220-1101 Question 149
Select 2DynamicA technician is setting up a small office router for 12 employees. The ISP provided a single public IP address, but every employee needs Internet access from a separate workstation, and the company wants devices to receive IP settings automatically without manual configuration. Which TWO router features should the technician configure to meet these requirements?
- A
Enable DHCP on the LAN interface
- B
Enable NAT/PAT on the WAN interface
- C
Configure port forwarding for each workstation
- D
Assign static public IP addresses to all client PCs
- E
Disable DNS and use only APIPA addressing
Show answer and explanation
Correct answers: A, B
Explanation
The best answer is to configure DHCP and NAT/PAT. DHCP is the standard service for dynamically assigning network settings to clients, reducing administrative overhead and minimizing configuration errors. NAT/PAT is required because a single public IP must be shared among many private internal devices. In SOHO environments, routers commonly provide both functions together. This aligns with standard networking best practices and common vendor documentation for home and small business routers: use private IPv4 addressing internally, DHCP for automatic client configuration, and NAT/PAT to enable many devices to access the Internet through one public IPv4 address.
- A. Correct.
Correct. DHCP dynamically assigns IP configuration information such as IP address, subnet mask, default gateway, and often DNS server addresses to client devices. In a small office, this is the standard way to avoid manually configuring each workstation and is a common A+ Core 1 networking objective.
- B. Correct.
Correct. NAT/PAT allows multiple internal private IP addresses to share one public IP address when accessing the Internet. Because the ISP supplied only a single public IP, the router must translate internal addresses to that public address. PAT, often called NAT overload, distinguishes sessions by port numbers and is the practical solution in this scenario.
- C. Incorrect.
Incorrect. Port forwarding is used to direct unsolicited inbound traffic from the Internet to a specific internal host or service, such as a web server or remote desktop system. It does not provide general outbound Internet access for all workstations and does not solve dynamic client addressing.
- D. Incorrect.
Incorrect. The office has only one public IP address from the ISP, so assigning static public IPs to all clients is not possible. Even if multiple public IPs were available, directly exposing every PC to the Internet would be poor practice compared with using private addressing behind a router.
- E. Incorrect.
Incorrect. APIPA assigns self-generated 169.254.x.x addresses only when a device cannot contact a DHCP server, and those addresses do not provide normal routed Internet access. Disabling DNS would also prevent users from resolving hostnames, making Internet access less functional, not more.