How do TCP and TLS relate to each other? What problem does TLS solve?
Middle+
228
Frontend
6300
681
If TLS encrypts traffic, but an attacker intercepts the packet and re-sends it to the server (replay attack) — why won't this work? What happens during the steps of establishing a TLS connection?
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212
What are the advantages and disadvantages of TypeScript compared to JavaScript?
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205
Evaluate the following authorization implementation: login/password form, backend searches for a user in the database (table: id, username, password), takes an integer ID and writes it into a cookie with HttpOnly flag. What's wrong with this implementation and how to fix it?
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171
How does React work under the hood? Explain the reconciliation mechanism, Virtual DOM, Fiber architecture, and why there are two phases (render and commit).
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166
HTTP is a protocol of which OSI model layer? What is underneath it?
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158
Describe what happens network-wise when a browser requests a page — for example, you enter a link in the address bar. Outline all steps from that moment until the HTML code is received.
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152
Provide an example of a poorly designed functional component that causes unnecessary re-renders, and explain how to fix it.
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144
What is React, why is it needed, and what tasks does it solve? When should you use React, and when is plain JavaScript enough?
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143
How to properly generate authorization tokens? What should be inside the token to protect against brute force?
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140
How is asymmetric encryption used within TLS and what is it for?
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134
What does an HTTP request consist of? Name its main parts and blocks.
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132
When using HTTPS, which parts of the HTTP request are encrypted and which remain open? For example, is the URL, headers, or request body encrypted?
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132
Besides IP address, what else is needed to open a TCP connection?
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121
How do sessions and authorization work? How do subsequent requests not require re-authorization after login?
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105
A user clicks the pay button for 100 rubles, a POST request is sent to the server, but no response is received — timeout. How to prevent double charging on retry? How is this handled on the frontend and architecture?
Middle+
93