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In this video we're going to discuss hexadecimal binary and decimal conversions with an emphasis on

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the conversion of hexadecimal numbers to decimal.

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In previous videos I explained how to convert binary to decimal and decimal to binary.

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Please refer to those videos.

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If you're not sure how to do binary to decimal and decimal to binary conversions hexadecimal is really

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important in networking.

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As an example on my Windows machine if I type IP config for special and I'm going to pipe that to more

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so that we see one page at a time what you'll notice is that on my network interface card.

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So my Local Area Connection.

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I have a Broadcom network stream gigabit ethernet card with this MAC address so hexadecimal is used

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to identify MAC addresses but it's also used to identify IP version 6 addresses.

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Let's discuss MAC addresses of ping a device.

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So this is my default gateway.

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As you can see over there when I type up a.

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I can see that the IP address of the default gateway was resolved to this MAC address as an example

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if I ping 191 except 56 to 40 and then do all Peiffer ne.

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I can see that that IP address was resolved to this MAC address.

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Now that is a Cisco router so I'll telnet to the router luggin show interface if 0 0.

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So here's the command shows me the IP address and MAC address of the Rodda I'll open up another cmd

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prompt in Windows so all hyphenating notice on my local PC that IP address of the router will be here.

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Has been resolved to this MAC address which is correct.

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That's the MAC address of the rod it now on a router.

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You have the MAC address that it uses as well as a burned in address or B.A address that's the address

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that was burnt into the network interface card by the manufacturer.

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You also have something similar in Windows so this is my network interface card in Windows and if I

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go to properties and configure the network interface card under advanced I have the option network address

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so the MAC address of my local network card

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is shown here.

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That I can change that to quadruple they triple B quadruple C as an example.

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So I'm changing the MAC address from what the manufacturer said it to to this new MAC address I may

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lose my telnet connection because I've changed the MAC address but I could telnet back to the router

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show interface if 0 0 shows me the MAC address on my router as it's configured and the boot in address

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and I could do something similar.

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So on the Cisco router I could specify the MAC address as let's say a b b b c.

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So I've changed the MAC address of the interface.

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So show interface 0 0.

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Notice the MAC address is now this.

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Previously the MAC address was this up.

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Hi FNet shows me the new MAC address on my local Windows machine and show up on the router shows me

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MAC addresses of devices in the network so the IP address on my local PC is 1 9 2 1 6 8 56 199

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and you can see that MAC address in the output here.

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Some of these other duplicate MAC addresses are because of network address translation that's being

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configured on the router so I wouldn't worry about that for the moment.

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What I'd like to see is when I look at the running configuration of this router I have changed the MAC

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address to this valley

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and when I look at the cache on the PC I can see that entry on my local PC so understanding hexadecimal

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can be important in networking because simple things such as working with MAC addresses or IP version

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6 require that you have an understanding of hexadecimal.

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So I'll not explain how to convert hexadecimal to binary and two decimal.