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Hello one more come to see CNPC which course prepared by or Khail Cisco do I get to see sandpits certification

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exam to in three parts and are Savitch route and T-shirt and we are starting with this be part and this

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first section will be about the basic switching concepts.

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We are starting with the harp harp is a common connection point for devices work and hubs that the word

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is commonly used to connect segments of a local area network.

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The Hub contains multiple ports.

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When a packet Arabs as one port it is applied to the other port so that all segments of the local learn

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and work can see all packets as you see them in the picture river hop.

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And we hear for ports over to Devizes

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if port one wants to communicate with port for for example the peccant is Flude to put two and Port

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three as well.

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And as you can see that that's an inefficient use of the bandwidth.

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The second one is we are going to talk about is Savitch and networks which is a computer networking

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device that connects devices together on a computer network by using packet switching to receive process

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and forward data to destination device and networks which is a multiple or bridge that uses hardware

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addresses to process and forward data at Linklater layer two of the PSI module and you can see a switch

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in here.

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This switch can be oversight layer two or layer tree as well.

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If you're are talking about the layered pre-speech that's a multilayer switch which can also make robing

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as well later.

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So it's make switching beds when they make table.

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They keep mac address stable.

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And forward the pickup's imports using that make up a stable so that provides efficient use of bandwidth

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and these devices can also provide power over the Internet and the security operations for us which

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we are going to talk about later in detail.

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Let's take a look to the broadcast domain or broadcast domain is a logical division of a computer network

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image all nodes courage each other by Bob Keth at datalink layer broadcast domain can be within the

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same law clarionet or segment or it can be bridged to other local area network segments.

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Any computer connected to the same switch is a member of the same broadcast domain.

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Further any computer connected to the same set of interconnected surveys is a member of the same broadcast

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domain.

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Please pay attention that others and other high later devices form boundaries between Burgas estimates

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and separating villans the way it's broadcast domains as well.

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Let's take a look to the picture now.

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We have four both Testament's answer.

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We have read the broadcast domains in here and as you can see that we have bandwidth twice the which

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is rather in here and also Whelan's are boundaries for the broadcast domain too.

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Let's take a look to the MAC addresses now.

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And Mekka address are for computer or printer or something.

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Any network device is a six byte unique identifier assigned to network interfaces for communications

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at that layer of a network segment.

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Megadoses are used as the network arrests for most terribly new technologies including Internet and

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Wi-Fi logically Meka addresses are used in the media access control protocols some layer of the was-I

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module and organisationally unique identifier is a 24 bit number that uniquely identifies a vendor manufacturer

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or other organization as you can see that the first portion of the MAC address is organizationally unique

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identifier.

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Other portion of the MAC address is universally administered address universally administered Everest's

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is uniquely assigned to a device by its manufacturer and that's it.

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And that's the second portion.

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Let's take a look at the Internet frame right now.

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It's in that frame consists some Feltz as you can see that in the picture they are pre-amble SFD we

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see where Mac Sendler Mac an optional relend tech and type filled payload and CRC checksum.

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For example let's take a look to the preamble first.

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Preamble communicates to the receiving devices whether a frame is coming and pro-white synchronization.

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The second fill is SFD we just start afresh.

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Delamater start him.

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Delegate who is responsible for specifying the beginning of the destination MAC address in the next

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byte and the other fields are receiver and sender Mac and an optional will intact and reheard type field

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in here.

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And we have a payload pad and CRC checksum.

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Let's take a look to the basics which you persist right now if the destination Meka is found in the

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camp table of the switch.

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The switch says the frame out of the corresponding port.

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This process is called forwarding.

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If the destination MAC address cannot be found in the camp table the form is sent to all other ports

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in the same Bil'in and this process is called Food Inc.

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If the destination MAC address of the receiving frame is the broadcast address which is

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f f f f f f f f f f f f this time the frame is sent to all the ports in the same villain.

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And this process is called also floating.