Physical address 109 346 now there are actually two

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Physical Address 1:09-3:46 Now there are actually two different types of addresses that are used on a network. There is the physical hardware address and there is the logical address. Let's take a look at the characteristics of these addresses, starting with the physical address. The physical address of a device is also called the media access control address, or MAC address.MAC addresses have a few characteristics that you should be aware of. First, MAC addresses are burned into the read-only memory of every single network interface. No matter the transmission medium. This makes it next to impossible to change the device's MAC address. Second, MAC addresses are globally unique. No other network interface in the world has the same MAC address. And the last characteristic is that MAC addresses can be used to identify the manufacturer of the network interface card. Here's an example of a MAC address. Now this is actually a MAC address in a hexadecimal form. MAC addresses in reality are a 48 bit binary number, however, you will always be working with MAC addresses as a 12 character hex number. MAC addresses are typically grouped into six groups of two hexadecimal digits which are separated by hyphens or colons. The first six characters of any MAC address can be used to identify the manufacturer of the device. Every manufacturer is assigned a unique six digit sequence by the Institute of Electrical and Electronic Engineers, or IEEE. And manufacturers are required to use these first six digits in the MAC address of every network interface they create. Because of this, all network interface cards created by a specific manufacturer will have the same first six MAC address numbers. The last six digits in a MAC address are used to identify that particular network interface. By using these two number sets, the manufacturer and the interface, no two network interfaces should everhave the same MAC address. Because of this, MAC addresses are used to send information to specific hosts.
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Remember, network communications require an address, both from the sending host and the receiving host. So when a host needs to send information, it puts it into what's called a network packet, which is composed of the data we are sending and a header. This header contains two pieces of information, the sending host's MAC address and the receiving host's MAC address. By inspecting the to and from address in the packet, hosts on the network can communicate with each other. Now this is how physical network addressing works, but remember, networks also use logical addresses, and these are the addresses you are probably more familiar with. Logical Address 3:47-5:26 Logical addresses are assigned by software, and as such, can be changed. Logical addresses are used by a lot of different network protocols. However, the most common type of logical addresses are those assigned by the IP protocol.
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