Sourav Sengupta’s Post

I’m shocked at how often this one question is asked in technical interviews everywhere (Amazon, Microsoft, Google & FAANG+ companies). What happens when you type a URL into your browser? Here’s how I would answer it: 1. Browser parses the URL      - The browser identifies the components: scheme (https), domain (example. com), and path (/hello-world).  2. DNS lookup      - The browser checks its cache or queries a DNS resolver (ISP or public DNS like Google’s 8.8.8.8) to translate the domain name into an IP address.      - If not cached, the resolver performs a recursive DNS lookup, contacting root, TLD, and authoritative name servers. 3. Establishing a connection      - A TCP connection is initiated between the browser and the server at the resolved IP address.      - If the URL uses HTTPS, a TLS handshake is performed to encrypt the connection. 4. Sending the HTTP request      - The browser sends an HTTP request with details like method (GET/POST), headers (e.g., User-Agent), and optional body data.      - Example: GET /hello-world HTTP/1.1.  5. Server processes the request      - The server identifies the resource from the request path and processes it.      - For dynamic content, the server might query a database, run application logic, and generate the response on the fly. 6. Returning the response      - The server responds with:        - Status Line: Indicates success or failure (e.g., 200 OK, 404 Not Found).        - Headers: Metadata like Content-Type (e.g., text/html) and caching instructions.        - Body: The requested content (e.g., HTML, JSON, or image data). 7. Browser renders the content      - The browser parses the HTML and makes additional requests for linked resources (e.g., CSS, JS, images).      - Resources are rendered progressively, and JavaScript is executed to enhance interactivity.  8. Caching and Optimization      - Browsers cache resources based on headers like Cache-Control.      - CDNs (Content Delivery Networks) and edge servers may serve static content to reduce latency.   Key Points for additional benefit: - Mention DNS caching at various layers (browser, OS, ISP).   - Highlight the TLS handshake and its role in securing HTTPS connections.   - Discuss CDNs and how they improve performance.   - Touch on asynchronous resource loading (e.g., defer or async for scripts).   - Bring up response codes and their significance (e.g., '200', '301', '503').  References for answer in the comments below.

I’m shocked at how often this one question is asked in technical interviews everywhere (Amazon, Microsoft, Google & FAANG+ companies). What happens when you type a URL into your browser? Here’s how I would answer it: 1. Browser parses the URL      - The browser identifies the components: scheme (https), domain (example. com), and path (/hello-world).  2. DNS lookup      - The browser checks its cache or queries a DNS resolver (ISP or public DNS like Google’s 8.8.8.8) to translate the domain name into an IP address.      - If not cached, the resolver performs a recursive DNS lookup, contacting root, TLD, and authoritative name servers. 3. Establishing a connection      - A TCP connection is initiated between the browser and the server at the resolved IP address.      - If the URL uses HTTPS, a TLS handshake is performed to encrypt the connection. 4. Sending the HTTP request      - The browser sends an HTTP request with details like method (GET/POST), headers (e.g., User-Agent), and optional body data.      - Example: GET /hello-world HTTP/1.1.  5. Server processes the request      - The server identifies the resource from the request path and processes it.      - For dynamic content, the server might query a database, run application logic, and generate the response on the fly. 6. Returning the response      - The server responds with:        - Status Line: Indicates success or failure (e.g., 200 OK, 404 Not Found).        - Headers: Metadata like Content-Type (e.g., text/html) and caching instructions.        - Body: The requested content (e.g., HTML, JSON, or image data). 7. Browser renders the content      - The browser parses the HTML and makes additional requests for linked resources (e.g., CSS, JS, images).      - Resources are rendered progressively, and JavaScript is executed to enhance interactivity.  8. Caching and Optimization      - Browsers cache resources based on headers like Cache-Control.      - CDNs (Content Delivery Networks) and edge servers may serve static content to reduce latency.   Key Points for additional benefit: - Mention DNS caching at various layers (browser, OS, ISP).   - Highlight the TLS handshake and its role in securing HTTPS connections.   - Discuss CDNs and how they improve performance.   - Touch on asynchronous resource loading (e.g., defer or async for scripts).   - Bring up response codes and their significance (e.g., '200', '301', '503').

