This document discusses five categories of connecting devices in a network: passive hubs, active hubs, bridges, two-layer switches, routers, three-layer switches, and gateways. It provides brief explanations and examples of repeaters, bridges, and routers. Repeaters connect segments of a LAN by forwarding every frame without filtering. Bridges have a table used for filtering decisions and connect LANs without changing frame addresses. Routers connect independent LANs and WANs.

1. 15.1
Connecting LANs
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2. 15.2
CONNECTING DEVICESCONNECTING DEVICES
In this section, we divide connecting devices into fiveIn this section, we divide connecting devices into five
different categories based on the layer in which theydifferent categories based on the layer in which they
operate in a network.operate in a network.
Passive Hubs
Active Hubs
Bridges
Two-Layer Switches
Routers
Three-Layer Switches
Gateways
Topics discussed in this section:Topics discussed in this section:

3. 15.3
Five categories of connecting devices

4. 15.4
A repeater connecting two segments of a LAN

5. 15.5
A repeater connects segments of a LAN.
Note

6. 15.6
A repeater forwards every frame;
it has no filtering capability.
Note

7. 15.7
A repeater is a regenerator,
not an amplifier.
Note

8. 15.8
Function of a repeater

9. 15.9
A hierarchy of hubs

10. 15.10
A bridge has a table used in
filtering decisions.
Note

11. 15.11
A bridge connecting two LANs

12. 15.12
A bridge does not change the physical
(MAC) addresses in a frame.
Note

13. 15.13
A learning bridge and the process of learning

14. 15.14
Loop problem in a learning bridge

15. 15.15
Routers connecting independent LANs and WANs

16. 15.16
Computer Science & Engineering
Assignment
Semester- VI (I & II) Branch: CSE
Subject with Code: Computer Networks (IT-305-F)
Q:1 Explain the Following.
1.Hub
2.Router
3.Bridge
4.Repeater