A Cisco router receives an IPv4 packet destined for . Place the routing table lookup and packet forwarding steps in the correct chronological order from first to last.
- 1Extract the destination IPv4 address from the incoming packet header.
- 2Compare the destination IPv4 address against all network prefixes in the routing table.
- 3Select the matching static or dynamic route entry with the longest prefix length (most specific mask).
- 4Identify the next-hop IPv4 address or direct egress interface associated with the selected route.
- 5Encapsulate the IPv4 packet into a Layer 2 frame and transmit it out the egress interface.
Answer
The correct forwarding sequence begins with parsing the packet header to extract the destination IP, searching the routing table using longest prefix match logic, selecting the most specific matching prefix, identifying the next-hop IP or exit interface, and finally encapsulating the packet into a Layer 2 frame for egress transmission.
The correct order follows standard Cisco IOS router packet forwarding logic: extracting the destination IPv4 address, evaluating routing table prefixes, applying the longest prefix match (LPM) rule to select the best route, resolving the next-hop IP address or exit interface, and performing Layer 2 frame encapsulation prior to egress.
Step-by-Step Solution
Key Concept
IPv4 Routing Table Lookup and Longest Prefix Match Forwarding Logic