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L E S S O N P L A N #55 Per.
Name:
DATE: Wednesday March 2nd, 2011
CLASS: Networking
TOPIC: Repeaters and Bridges
AIM: What do repeaters and bridges do?
NOTE:
In 10Base5 networks, nodes had to be placed at 2.5 meter intervals. With 10Base2, nodes had to be placed at a minimum 0.5 meters
apart.
H.W. # 55:
1) If you are in charge of networking in a facility, when would you use a hub and when would you use a switch?
DO NOW:
What is the distance limitation for a 10Base5 bus network, before having to regenerate the signal?
What is the distance limitation for a 10Base2 bus network, before having to regenerate the signal?
If you needed to needed to extend the distance, and therefore regenerate the signal, what device(s) could do this?
PROCEDURE:
Write the AIM and DO NOW.
Get students working!
Take attendance.
Go Over HW
Collect HW
Go over the Do Now
Assignment #1:
Look up the term repeater at www.techweb.com/encyclopedia. What is a repeater?
At what layer of the OSI model to repeaters work?
What are some benefits of repeaters?
What is the difference between a repeater and an amplifier?
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Technically, a repeater has just two ports, to connect two computers (network segments). If you have a multi-port repeater, that is called
a hub.41/42/
Assignment #2:
Although using repeaters has its benefits, it also has its
drawback in that the collision domain is extended thereby
reducing bandwidth for each user. To make sure that signals are
regenerated but also that only traffic destined for the other side
crosses the connectivity device, a bridge can be used.
A bridge only sends data to the other network segment
if the data is going to one of the nodes on the other side. It does
this by checking the destination MAC address with its table
(MAC to Port mapping). If the destination is on the other side, it
will forward the data. If not it won’t forward the data. It is that
simple.
A bridge learns MAC addresses and the ports they are
connected to when a computer sends data. The source MAC is in
the packet, so the bridge records who sent the data and what port
it came in from. Eventually all nodes will have sent out data, so
the bridge will have built-up a table of MAC addresses and the
port from which the MAC address came from. This table is
called a CAM table.
A multiport bridge is called a switch.
What are the advantages of using bridges?
What are the disadvantages of using bridges?
Sample Test Questions:
1) At what layer of the OSI model to bridges operate?
A) Physcial
B) Data Link
C) Network
D) Transport
2) At what layer of the OSI model to switches operate?
A) Physcial
B) Data Link
C) Network
D) Transport
3) At what layer of the OSI model to repeaters operate?
A) Physcial
B) Data Link
C) Network
D) Transport
4) At what layer of the OSI model to hubs operate?
A) Physcial
B) Data Link
C) Network
D) Transport
5) At which layers of the OSI model do bridges, hubs, and routers primarily operate, respectively?
A) Physical, Physical, Data Link
B) Data Link, Data Link, Network
C) Data Link, physical, Network
D) Physical, Data Link, Network
6) Which layer of the OSI model is responsible for converting data into signals appropriate for the transmission medium?
A) Application
B) Network
C) Data Link
D) Physical
7) Segmentation of a data stream happens at which layer?
A) Physical
B) Data Link
C) Network
D) Transport
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8) When data is encapsulated, which is the correct order?
A) Data, frame, packets, segments, bits
B) Segment, data, packet, frame, bits
C) Data, segment, packet, frame, bits
D) Data, segment, frame, packet, bits
9) Acknowledgements, sequencing, and flow control are characteristics of which OSI layer?
A) Layer 2
B) Layer 3
C) Layer 4
D) Layer 7
10) What is the purpose of flow control?
A) To ensure that data is retransmitted if an acknowledgement is not received.
B) To reassemble segments in that correct order at the destination device
C) To provide a means for the receiver to govern the amount of data sent by the sender
D) To regulate the size of each segment
11) At which layer of the OSI model would you find IP?
A) Application
B) Physical
C) Presentation
D) Network
E) Session