The Solaris Pseudo-Random Number Generator (PRNG) is available through the /dev/random and /dev/urandom devices. PRNG provides ISVs with a standard interface to access pseudo-random numbers for cryptographic operations, scientific applications, and simulation tools. The PRNG operates in the Solaris kernel. PRNG protects the contents of the entropy pool. The PRNG gathers entropic data from kernel memory pages and maintains a high level of randomness at all times.
For further information, see the random(7D) man page.