World of Computer Networking Your CCNA start - Working of Network Address Translation (NAT)

The video tutorial explains how routers process IP packets by performing routing table lookups, decrementing TTL, and recalculating header checksums. It discusses how routers can modify packet headers, including source and destination IP addresses, especially when Network Address Translation (NAT) is enabled. The tutorial provides a detailed example of NAT, showing how private IP addresses are replaced with public ones for outgoing packets and vice versa for incoming packets. It concludes with an introduction to static NAT.

What is one of the first actions a router takes upon receiving an IP packet?

• It compresses the packet data.

• It performs a lookup of its routing table.

• It changes the packet's destination port.

• It encrypts the packet.

In the context of NAT, what can a router modify in an IP packet?

• Only the packet's payload

• The source and destination IP addresses and ports

• The packet's encryption method

• The packet's TTL value

What is the primary purpose of replacing a private IP address with a public IP address in NAT?

• To increase the packet's size

• To ensure the packet can be routed over the internet

• To decrease the packet's latency

• To encrypt the packet's contents

When a router performs destination NAT on incoming packets, what is it primarily modifying?

• The packet's payload

• The destination IP address

• The packet's TTL value

• The source port

What is the most common modification a router makes to outgoing packets when using NAT?

• Replacing the source IP address

• Changing the packet's payload

• Modifying the packet's TTL value

• Altering the packet's encryption