv ed.

Cisco Public

Media Access Control Techniques

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© 2007 Cisco Sy stems, Inc. All rights reserv ed.

Cisco Public

Media Access Control Techniques

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© 2007 Cisco Sy stems, Inc. All rights reserv ed.

Cisco Public

Media Access Control Techniques

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© 2007 Cisco Sy stems, Inc. All rights reserv ed.

Cisco Public

Media Access Control Addressing and Framing Data

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© 2007 Cisco Sy stems, Inc. All rights reserv ed.

Cisco Public

Media Access Control Addressing and Framing Data

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© 2007 Cisco Sy stems, Inc. All rights reserv ed.

Cisco Public

Media Access Control Addressing and Framing Data

The role
of addressing in the Data Link layer
-

cases
where
addresses are needed


or not
needed

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© 2007 Cisco Sy stems, Inc. All rights reserv ed.

Cisco Public

Media Access Control Addressing and Framing Data

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© 2007 Cisco Sy stems, Inc. All rights reserv ed.

Cisco Public

What did I Learn from chapter 7?



Their role in data transmission


They prepare data for transmission on network media


Media access control methods


Common logical network topologies


Encapsulating packets into frames


Layer 2 frame structure
-

generic fields


Frame header and trailer fields:

addressing


QoS

Type of protocol

Frame Check Sequence

22

© 2007 Cisco Sy stems, Inc. All rights reserv ed.

Cisco Public

Data Link Layer


Next

OSI Physical Layer