𝐓𝐨𝐝𝐚𝐲'𝐬 𝐅𝐫𝐢𝐝𝐚𝐲 𝐅𝐞𝐞𝐥 𝐅𝐫𝐞𝐞 𝐃𝐚𝐲 If you really wanna make your site super fast. Then must know about 𝐖𝐡𝐚𝐭 𝐢𝐬 𝐜𝐚𝐜𝐡𝐞 𝐚𝐧𝐝 𝐡𝐨𝐰 𝐢𝐭 𝐰𝐨𝐫𝐤𝐬? Cache: In computing, a cache is a high-speed data storage layer which stores a subset of data, typically transient in nature, so that future requests for that data are served up faster than is possible by accessing the data's primary storage location So that means : There's 3 major types of cache. 1. Browser Cache. 2. page cache. 3. Object cache + Database Cache or Server Level Cache. 1. For browser cache: To shorten page load times, browsers cache most of the content that appears on the webpage, saving a copy of the webpage's content on the device's hard drive. This way, the next time the user loads the page, most of the content is already stored locally and the page will load much more quickly. It is on your chrome or whatever the browser you are using. 2. Page cache-CDN Cache: DNS caching permits a server or client to store DNS records locally and utilize them again in the future if necessary. To accomplish this, a time-to-live (TTL) value is used for each DNS record. This value specifies for how long (in seconds) a DNS client or server can cache a record. Different applications have different policies for caching DNS data. For example, Chrome caches up to 1,000 records for one minute. Steps: 1. A user enters a website URL (like www(.)example(.)com) in the browser. 2. The computer looks up the IP address for that website using a DNS server. 3. The DNS server checks its cache to see if it already has the IP address. 4. If the cache doesn’t have the IP address, the DNS server asks other “authoritative name servers” to help find the IP address. 5. The authoritative name servers respond with the IP address and a time-to-live (TTL) value that indicates how long the DNS record should be cached. 6. The DNS server caches the IP address and TTL value for a certain time based on its settings and the TTL value provided by the authoritative name server. 7. When the DNS record expires, the DNS server will query the authoritative name server again to get the updated IP address and TTL value. This helps to enhance the speed of website loading. After caching you will improve server response time and client response time. it will make an impact on your speed. 3. Object cache: Object caching involves storing database query results so that the next time a result is needed, it can be served from the cache without having to repeatedly query the database. Persistent object caching is a must if you’re looking to scale. Without it, your site’s performance will slow down as its complexity and traffic increase. Collected data about caching from different sources. Follow Muhammad Bilal for more seo tips and tricks.

Google #bigquery, You can now (GA) use #Terraform to manage IAM tags on #datasets and tables #security #dataclassification #tags #GeneralAvailability #GCP For details refer below -

