2048bit

2048bit is a term used to denote a data size of 2048 bits (256 bytes). In computing, the phrase is typically used as shorthand for the length of a cryptographic key or modulus, rather than a standalone data type.

In public-key cryptography, 2048-bit commonly refers to an RSA key modulus of 2048 bits. The modulus is the product of two primes; describing keys by bit length communicates the intended security level and compatibility. 2048-bit keys have long been a baseline for many protocols; larger sizes such as 3072 or 4096 bits are used for higher security settings.

Standards and practice: TLS/SSL, SSH and PGP widely support 2048-bit RSA keys. Many standards organizations recommended 2048-bit as a minimum since the 2010s; some agencies and providers now prefer 3072-bit for longer-term security.

Security considerations: The security of 2048-bit RSA relies on the difficulty of factoring large integers; progress in factoring algorithms or quantum computing would affect its strength. In current estimates, a 2048-bit RSA key provides roughly 112 bits of security against classical attacks. It is not resistant to quantum attacks; with a large-scale quantum computer, Shor’s algorithm would render such keys dramatically weaker, motivating migration to larger keys or post-quantum schemes.

Limitations and alternatives: 2048-bit RSA is computationally heavier for key generation, signing and verification and larger in message sizes for TLS handshakes compared with smaller keys but faster operations with modern hardware. Symmetric-key algorithms do not use 2048-bit keys; when symmetric strength is required, 128-, 192-, or 256-bit keys are used.