RAMHU: A New Robust Lightweight Scheme for Mutual Users Authentication in Healthcare Applications

Table 1

Keys sizes and some information for asymmetric algorithms.

Algo.	Keys sizes					Ratio	Author(s)	Year	Mathematical problem
RSA	1024	2048	3072	7680	15360	1:6-30	Rivest, Shamir, and Adleman	1978	Integer factorization
Elgamal							Taher Elgamal	1985	Multiplicative group
ECIES	160-223	224-255	256-383	384-511	512-more		Neal Koblitz and Victor Miller	1985	Elliptic curve discrete log. (ECDLP)