This document defines and describes several common networking devices and the layers in which they operate. It discusses gateways, hubs, switches, repeaters, routers, and bridges. Gateways can operate at any OSI model layer and join different network types. Hubs operate at layer 1 and broadcast traffic to all ports. Switches are more advanced than hubs, sending messages only to requesting devices. Repeaters amplify and resend weakened signals. Routers forward data between networks and are located at gateways. Bridges create separate collision domains and filter traffic by MAC address. The document also compares hubs and switches, noting switches are active devices that can send traffic selectively while hubs are passive and broadcast to all ports.

1. HarisH r pillai
Ce-a(a2)
120120107025

2. list of networking
deviCes:-
Gateway
Hub
Switch
Repeater
Routers
Bridge

3. gateway
A network gateway is an internetworking system capable
of joining together two networks that use different base
protocols. A network gateway can be implemented
completely in software, completely in hardware, or as a
combination of both. Depending on the types of protocols
they support.
network gateways can operate at any level of the OSI
model.

4. Hub
Hub is a device for connecting multiple Ethernet
devices together and making them act as a single
network segment. It has multiple input/output (I/O)
ports, in which a signal introduced at the input of any
port appears at the output of every port except the
original incoming.
A hub works at the physical layer (layer 1) of the OSI
model

5. SwitcH
A network switch is a computer networking device that
is used to connect devices together on a computer
network by performing a form of packet switching.
A network switch is considered more advanced than a
hub because a switch will only send a message to the
device that needs or requests it, rather than
broadcasting the same message out of each of its ports.

6. RepeateR
Signal attenuation or signal loss – signal degrades
over distance
Repeaters clean, amplify, and resend signals that are
weakened by long cable length.
Built-in to hubs or switches

7. RouteRs
 A router is a device that forwards data packets along
networks. A router is connected to at least two
networks, commonly two LANs or WANs or a LAN
and its ISP's network. Routers are located at gateways,
the places where two or more networks connect.

8. BRidge
A layer 2 device designed to create two or more LAN segments,
each of which is a separate collision domain.
The purpose is to filter traffic on a LAN, to keep local traffic
local, yet allow connectivity to other segments of the network.
Filter traffic by looking at the MAC address
Frame filtering

9. devices and the layeRs
at which they opeRate
Name of Layer Device
Network
Data Link
Physical
Routers, layer 3
switches
Switches,
bridges, NIC’s
Hubs

10. Hub vs. switcH
Hubs switcH
 An electronic device that connects
many network device together so that
devices can exchange data
 Physical layer. Hubs are classified as
Layer 1 devices per the OSI model.
 4/12 ports Switch is multi port Bridge.
 Passive Device (Without Software)
 Manufacturers Sun Systems, Oracle
and Cisco Cisco and D-link Juniper
A network switch is a computer
networking device that is used
to connect many devices
together on a computer
network.
Physical layer. Hubs are
classified as Layer 1 devices per
the OSI model.
Switch is multi port Bridge.
24/48 ports.
Active Device (With Software)
& Networking device
Manufacturers Cisco and D-link
Juniper