Exam: 200-301: Cisco Certified Network Associate (CCNA) 0 Likes
Refer to the exhibit. Which outcome is expected when PC_A sends data (CCNA 200-301)
Refer to the exhibit. Which outcome is expected when PC_A sends data to PC_B after their initial communication?
A) The source MAC address is changed.
B) The destination MAC address is replaced with ffff.ffff.ffff.
C) The source and destination MAC addresses remain the same.
D) The switch rewrites the source and destination MAC addresses with its own.
Solution
Correct answer: C) The source and destination MAC addresses remain the same.
In a TCP/IP network, each device, such as PC A and PC B, is assigned an IP address for communication. When PC A wants to send data to PC B, it first creates an IP packet containing the destination IP address of PC B. This packet then needs to be encapsulated into an Ethernet frame, which operates at Layer 2 of the OSI model. To determine the destination MAC address, PC A looks up the MAC address associated with PC B's IP address, typically using Address Resolution Protocol (ARP).
Once PC A obtains PC B's MAC address, it uses it as the destination MAC address in the Ethernet frame. When the frame reaches Switch SW1, the switch examines the destination MAC address and consults its MAC address table to determine which port is associated with that MAC address. It then forwards the frame out of the corresponding port, enabling it to reach PC B.
Throughout this process, the switch does not modify either the source or destination MAC addresses inside the frame. They remain unchanged as the frame traverses the network from PC A to PC B.
Category: Network Fundamentals