Quantum Cryptography Essay -- Codes Cryptography Symbols Essays

Quantum Cryptography Keeping secrets and passing information that is undetected has long been the goal of cryptographers. Codes have been written and then broken keeping cryptographers in constant search for the unbreakable code. Until recently, that goal seemed unreachable; however, a solution to the once impossible question seems to have surfaced. Quantum cryptography delves down into the world of very small particles, where there are entirely new ways of building ciphers. ("Arrives" 2) Quantum cryptography is a relatively recent discovery in the world of cryptography and is still being tested by the government for distance and practicality. Most recently, researchers at government-owned QinetiQ PLC and Ludwig-Maximilans-University demonstrated a nighttime key exchange using quantum cryptography over 23.4 km between the mountaintops at Zugspitze and Karwendelspitze in Germany (Bains 1). To understand how quantum cryptography works, one must first be familiar with the Heisenberg uncertainty principle. According to Heisenberg, when one tries to measure a quantum particle (a very small particle), the particle is altered in such a way that your measurement cannot be completely accurate. The particle is disturbed and its appearance before the attempted measurement can no longer be determined. ("Arrives" 3). In quantum cryptography, there are four different particles. The particles are identified by their positions: – (horizontal); | (vertical); / (left diagonal); \ (right diagonal). The particles are measured by the receiver with a filter, and predictably, the vertical filter allows vertical particles through, the horizontal filter allows horizontal particles through, and so on. Here, the Heisenberg uncertainty principle thro... ...he key that Bob is using, Alice is free to read any message Bob sends; however, Bob will be at a loss to decipher anything that Alice sends his way. While it is virtually impossible to eavesdrop using quantum cryptography, the system is only as reliable as the sender and the recipient. Works Cited "Special Report: Quantum Cryptography Arrives." PC Magazine. 6 pages. 6 August 2002. Article A90181639 (Infotrac). Bains, Sunny. "Alice and Bob grow apart. (Quantum Cryptography)." Laser Focus World. 2 pages. May 2002. v. 38. i.5. Article A86506297 (Infotrac). "The end of the code war? Quantum cryptography; The uncertainty principle and codes. (Science and Technology)." The Economist (US). 3 pages. 23 June 2001. Article A75710312 (Infotrac). Peterson, Ivars. "Quantum Cheating." Science News. 2 pages. 14 June 1997. v.151i. 24. Article A19524070 (Infotrac).