AEAD
Definition
Authenticated Encryption with Associated Data. Combines confidentiality and integrity in one primitive. AES-GCM and ChaCha20-Poly1305 are the two modern standards. TLS 1.3 allows only AEAD modes.
- Full form
- Authenticated Encryption with Associated Data
- Modern standards
- AES-GCM, ChaCha20-Poly1305
- Guarantees
- Confidentiality and integrity together
- TLS 1.3 rule
- Only AEAD modes permitted
Common questions
What problem did AEAD solve that older encrypt-then-MAC schemes did not?+
Combining encryption and authentication into one primitive removes the risk of implementers pairing the two incorrectly, a mistake that produced real vulnerabilities such as padding-oracle attacks in earlier protocol versions.
What is the associated data part actually for?+
It lets fields like a packet header stay unencrypted but still be covered by the integrity check, so the header can be routed or read in the clear while any tampering with it still causes authentication to fail.
Related terms
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- Mode of Operation
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- Stream Cipher
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