面试题与答案

Dynamic Host Configuration Protocol (DHCP) is used to automatically assign IP addresses and other network configuration information to devices on a network.

Example:

For example, when a computer connects to a network, DHCP ensures it receives a valid IP address, subnet mask, and default gateway without manual configuration.

TCP (Transmission Control Protocol) is connection-oriented and ensures reliable data delivery through features like acknowledgment and retransmission. UDP (User Datagram Protocol) is connectionless and provides faster, but less reliable, communication.

Example:

TCP is commonly used for applications like web browsing, while UDP is suitable for real-time applications like online gaming or video streaming.

NAT is used to map private IP addresses within a local network to a single public IP address. It enables multiple devices in a local network to share a common public IP address for internet communication.

Example:

When a device with a private IP address sends a request to the internet, the NAT router replaces its private IP with the public IP for external communication.

A firewall is a security device that monitors and controls incoming and outgoing network traffic based on predetermined security rules. It acts as a barrier between a secure internal network and untrusted external networks.

Example:

Firewalls can block unauthorized access attempts, filter traffic based on protocols, and prevent certain types of cyber attacks.

RAID (Redundant Array of Independent Disks) is a data storage technology that combines multiple physical disk drives into a single logical unit for the purpose of data redundancy, performance improvement, or both.

Example:

For example, RAID 1 mirrors data across two drives, providing redundancy in case of a disk failure.

A 404 error occurs when a web server cannot find the requested page. It is an HTTP status code indicating that the client's request was valid, but the server could not locate the requested content.

Example:

If a user tries to access a non-existent page on a website, the server may respond with a 404 error, indicating that the requested resource was not found.

The ping command is used to test the reachability of a host on an Internet Protocol (IP) network. It sends ICMP (Internet Control Message Protocol) echo requests to the target host and measures the round-trip time for the responses.

Example:

Running 'ping www.google.com' can help determine if your computer can communicate with the Google server and measure the network latency.