In this video we're going to discuss hexadecimal binary and decimal conversions with an emphasis on
the conversion of hexadecimal numbers to decimal.
In previous videos I explained how to convert binary to decimal and decimal to binary.
Please refer to those videos.
If you're not sure how to do binary to decimal and decimal to binary conversions hexadecimal is really
important in networking.
As an example on my Windows machine if I type IP config for special and I'm going to pipe that to more
so that we see one page at a time what you'll notice is that on my network interface card.
So my Local Area Connection.
I have a Broadcom network stream gigabit ethernet card with this MAC address so hexadecimal is used
to identify MAC addresses but it's also used to identify IP version 6 addresses.
Let's discuss MAC addresses of ping a device.
So this is my default gateway.
As you can see over there when I type up a.
I can see that the IP address of the default gateway was resolved to this MAC address as an example
if I ping 191 except 56 to 40 and then do all Peiffer ne.
I can see that that IP address was resolved to this MAC address.
Now that is a Cisco router so I'll telnet to the router luggin show interface if 0 0.
So here's the command shows me the IP address and MAC address of the Rodda I'll open up another cmd
prompt in Windows so all hyphenating notice on my local PC that IP address of the router will be here.
Has been resolved to this MAC address which is correct.
That's the MAC address of the rod it now on a router.
You have the MAC address that it uses as well as a burned in address or B.A address that's the address
that was burnt into the network interface card by the manufacturer.
You also have something similar in Windows so this is my network interface card in Windows and if I
go to properties and configure the network interface card under advanced I have the option network address
so the MAC address of my local network card
is shown here.
That I can change that to quadruple they triple B quadruple C as an example.
So I'm changing the MAC address from what the manufacturer said it to to this new MAC address I may
lose my telnet connection because I've changed the MAC address but I could telnet back to the router
show interface if 0 0 shows me the MAC address on my router as it's configured and the boot in address
and I could do something similar.
So on the Cisco router I could specify the MAC address as let's say a b b b c.
So I've changed the MAC address of the interface.
So show interface 0 0.
Notice the MAC address is now this.
Previously the MAC address was this up.
Hi FNet shows me the new MAC address on my local Windows machine and show up on the router shows me
MAC addresses of devices in the network so the IP address on my local PC is 1 9 2 1 6 8 56 199
and you can see that MAC address in the output here.
Some of these other duplicate MAC addresses are because of network address translation that's being
configured on the router so I wouldn't worry about that for the moment.
What I'd like to see is when I look at the running configuration of this router I have changed the MAC
address to this valley
and when I look at the cache on the PC I can see that entry on my local PC so understanding hexadecimal
can be important in networking because simple things such as working with MAC addresses or IP version
6 require that you have an understanding of hexadecimal.
So I'll not explain how to convert hexadecimal to binary and two decimal.