A Cisco router receives an IPv4 packet destined for a remote network. Place the router forwarding decision and packet processing steps in the correct chronological order from first to last.
- 1Extract the destination IPv4 address from the incoming packet header.
- 2Evaluate the IPv4 routing table and select candidate routes based on the Longest Prefix Match (LPM).
- 3Break ties between competing routes with identical prefix lengths using Administrative Distance, followed by metric.
- 4Determine the egress exit interface and next-hop IPv4 address from the selected best route entry.
- 5Resolve the next-hop Layer 2 MAC address, decrement the IPv4 TTL by 1, recalculate the checksum, and transmit the frame.
Cevap
The correct order of router forwarding decision logic begins with inspecting the destination IP header, evaluating the routing table using Longest Prefix Match, resolving equal prefix length ties using Administrative Distance and metric, identifying the next-hop IP and exit interface, and performing Layer 2 header rewriting along with TTL decrement prior to frame transmission.
Router forwarding logic follows a deterministic sequence: packet IP inspection -> Longest Prefix Match evaluation -> Administrative Distance/metric tie-breaking for equal prefixes -> next-hop and exit interface resolution -> Layer 2 MAC resolution, TTL decrement, and frame forwarding.
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Router Forwarding Decision Logic