1. The document discusses different types of networking devices like repeaters, bridges, routers, and gateways and how they operate at different layers of the OSI model.
2. It provides examples of how these devices like repeaters, bridges, and routers are used to connect different local area networks and extends the physical length and coverage of a network.
3. The document also discusses concepts like routing tables, link state routing, and the Dijkstra algorithm that are used to determine the best paths between nodes in a network.
2. Connection devices with the OSI
model
7 layers of OSI model
All 7 layers
1 Layer
Physical data link, Physical +
Physical
Network Layers Datalink layer
3 layers
2 layers
Gateway Router Bridge Repeater
3. A repeater in the OSI model
Device A Device B
Repeater
Subnet R Subnet
7 7
OSI LAYERS
OSI LAYERS
6 6
5 5
4 4
3 3
2 2
Repeater extends the physical
1 length of a network
1
R
6. Bridge to connect two LANs
LAN 1 LAN 2
A A
HUB HUB
B B
Bridge
C C
D D
7. A Bridge in the OSI model
Device A Device B
Repeater
Subnet R Subnet
7 7
OSI LAYERS
OSI LAYERS
6 6
5 5
4 4
3 3
2 2
1 1
1 Data link
2 Physical
8. Functions of a Bridge
Seg ment 1
Packet
A B
Bridge
e nt 2
Se gm
C Packet
D
9. Three types of bridges
I. Simple bridges
I. Learning bridges
I. Multiport bridges
10. Simple bridge - 1
• Primitive type
• Least expensive
• Links two segments
• Contains a table that lists the addresses of
all the stations in each of them
• Addresses are to be entered manually
• Before functioning the operator must set
down & program the addresses of every
station
11. Use of routers to connect LANs
Server
Device 4
Device 1
Token Ethernet Server
ring hub hub
Device 2
Device 5
Bridge
Device 3
Device 6
12. A router in the OSI Model
Device Repeater Device
A
B
Network R Network
7 7
OSI LAYERS
OSI LAYERS
6 6
5 5
4 4
3 3
2 2
Network
1 1
Data link
Physical
13. Routers in an internet
Router
Network B
Network A
Router
Router
Router
Network E
Network C
Router
Router
Network D
14. Route for the packets from
network A to network D
Network B Network C
Network A
Network D
Network Q
15. Use of gateways (connecting
LANs and Mainframe)
Front-
end
Server Device 4
Main
frame
Device 1 Server
Token
Ethernet
ring hub
hub
Device 2 Device 5
Device 3
D i 6
16. A Gateway in the OSI model
Device Device
Network Gateway Network
A B
7 7 7
OSI LAYERS
OSI LAYERS
6 6 6
5 5 5
4 4 4
3 3 3
2 2 2
1 1 1
33. “Like” us on Facebook:
p // /
http://www.facebook.com/welearnindia
“Follow” us on Twitter:
http://twitter.com/WeLearnIndia
http://twitter com/WeLearnIndia
Watch informative videos on Youtube:
http://www.youtube.com/WelingkarDLP