Deciphering the Journey from Browser to Server: The Web Request Adventure Introduction Ever pondered what happens between pressing Enter after typing a URL in your browser and seeing your desired webpage? This intricate procedure unfolds through a series of carefully coordinated steps, tasked with fetching and presenting the webpage. Let's dissect the stages involved in this digital odyssey from the initial DNS query to the webpage's ultimate display. 1. Initiating the Quest with DNS The adventure kicks off with the input of a URL, like https://www.google.com, into your browser. The critical first step is conducting a DNS (Domain Name System) look-up. This entails your browser requesting a DNS server to pinpoint the IP address linked to “www.google.com.” Upon retrieving the correct IP address from the DNS server, your browser advances to the subsequent phase. 2. Establishing a TCP/IP Connection Armed with the IP address, your browser sets out to create a TCP (Transmission Control Protocol) connection to the server, specifying the IP and a port number (port 443 for HTTPS websites). TCP plays a vital role, ensuring a dependable channel between your browser and the server, segmenting the data into packets, and confirming their orderly receipt. 3. The Firewall Gateway Before establishing a TCP connection, the data packets may encounter a firewall. This serves as a cybersecurity sentinel for your system, inspecting packets against established security norms before they proceed to the server. 4. Securing with HTTPS/SSL Upon a successful TCP connection—and for sites employing HTTPS—the browser and server engage in securing the connection via SSL/TLS (Secure Sockets Layer/Transport Layer Security) protocols. This step is pivotal for encrypting the data exchange, safeguarding it from external threats. 5. The Role of Load-Balancers Major websites, such as Google, utilize multiple servers to handle requests. Here, a load-balancer elegantly distributes incoming requests among various servers. This ensures balanced performance and availability, avoiding server overloads. 6. The Application Server Interface Occasionally, a web server communicates with an application server to fulfill the request. Application servers are responsible for executing application logic, managing database queries, and generating dynamic content. Notable examples include Tomcat for Java applications and Django for Python platforms. 7. Database Interaction Should the request necessitate data stored in a database, the application server queries the database to retrieve essential information. Database servers like MySQL, PostgreSQL, or MongoDB supply the requested data to the application server, facilitating continuous request processing. In conclusion, a mere click or tap to view a webpage initiates an elaborate and intriguing process from your browser to the server. This journey incorporates DNS lookups, secure connections, and load balancing to deliver the final webpage.

Some useful status code that every developer should know Common HTTP Status Codes Status Code 200 – This is the standard “OK” status code for a successful HTTP request. The response that is returned is dependent on the request. For example, for a GET request, the response will be included in the message body. For a PUT/POST request, the response will include the resource that contains the result of the action. Status Code 201 – This is the status code that confirms that the request was successful and, as a result, a new resource was created. Typically, this is the status code that is sent after a POST/PUT request. Status Code 204 – This status code confirms that the server has fulfilled the request but does not need to return information. Examples of this status code include delete requests or if a request was sent via a form and the response should not cause the form to be refreshed or for a new page to load. Status Code 304 – The is status code used for browser caching. If the response has not been modified, the client/user can continue to use the same response/cached version. For example, a browser can request if a resource has been modified since a specific time. If it hasn’t, the status code 304 is sent. If it has been modified, a status code 200 is sent, along with the resource. Status Code 400 – The server cannot understand and process a request due to a client error. Missing data, domain validation, and invalid formatting are some examples that cause the status code 400 to be sent. Status Code 401 – This status code request occurs when authentication is required but has failed or not been provided. Status Code 403 – Very similar to status code 401, a status code 403 happens when a valid request was sent, but the server refuses to accept it. This happens if a client/user requires the necessary permission or they may need an account to access the resource. Unlike a status code 401, authentication will not apply here. Status Code 404 – The most common status code the average user will see. A status code 404 occurs when the request is valid, but the resource cannot be found on the server. Even though these are grouped in the Client Errors “bucket,” they are often due to improper URL redirection. Status Code 409 – A status code 409 is sent when a request conflicts with the current state of the resource. This is usually an issue with simultaneous updates, or versions, that conflict with one another. Status Code 410 – Resource requested is no longer available and will not be available again. Learn about network error 410. Status Code 500 – Another one of the more commonly seen status codes by users, the 500 series codes are similar to the 400 series codes in that they are true error codes. The status code 500 happens when the server cannot fulfill a request due to an unexpected issue. Web developers typically have to comb through the server logs to determine where the exact issue is coming from.

