You are implementing the company networks for a startup. Which of the following is least related to the data link layer?
A. Configuring the physical address of a network interface card.
B. Implementing a linear network with token passing.
C. Splitting traffic by VLAN tagging.
D. Binding multiple logical addresses to a network interface card.
Kindly be reminded that the suggested answer is for your reference only. It doesn’t matter whether you have the right or wrong answer. What really matters is your reasoning process and justifications.
My suggested answer is D. Binding multiple logical addresses to a network interface card.
The Data Link layer can be divided into two sub-layers: the Media Access Control (MAC) and Logical Link Control (LLC) layer.
Logical Link Control (LLC)
VLAN splits traffic by tagging Ethernet frames, e.g., 802.1Q. It can be viewed as part of the logical link control.
Media Access Control (MAC)
Common network topologies (shapes) are bus (linear), ring, tree, and mesh. Typical media access control mechanisms are CSMA/CD, CSMA/CA, and Token Passing. A linear network with token passing is a token bus network, e.g., the outdated IEEE 802.4.
- Physical addresses are commonly known as MAC addresses. The original MAC address is uniquely assigned or burned by the manufacturer, also known as the universally administered addresses (UAA), which can be overwritten by a network administrator.
- The newly assigned MAC address is known as locally administered addresses (LAA).
- Nowadays, most of network interface drivers and virtual machines allow system administrators or engineers to modify the MAC address or assign LAA.
Sitting above the MAC sub-layer, logical addresses typically imply the counterpart of physical addresses. A network interface can support multiple protocols simultaneously, such as IPX/SPX, IPv6, and IPv6. We can assign one or more logical addresses to a network interface on the protocol basis.
The snapshot above is the result of the Windows command “ipconfig /all.” We can see both IPv4 and IPv6 addresses are configured.
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