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1. What is the difference between a hub and a switch?

Hub Switch

LayerPhysical layer. Hubs are classified as Layer 1devices per the OSI model.

Data Link Layer. Networkswitches operate at Layer 2of the OSI model.

Ports4/12 ports Switch is multi port Bridge.

24/48 ports

Device TypePassive Device (Without Software) Active Device (With

Software) & Networking

deviceData

Transmissionform

Electrical signal or bits Frame (L2 Switch) Frame &Packet (L3 switch)

TransmissionType

Hubs always perform frame flooding; may beunicast, multicast or broadcast

First broadcast; then unicast& multicast as needed.

Function

To connect a network of personal computerstogether, they can be joined through a centralhub.

Allow to connect multipledevice and port can bemanage, Vlan can createsecurity also can apply

Table A network hub cannot learn or store MACaddress.

A network switch stores MACaddresses in a lookup table.

TransmissionMode

Half duplex Full duplex

Used in (LAN,MAN, WAN)

LAN LAN

BroadcastDomain

Hub has one Broadcast Domain. Switch has one broadcastdomain [unless VLANimplemented]

Definition An electronic device that connects many A network switch is a

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Hub Switch

network device together so that devices canexchange data

computer networking devicethat is used to connect manydevices together on acomputer network. A switchis considered more advancedthan a hub because a switchwill on send msg to devicethat needs or request it

CollisionsCollisions occur commonly in setups usinghubs.

No collisions occur in a full-duplex switch.

Spanning-Tree

No Spanning-Tree Many Spanning-tree Possible

Manufacturer s

Sun Systems, Oracle and Cisco Cisco and D-link Juniper

2. What is the significance of the IP address 255.255.255.255?

A special type of IP address is the limited broadcast address 255.255.255.255 . Abroadcast involves delivering a message from one sender to many recipients. Sendersdirect an IP broadcast to 255.255.255.255 to indicate all other nodes on the localnetwork (LAN) should pick up that message. This broadcast is 'limited' in that it does notreach every node on the Internet, only nodes on the LAN.

3. What is OSPF?

Open Shortest Path First (OSPF ) is a routing protocol for Internet Protocol (IP)networks. It uses a link state routing algorithm and falls into the group of interior routingprotocols, operating within a single autonomous system (AS).

4. What is difference between layer 2 Switch and Layer 3 Switch ?L-2 devices worked on mac address & L-3 devices worked on ipaddress.L-2 device more fast than the L-3 device.

layer 2 is for peer to peer communication,layer 3 is for process to processcommmunication

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layer 2 switching routing is not possibel but layer 3 switch routing is possible