Do you know how many APIs your enterprise has? The use of APIs is extremely common in modern application services, as they facilitate integration, data exchange, and data updates. As a result, it is projected that by 2031, the global number of APIs in use will exceed 1 billion. However, before protecting these APIs, the primary task is to inventory and manage all of them clearly. Otherwise, any unmanaged 'shadow APIs' could provide malicious attackers with opportunities. Furthermore, these malicious attackers have found that APIs are often easier targets for attacks than the application services themselves. According to analysis, 90% of web-based network attacks target API endpoints. Unmanaged APIs are particularly exposed to high-risk environments because you cannot protect what you cannot see. ----- 你知道你的企業有多少個 API 嗎? API 的使用在現代應用服務中非常普遍，因為它們可以讓服務整合、數據交換或資料更新變得更加容易方便，也因此預計到2031年，全球使用的 API 數量將超過10億個。 然而，在保護這些 API 之前，首要任務是必須要把所有的 API 都盤點管控清楚，否則一但有未受管理的「影子 API」就會讓惡意攻擊者有可乘之機。 而且，這些惡意攻擊者已經發現 API 通常比應用服務本身更容易成為攻擊的破口，根據的分析，90% 的基於 Web 的網路攻擊目標是 API 端點。未受管理的 API 更是曝露在高風險的環境中，因為你無法保護你看不到的東西。 💡想要保護 AWS 上的 API 就找極風！ https://lnkd.in/giauBTX6 追蹤極風雲創，你的資安神隊友 ☁️ ✨ 如您希望了解更多，歡迎您與我們聯繫： https://lnkd.in/ghTCHEzF #極風雲創 #twister5 #資安 ＃API #F5

Have you ever wondered what happens behind the scenes when you type a URL like https://www.google.com into your browser and press Enter? Join me on a journey through the intricate layers of the web stack as we unravel the fascinating process of transforming a URL into a fully-rendered webpage. - DNS Request The journey begins with a Domain Name System (DNS) request. Your browser queries DNS servers to translate the human-readable domain name (e.g., www.google.com) into an IP address, allowing it to locate the corresponding web server. - TCP/IP With the IP address in hand, your browser establishes a Transmission Control Protocol (TCP) connection to the web server using the Internet Protocol (IP). TCP ensures reliable data transmission by breaking information into packets and confirming their delivery. - Firewall Before reaching the web server, the request may encounter a firewall, a barrier designed to monitor and control incoming and outgoing network traffic. The firewall evaluates the request based on predefined security rules, allowing legitimate traffic to pass through while blocking malicious or unauthorized attempts. - HTTPS/SSL As security becomes paramount, many websites utilize Hypertext Transfer Protocol Secure (HTTPS) with Secure Sockets Layer (SSL) or its successor, Transport Layer Security (TLS). This encryption protocol secures data transmission between the browser and the server, protecting against eavesdropping and tampering. - Load Balancer Upon reaching the server infrastructure, a load balancer may come into play, distributing incoming requests across multiple servers to optimize resource utilization and maintain high availability. This ensures that no single server becomes overwhelmed, enhancing scalability and resilience. - Web Server The web server receives the request, processes it, and retrieves the requested resources, such as HTML, CSS, and JavaScript files. Common web servers include Apache, Nginx, and Microsoft Internet Information Services (IIS), each with its own strengths and configuration options. - Application Server In dynamic web applications, an application server may handle business logic, database queries, and other server-side operations. Technologies like Node.js, Django, and Ruby on Rails empower developers to build robust and responsive web experiences. - Database Many web applications rely on databases to store and retrieve data efficiently. From traditional relational databases like MySQL and PostgreSQL to NoSQL databases like MongoDB and Redis, the choice depends on the specific requirements of the application and its scalability needs. By understanding the intricacies of this workflow, software engineers gain valuable insights into the functioning of the web stack, paving the way for more informed decision-making and efficient troubleshooting. Whether you're a front-end developer or a backend engineer, this knowledge proves beneficial in creating optimized web solutions.

Google #CloudSpanner is expanding its ability to natively interact with JSON documents. Check out the new functions in the link below. The syntax is the same as #BigQuery making it easy to work with the two - federated! - platforms. Try them now: ⬇️⬇️ https://lnkd.in/dbc4X_mV