4. asim.raheel@
uettaxila.edu.pk
CCN
Course Learning Outcomes (CLO’s)
Sr.
No.
Course Learning Outcome (CLO’s) Bloom’s
Learning
Level
1. Understand basic communication model and addresses used at different
layers for communication.
C2
2. Apply signaling techniques and error detection and correction algorithms
used in data communication and networks.
C3
3. Compare different types of flow control and random-access mechanisms
for efficient communication.
C4
4. Analyze different routing algorithms for reliable communication. C4
7. Networks in Daily Life
asim.raheel@
uettaxila.edu.pk
CCN
Nowadays Networks are important part of our everyday activities:
Business
Home
Government
Education
10. Aim of the Course
asim.raheel@
uettaxila.edu.pk
CCN
Aim of the course is to
Introduce you to the world of computer networks
Science behind running a network
Basic administration skills
15. Why not connect each node with
every other node ?
asim.raheel@
uettaxila.edu.pk
CCN
Number of computers that can be connected becomes very limited
Number of wires coming out of each node becomes unmanageable
Amount of physical hardware/devices required becomes very expensive
Solution: indirect connectivity using intermediate data forwarding nodes
26. What Goes Wrong in the Network?
asim.raheel@
uettaxila.edu.pk
CCN
Reliability at stake
Bit-level errors (electrical interference)
Packet-level errors (congestion)
distinction between lost and late packet
Link and node failures
Distinction between broken and flaky link
Distinction between failed and slow node
27. What Goes Undesirable in the
Network?
asim.raheel@
uettaxila.edu.pk
CCN
Required performance at stake
Messages are delayed
Messages are delivered out-of-order
Third parties eavesdrop
The challenge is to fill the gap between application expectations and hardware capabilities
34. Protocol
asim.raheel@
uettaxila.edu.pk
CCN
Protocols define format, order of messages sent and received among network entities, and
actions taken on message transmission, receipt.
Hi
Hi
Got the
time?
2:00
TCP connection
req.
TCP connection
reply.
<file>
Get http://gaia.cs.umass.edu/index.htm
time
Human
Protocol
Computer
Protocol
35. Key Elements of Protocol
asim.raheel@
uettaxila.edu.pk
CCN
Syntax
Semantics
Timing
37. Summary
asim.raheel@
uettaxila.edu.pk
CCN
Data Communication is transfer of data from one device to another
A DC system must transmit data to correct destination in an accurate and timely manner
Five components of a DC system are: message, sender, receiver, medium and protocol
Data flow: Simplex, Half Duplex, Full Duplex
Network Topologies: Mesh, Star, Bus, Ring, Hybrid
Network Categories: LAN, WAN
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