CS14802 Lecture Note 22
CS14802 Lecture Note 22
Data Communications
Data Communications
Sang-Ha Kim
shkim@cnu.ac.kr
ChungNam National University
Department of Computer Engineering
2008.09.04
2
Part 2. Network
Part 2. Network
Layer
Layer
Chapter 19. Network Layer : Logical Addressing
Chapter 20. Network Layer : Internet Protocol
Chapter 21. Network Layer : Address Mapping,
Error Reporting, and Multicasting
Chapter 22. Network Layer : Delivery, Forwarding, and
Routing
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Objectives
The network layer is responsible for the source-to-destination delivery of a packet,
possibly across multiple networks (links).
Whereas the data link layer oversees the delivery of the packet between two
systems on the same network (links), the network layer ensures that each packet
gets from its point of origin to its final destination.
The network layer is responsible for the delivery of individual
packet from the source to the destination host.
The network layer adds a header that includes the logical addresses of the sender
and receiver to the packet coming from the upper layer.
If a packet travels through the Internet, we need this addressing system to help
distinguish the source and destination.
One of the functions of the network layer is to provide a routing mechanism.
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Chapter 22. Network Layer : Delivery,
Forwarding, and Routing
Reference:
B.A. Forouzan, Communication Networks, 4
th
ed., McGraw-Hill,
2007, chapter 22, pp. 647 - 700.
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Contents
22.1 Delivery
22.2 Forwarding
22.3 Unicast Routing Protocols
22.4 Multicast Routing Protocols
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