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Flip to reveal answersWhat is the difference between symmetric and asymmetric cryptography?
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All 5 Flashcards — Encryption and certificates
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Question
What is the difference between symmetric and asymmetric cryptography?
Answer
Symmetric uses one key to both lock and unlock — fast, but the key must reach the other end safely. Asymmetric uses two matched keys: a public one anyone may have and a private one that never leaves, so nothing secret has to travel.
Question
Which key encrypts and which decrypts in asymmetric cryptography?
Answer
For confidentiality, the recipient's public key encrypts and only their matching private key can decrypt. That is why the public key can be handed to anyone without weakening anything.
Question
What is a digital certificate?
Answer
An organisation's public key together with its identity, signed by a certificate authority the browser already trusts. It proves the public key really belongs to who it claims, which a bare public key cannot.
Question
Why does HTTPS use both symmetric and asymmetric encryption?
Answer
Asymmetric solves the problem of agreeing a key safely but is slow. So it is used once to agree a symmetric key, and all the actual traffic is then encrypted symmetrically because that is much faster for bulk data.
Question
Why does key management matter as much as the encryption itself?
Answer
Keys must be generated properly, stored where nobody else can reach them, replaced periodically and revoked immediately if they leak. A private key that escapes makes every message ever sent with it readable, however strong the algorithm.
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Topic 2.4 hub
Network security
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