Concept of URL and IP Address. Various fields in IP header. How an IP address is Assigned to host?

Short Answer Explanation

URL (Uniform Resource Locator) addresses are like home addresses for your website. They help your computer to find the website you wanted to visit on the internet. IP (Internet Protocol Address) is like a unique numbers for each devices connected to the internet. It helps computers to find each other online.

When you type a URL into your browser, your computer uses the internet to identify an IP address which matches the url. Then, it uses this IP address to visit the website.

An IP datagram is a packet of data sent across the internet. The IP datagram header is like the envelope for a letter. It contains important information for delivering the packet, such as where it’s from and where it’s going.

Getting an IP address for a device works a bit like getting a library card. Your internet service provider gives your device an IP address so it can access the internet. This way, your device can send and receive information online.

Detailed Answer Explanation

Understanding URL and IP Address

A URL (Uniform Resource Locator) acts as a web address. It’s a way to tell your browser where to find a specific website on the vast internet. For example, typing “www.example.com” into your browser directs it to a particular website.

An IP Address (Internet Protocol Address), on the other hand, is a unique series of numbers separated by periods. It identifies each device on the internet or a local network. Think of it as your home’s postal address but for your computer or phone on the internet.

How URLs and IP Addresses Work Together

When you enter a URL in your browser, something called DNS (Domain Name System) converts the URL into an IP address. This process is like looking up a phone book to find someone’s number. The DNS finds the IP address so your browser can visit the website.

IP Datagram Header Fields

An IP datagram is a package of information sent across the internet. The header of this datagram contains several fields:

1. Version: This tells us the IP protocol version.
2. Header Length: Indicates the header’s size.
3. Type of Service: Describes the datagram’s service quality.
4. Total Length: The length of the entire IP datagram.
5. Identification, Flags, Fragment Offset: These are used for assembling datagrams in the correct order.
6. Time to Live (TTL): Determines how long the datagram is allowed to travel before being discarded.
7. Protocol: Indicates the protocol used in the data portion.
8. Header Checksum: Helps check for errors in the header.
9. Source and Destination IP Address: These show where the datagram is from and where it’s going.

Assigning an IP Address to a Host

Devices get their IP addresses in a few ways. One common method is through DHCP (Dynamic Host Configuration Protocol). When you connect to the internet, your router asks for an IP address from your ISP (Internet Service Provider). DHCP automatically assigns an IP address to your device. It’s like when you go to a coffee shop, and they give you a Wi-Fi code to connect to the internet.

Another way is through static assignment. This is when a device is given a specific IP address that doesn’t change. It’s like having a reserved parking spot. This method is often used for servers that need a constant address.

Examples and Applications

• Browsing the Web: When you search for a website, your computer uses the URL to find the IP address and connect to the site.
• Emailing: Behind the scenes, sending an email uses IP addresses to route your message to the right place.
• Online Gaming: When you play games online, your console or PC uses an IP address to connect to game servers.

In summary, URLs and IP addresses are essential for navigating the vast world of the internet. URLs make it easy for us to remember and enter web addresses, while IP addresses ensure data reaches its correct destination. The IP datagram header plays a crucial role in guiding this data through the internet, much like directions on a map. Assigning an IP address, whether dynamically or statically, connects devices to the internet highway, enabling them to communicate and access online content.