DNS Cache

Cyber Space CEC Videos

18 Nov 201901:28

Summary

TLDRThe script explains the concept of a 'DNS Cache,' a hidden treasure of information on websites visited, which enhances internet navigation speed and efficiency. When visiting a site for the first time, a DNS request is sent, and the server responds with the corresponding IP address. Subsequent visits are faster as the browser checks the local DNS cache before making a new request. This cache is a valuable resource that, while not making us rich, significantly improves our internet experience by saving time on searching.

Takeaways

💡 Every computer has a cache, which is a storage of information about websites visited, not a treasure that improves the state of the browser.
🔍 When visiting a website for the first time, the browser sends a DNS request, and the DNS server responds with an appropriate IP address.
🔁 On subsequent visits to the same site, the process is quicker because the browser checks its local DNS cache before making a DNS request to the server.
🚀 The speed of internet navigation is greatly influenced by the number of requests sent to servers and the responses received by clients.
💾 DNS Cache is a local file on the computer that stores domain names along with their corresponding IP addresses to speed up website access.
📚 The term 'cache' refers to a resource in our fast memory that saves us time by avoiding the need to search repeatedly.
🌐 When a domain name is entered in the browser, the computer first checks the local DNS cache, and only if the desired IP address is not found will it request it from the DNS server.
🛑 The cache does not make us rich, but it does make internet access fast and efficient.
🔑 The script emphasizes the importance of cache in improving the user experience on the internet by reducing load times.
📈 The script provides insight into how caching mechanisms work to enhance the efficiency of internet navigation.

Q & A

What is the purpose of a computer's cache?
-A computer's cache is used to store information about websites visited to improve the speed and efficiency of internet access.
What happens when you visit a website for the first time?
-When visiting a website for the first time, the browser sends a DNS request, and the DNS server responds with the appropriate IP address.
What is the role of DNS in accessing a website?
-DNS (Domain Name System) translates domain names into IP addresses that computers use to access websites.
Why does the browser save DNS requests?
-The browser saves DNS requests to reduce the time it takes to load a website by avoiding the need to repeatedly query the DNS server for the same information.
What is the term used for the stored DNS information on a computer?
-The stored DNS information is called a DNS Cache, which is kept in the computer's memory to save time in searching.
How does the browser handle subsequent visits to the same website?
-For subsequent visits to the same website, the browser first checks the local DNS cache. If the IP address is not found in the cache, it then sends a request to the DNS server.
How does the DNS cache improve internet access speed?
-The DNS cache improves internet access speed by reducing the number of DNS requests sent to servers, thus speeding up the process of loading websites.
What is the relationship between DNS cache and internet efficiency?
-The DNS cache contributes to internet efficiency by storing domain-to-IP mappings, which reduces the time and resources needed for each website visit.
What is the technical term for the cache in English?
-The technical term for cache in English is 'cache', which refers to a resource in our fast memory that saves us time in searching.
How does the browser know to check the DNS cache before sending a DNS request?
-The browser is programmed to automatically check the DNS cache before sending a DNS request to ensure efficiency and speed in accessing websites.
Why is the DNS cache considered valuable, even though it doesn't make us rich?
-The DNS cache is considered valuable because it makes internet access faster and more efficient, which is a form of wealth in terms of time and resource savings.

Outlines

00:00

💻 DNS Cache Explained

This paragraph explains the concept of a DNS cache, which is a hidden treasure trove of information about websites you've visited stored in your computer. It clarifies that this cache improves internet access speed by reducing the number of DNS requests sent to servers. When you visit a website for the first time, your browser sends a DNS request, and the DNS server responds with the appropriate IP address. Subsequent visits to the same site are faster because the browser checks its local DNS cache before sending a request to the DNS server. This cache is a valuable resource that makes internet navigation quicker and more efficient.

Mindmap

Keywords

💡Cache

A cache is a high-speed data storage layer which saves copies of frequently accessed data to improve performance. In the context of the video, the term refers to the DNS Cache, which stores domain name to IP address mappings to speed up web browsing by reducing the need to repeatedly query DNS servers for the same information.

💡DNS (Domain Name System)

DNS is the system that translates human-friendly domain names into IP addresses that computers use to identify each other on the network. The script mentions DNS to explain how it is queried the first time a user visits a website, and how subsequent visits are faster due to the use of the DNS Cache.

💡IP Address

An IP address is a unique identifier for devices on a network. The video script discusses how the DNS server responds with an appropriate IP address when a browser sends a DNS request for a domain name, which is crucial for locating and accessing websites.

💡Browser

A browser is a software application for accessing information on the World Wide Web. The script uses the term to describe the process of sending DNS requests when visiting a website for the first time and how the browser utilizes the DNS Cache for efficiency.

💡Website

A website is a collection of related web pages, including multimedia content, typically identified with a common domain name and published on at least one web server. The video script refers to websites as the destinations that users access, which involves the process of DNS resolution.

💡Internet

The Internet is the global system of interconnected computer networks that use the Internet protocol suite to communicate. The script mentions the Internet in the context of how the DNS Cache improves the speed and efficiency of accessing websites online.

💡Request

In the context of the script, a request refers to the action of the browser asking for information, such as a DNS request for a domain name's IP address. The efficiency of the Internet is affected by how quickly these requests are sent and responded to.

💡Response

A response is the answer or reaction to a request. In the script, it is used to describe the action of the DNS server sending back an IP address after receiving a DNS request from a browser.

💡Efficiency

Efficiency refers to the ability to do or achieve something without wasting materials, time, or energy. The video script highlights how the DNS Cache increases efficiency by reducing the number of DNS requests sent over the Internet.

💡Speed

Speed in the script refers to the rate at which data is transferred or processed, particularly the time it takes to load a website. The DNS Cache is presented as a way to increase the speed of accessing websites by minimizing the need for repeated DNS lookups.

💡Domain Name

A domain name is a human-readable string that represents an IP address and is used to access websites. The script explains that when a user types a domain name into a browser, the DNS Cache is checked to find the corresponding IP address, which is essential for navigating to the website.

Highlights

Every computer contains a cache.

Cache is not about improving the state of the computer but about storing information about websites visited.

When visiting a website for the first time, the browser sends a DNS request.

DNS server responds with a suitable IP address.

On subsequent visits, the browser checks the DNS cache to speed up access.

Browsers save DNS requests in a local cache to reduce load time.

DNS Cache is a resource in our fast memory that saves us time searching.

When a website is visited, a record including the domain name and IP address is stored in the DNS Cache.

The computer first checks the local DNS cache before sending a request to the DNS server.

Cache does not make us rich but makes internet access fast and efficient.

Cache is also considered a treasure.