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

The video tutorial explains the differences between private and public IP addresses, highlighting that private IPs are not routable on the global internet. It describes a typical private network setup with a router acting as a gateway, and how packets are routed and forwarded. The tutorial discusses the role of access lists in dropping packets with private IPs and introduces NAT as a solution for accessing the internet from private networks by translating private IPs to public ones.

Why are private IP addresses not routable on the global Internet?

• They are not recognized by global routing protocols.

• They are only used for secure communications.

• They are too complex to configure.

• They are too expensive to maintain.

In a private network setup, what role does the router play?

• It acts as a default gateway for devices.

• It assigns public IP addresses to all devices.

• It blocks all outgoing traffic.

• It provides wireless connectivity.

What happens to a packet with a private source IP when it reaches a backbone router?

• It is converted to a public IP.

• It is dropped due to access list filtering.

• It is stored for later processing.

• It is forwarded to the next hop.

How do routers typically make routing decisions?

• By checking the packet size.

• By only checking the destination IP.

• By only checking the source IP.

• By checking both source and destination IPs.

What is the primary function of NAT in a network?

• To block unauthorized access.

• To assign IP addresses to new devices.

• To translate private IPs to public IPs.

• To encrypt data packets.

When a web server responds to a translated IP address, what does the router do?

• It forwards the response to the original private IP.

• It stores the response for later use.

• It drops the response packet.

• It changes the response to a new public IP.

Why is NAT essential for devices with private IPs to access the Internet?

• It reduces the cost of Internet access.

• It provides faster Internet speeds.

• It allows private IPs to be recognized globally.

• It simplifies network configuration.