If we calculate this value for each second, i.e., queries per second (QPS) = 500 million / (30 days * 24 hours * 3600 seconds) = ~200 URLs/s.Traffic Estimation: We can assume that we will have 500 million new URL shortening requests per month with a 100:1 read/write ratio, we can expect 50 billion redirections during the same period (100 * 500 million= 50 billion). Database- It will be used to store the mapping of long URLs to short URLs.Web Servers- Multiple instances of web servers will be deployed for horizontal scaling.Load Balancer- To distribute the load evenly among the backend servers.It will communicate with the backend servers via HTTP protocol. Here, we will assume that our read/write = 100 : 1 key componentsįollowing will be the key components in the URL shortening application: The most important thing to keep in mind here is that our system will be read-heavy, i.e., the number of reading requests per second can be up to 1000 times more than the writing request. This section will look at the estimate of the number of monthly requests, storage, etc. Users should be able to specify the expiration time of the URL.

Analytics: How many times the URL is visited?.The service should be REST API accessible.Shortened links should not be predictable in any manner.URL redirection should happen in real-time with minimal latency.Therefore, our system should be highly available. If the system fails, it will imply that all the short links will not function.Users should have the option to give a custom short link for their URL.The short link should redirect users to the original link.Users should be able to generate a shortened URL from the original URL.The URL shortening service like Tiny-URL should have the following features: This brings us to a discussion around the requirements and features of the system. Whenever the user visits the short URL, he/she will be redirected to the original URL.īefore jumping to the solution, as an interviewee, we should always discuss with the interviewer what he/she wants. Tiny-URL is a URL-shortening web service that creates shorter aliases for long URLs. The goal is to design a highly scalable service that could allow users to create shorter URLs, given long URLs, and have read and write functionality. Asked in: Google, Facebook, Amazon, Adobe Let’s understand the problemĭesign a URL Shortening service like Tiny-URL service.

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