Triple DES (3DES)
What is Triple DES (3DES)?
Triple DES (3DES)A legacy block cipher that applies the DES algorithm three times with two or three keys to extend its key length; now retired by NIST and considered obsolete.
Triple DES (3DES, TDEA) was introduced to extend the life of DES by applying it three times to each 64-bit block in an Encrypt-Decrypt-Encrypt configuration, giving an effective key strength of 112 bits with two keys (2-key) or 168 bits with three independent keys (3-key). Although stronger than single DES, 3DES still uses a 64-bit block, which makes it vulnerable to birthday attacks like Sweet32 (2016) when large volumes of data are encrypted under the same key. NIST formally deprecated 3DES in SP 800-131A and disallowed its use after 2023, and TLS 1.3, PCI DSS, and modern protocols have already removed it. New systems should use AES-GCM or AES-CCM instead; 3DES persists only in legacy financial and embedded systems.
● Examples
- 01
Older EMV chip-and-PIN payment systems used 3DES for PIN encryption.
- 02
Cisco IPsec VPNs historically offered 3DES as a transitional algorithm.
● Frequently asked questions
What is Triple DES (3DES)?
A legacy block cipher that applies the DES algorithm three times with two or three keys to extend its key length; now retired by NIST and considered obsolete. It belongs to the Cryptography category of cybersecurity.
What does Triple DES (3DES) mean?
A legacy block cipher that applies the DES algorithm three times with two or three keys to extend its key length; now retired by NIST and considered obsolete.
How do you defend against Triple DES (3DES)?
Defences for Triple DES (3DES) typically combine technical controls and operational practices, as detailed in the full definition above.
What are other names for Triple DES (3DES)?
Common alternative names include: 3DES, TDES, TDEA.