DES

DES or diethylstilbestrol (dī'ĕth'əlstĭlbĕs`trôl), synthetic nonsteroid female sex hormone having the same physiological effects as estrogen. In the 1940s and 50s DES was mistakenly believed to reduce the risk of miscarriage and was routinely prescribed for pregnant women believed to be at risk. In fact, it was later found to increase the risk of miscarriage and was then tested in a "morning-after" pill, a contraceptive pill that is taken after intercourse. In the late 1960s and early 70s a group of Boston physicians found that women whose mothers had taken DES during pregnancy had an unusually high rate of vaginal cancer, and it has since been implicated in various reproductive disorders and other conditions in female and male children of such mothers. The use of DES to prevent miscarriage was banned in 1973; its use as a growth accelerator in beef cattle was banned in 1979. It currently finds some use in the hormone treatment of certain types of cancer.

---

DES

(1) (Digital Entertainment System) See digital media server.

(2) (Data Encryption Standard) A NIST-standard cryptographic cipher that uses a 56-bit key. Adopted by the NIST in 1977, it was replaced by AES in 2001 as the official standard. DES is a symmetric block cipher that processes 64-bit blocks in four different modes of operation, with the electronic code book (ECB) being the most popular.

Triple DES
By adding various multiple-pass methods, Triple DES increased security; for example, encrypting with one key, decrypting the results with a second key and encrypting it again with a third. However, the extra passes added considerable computing time to the process. DES is still used in applications that do not require the strongest security. See cipher, cryptography, NIST, AES and Fortezza.

---

DES

(communications)

data encryption standard

(biochemistry)

diethylstilbesterol

---

DES - Data Encryption Standard