1. 1

2. ARP
• Address Resolution Protocol
• ARP works by broadcasting packets to all hosts
attached to the LAN
• ARP packet contains IP address in which sender is
interested in communicating with hosts keep a list of
ARP responses in an ARP table
• ARP is propagated through Bridges/Switches but not
through Routers
2

3. 1.1 wants to send the data to 1.3
1.1 wants to send the data to 1.3
192.168.1.4
00-20-18-C0-07-74
ource MAC
Source IP
-18-C0-07-71 192.168.1.1
ination MAC Destination IP
-18-C0-07-73192.168.2.1
Segment
192.168.1.3
00-20-18-C0-07-73
192.168.1.1
00-20-18-C0-07-71
192.168.1.2
00-20-18-C0-07-72
3

4. Data Encapsulation & De-capsulation
192.168.1.1
00-20-18-C0-07-71
Application
Application
Data
Presentation
Presentation
Data
Session
Session
Data
Transport
Transport
TH
Data
Segment
Network
Network
Packet
NH Segment
Data Link
Data Link
Packet
DHFrameDT
Physical
Physical
Bits
4

5. Data Encapsulation & De-capsulation
192.168.1.1
00-20-18-C0-07-71
Application
Application
Data
Presentation
Presentation
Data
Session
Session
Data
Transport
Transport
TH
Data
Segment
Network
Network
Data Link
Data Link
Physical
Physical
5

6. Hub
• It is a Physical layer device (Layer 1)
• It is Dummy Device
• It works with 0’s and 1’s (Bits)
• It works with broadcasting
• It works with shared bandwidth
• It is has 1 Broadcast Domain and 1 Collision Domain
• Collisions are identified using Access Methods called
CSMA/CD and CSMA/CA
6

7. Broadcast Domain & Collision Domain
• Broadcast Domain
Set of all devices that receive broadcast frames
originating from any device within the set.
• Collision domain
In Ethernet, the network area within which frames that
have collided are propagated is called a collision
domain.
Repeaters and hubs propagate collisions, LAN switches,
bridges, and routers do not.
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8. Types of Hubs
• Active Hubs uses power supply and
regenerates the
data (i.e.) strengthens the
signals in case of disturbances.
• Passive Hubs doesn’t use power supply and it will not
not regenerates the data (i.e.) strengthens the signals in
case of disturbances. It is used only to share the physical
media
• Intelligent Hubs are sometimes called as smart hubs.
These devices basically function as active hubs, but also
include a microprocessor chip and diagnostic capabilities
and are useful in troubleshooting situations.
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9. Switch
• It is Datalink layer device (Layer 2)
• Its is An Intelligent device
• It works with Physical addresses (i.e. MAC addresses)
• It works with fixed bandwidth
• It works with Flooding and Unicast
• It has 1 Broadcast domain and Number of Collision
domains depends upon the number of ports.
• It maintains a MAC address table
9

10. Types of Switches
• Manageable switches
On a Manageable switch an IP address can be assigned
and configurations can be made. It has a console port .
• Unmanageable switches
On an Unmanageable switch configurations cannot be
made, an IP address cannot be assigned as there is no
console port.
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