Which Component Forwards Packets Between Different Networks
[sampleXML/xmlfile-56_1.png] Refer to the exhibit. When PC-A sends traffic to PC-B, which network component is in charge of receiving the packet from PC-A, verifying the IP addresses, and forwarding the packet to PC-B?
Community Insight
The question tests the functional difference between Layer 2 and Layer 3 devices, and the trap is choosing the switch because it is shown carrying traffic in the exhibit.
This CCNA question tests which network device receives a packet from PC-A, inspects the IP addresses, and forwards it toward PC-B. The correct answer is a router, because inter-network forwarding requires Layer 3 logical addressing verification.
Option B, Layer 2 switch, is the most tempting wrong pick because switches populate the physical path between the PCs; however, a switch forwards frames using MAC addresses and never verifies IP addresses or routes between different subnets.
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Expert Analysis
Why the Answer Is Correct
A router is the device responsible for receiving a packet, checking the destination IP address against its routing table, making a forwarding decision, and sending the packet onward toward PC-B. Because PC-A and PC-B reside in different networks, only a Layer 3 device can perform this logical addressing verification and inter-network forwarding. As rictorres333 observed, "The key word is "packet"" — packets are a Layer 3 term, and routers are the components that process packets, not frames.Why the Other Options Are Wrong
A Layer 2 switch (B) forwards Ethernet frames based on MAC addresses learned in its CAM table and operates within a VLAN or broadcast domain; it does not inspect or verify IP addresses. A load balancer (C) distributes traffic across multiple servers for performance and redundancy, and a firewall (D) enforces security policy by permitting or denying traffic — neither is the default component described by the packet-receive/verify/forward behavior in the question. Both would be additional services layered onto a topology, not the basic inter-network forwarding function being tested.Community Comment Notes
Belinda explained that "Switches send traffic in layer 2 and within the same VLA" while routers route traffic across different subnets at Layer 3, and maximus_007 echoed that switches "forward frames learned via ARP." ZUMY, harkindeylee, and country_rooted all independently landed on A, with country_rooted noting that the phrase "verify" in the stem already points to the router.Official Reference
Exam Strategy
On CCNA questions, key nouns are your signal: "packet" and "IP address" mean Layer 3 and a router, while "frame" and "MAC address" mean Layer 2 and a switch. Confirm the exhibit shows two different networks, since a router is only required when traffic must leave its own subnet.
Frequently Asked Questions
Why doesn't a Layer 2 switch forward the packet between PC-A and PC-B?
A Layer 2 switch forwards Ethernet frames using MAC addresses within the same broadcast domain or VLAN. It never inspects IP addresses, so it cannot route between two different networks.
How does the word "packet" signal the correct answer?
"Packet" refers to a Layer 3 PDU carrying IP addresses, and only a router processes packets. Switches work with frames at Layer 2, making the router the only device that can verify IPs and forward between subnets.
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