Lab - Determine the MAC Address of a Host

1. Table

Device	Interface	IP Address	Subnet Mask
PC	VLAN 1	192.168.1.2	255.255.255.0

4. s

• Determine the MAC address of a Windows computer on an Ethernet network using the ipconfig /all command.
• Analyze a MAC address to determine the manufacturer.

2. / Scenario

Every computer on an Ethernet local network has a Media Access Control (MAC) address that is burned into the Network Interface Card (NIC). Computer MAC addresses are usually displayed as 6 sets of two hexadecimal numbers separated by dashes or colons (example: 15-EF-A3-45-9B-57). The ipconfig /all command displays the computer MAC address. You may work individually or in teams.

1. Resources

• PC running Windows 10 with at least one Ethernet network interface card (NIC)
• Connectivity to the Internet
  16. 1: Locating the MAC Address on a Computer

In this part of the lab, you will determine the MAC address of a computer using the Windows ipconfig command.

1. 1. 19. 1: Display information for the command ipconfig / all
          1. Right-click on the Start button and select Command Prompt.
          2. Enter the ipconfig /all command at the command prompt.
      20. 2: Locate the MAC (physical) address(es) in the output from the ipconfig /all command

Use the table below to fill in the description of the Ethernet adapter and the Physical (MAC) Address:

Description	Physical Address
blank	blank
blank	blank
blank	blank

Question:

How many MAC addresses did you discover in your PC?

Type your answers here.

1. 16. 2: Analyzing the s of a MAC Address

Every Ethernet network interface has a physical address assigned to it when it is manufactured. These addresses are 48 bit (6 bytes) long and are written in hexadecimal notation. MAC addresses are made up of two parts. One part of the MAC address, the first 3 bytes, represents the vendor who manufactured the network interface. This part of the MAC is called the OUI (Organizationally Unique Identifier). Each vendor who wants to make and sell Ethernet network interfaces must register with the IEEE in order to be assigned an OUI.

The second part of the address, the remaining 3 bytes are the unique ID for the interface. All MAC addresses that begin with the same OUI must have unique values in the last 3 bytes.

In this example, the physical MAC address for the Ethernet LAN interface is D4-BE-D9-13-63-00.

Manufacturer OUI	Unique Identifier for the Interface	Vendor Name
D4-BE-D9	13-63-00	Dell Incorporated

1. 1. 19. 1: List MAC addresses discovered by you and your classmates in previous part.

List the 3-byte Manufacturer OUI and the 3-byte unique interface identifier. You will fill in the Vendor name in the table below.

Manufacturer OUI	Unique Identifier for the Interface	Vendor Name
D4-BE-D9	13-63-00	Dell Incorporated
blank	blank	blank
blank	blank	blank

1. 1. 19. 2: Lookup the vendors who are the registered owners of the OUI that you listed in the table.
          1. Wireshark.org provides an easy to use lookup tool at https://www.wireshark.org/tools/oui-lookup.html. Use this tool or use the internet to search for other ways to identify an OUI.
          2. Use the information that you found to update the vendor column in the chart in Step 1.

Question:

How many different vendors did you discover?

Type your answers here.

51. 1. Why might a computer have more than one MAC address?

Type your answers here.

1. 2. The sample output from the ipconfig /all command shown previously had only one MAC address. Suppose the output was from a computer that also had wireless Ethernet capability. How might the output change?

Type your answers here.

1. 3. Try connecting and disconnecting the network cable(s) to your network adapter(s) and use the ipconfig /all again. What changes do you see? Does the MAC address still display? Will the MAC address ever change?

Type your answers here.

1. 4. What are other names for the MAC address?

Type your answers here.