사용자토론:Ehlegeth/드래프트1

Auguste Kerkhoffs의 발음

아우구스트 케르크호프 아우후스트 케르크호프스 http://www.forvo.com/word/auguste_kerckhoffs/ Duch이므로 http://www.korean.go.kr/09_new/dic/rule/rule_foreign_0118.jsp

미번역

• Kerkhoffs's Principle의 번역 작업 중 미번역한 내용은 아래와 같다.

Applications

In accordance with Kerckhoffs's principle, the majority of civilian cryptography makes use of publicly known algorithms. By contrast, ciphers used to protect classified government or military information are often kept secret (see Type 1 encryption). However, it should not be assumed that government/military ciphers must be kept secret to maintain security. It's possible that they are intended to be as cryptographically sound as public algorithms, and the decision to keep them secret is in keeping with a layered security posture.

응용

커크호프 원리와 상응해서, 민간인 암호학의 대다수는 공개적으로 알려진 알고리즘을 사용한다. 반면에, 정부나 군대의 기밀 정보들을 보호하는데 사용되는 암호기는 흔히 비밀로 유지된다 (see Type 1 encryption). 그러나, 정부나 군대의 암호기가 보안을 유지하기 위해 비밀로 유지된다고 가정되어서는 안된다. It's possible that they are intended to be as cryptographically sound as public algorithms, and the decision to keep them secret is in keeping with a layered security posture.

Eric Raymond extends this principle in support of open source security software, saying, "Any security software design that doesn't assume the enemy possesses the source code is already untrustworthy; therefore, never trust closed source."

Implications for analysis

For purposes of analysing ciphers, Kerckhoffs's principle neatly divides any design into two components. The key can be assumed to be secret for purposes of analysis; in practice various measures are taken to protect it. Everything else is assumed to be knowable by the opponent, so everything except the key should be revealed to the analyst. Perhaps not all opponents know everything, but the analyst should because the goal is to create a system that is secure against any enemy except one that learns the key.

John Savard describes the widespread acceptance of this idea:

That the security of a cipher system should depend on the key and not the algorithm has become a truism in the computer era, and this one is the best-remembered of Kerckhoffs's dicta. ... Unlike a key, an algorithm can be studied and analyzed by experts to determine if it is likely to be secure. An algorithm that you have invented yourself and kept secret has not had the opportunity for such review.

Security through obscurity

 이 부분의 본문은 Security through obscurity입니다.

It is moderately common for companies and sometimes even standards bodies as in the case of the CSS encryption on DVDs – to keep the inner workings of a system secret. Some argue this "security by obscurity" makes the product safer and less vulnerable to attack. A counter argument is that keeping the innards secret may improve security in the short term, but in the long run only systems that have been published and analyzed should be trusted.

Steve Bellovin commented:

The subject of security through obscurity comes up frequently. I think

a lot of the debate happens because people misunderstand the issue.

It helps, I think, to go back to Kerckhoffs's second principle, translated as "The system must not require secrecy and can be stolen by the enemy without causing trouble," per http://petitcolas.net/fabien/kerckhoffs/). Kerckhoffs said neither "publish everything" nor "keep everything secret"; rather, he said that the system should still be secure *even if the enemy has a copy*.

In other words – design your system assuming that your opponents know it in detail. (A former official at NSA's National Computer Security Center told me that the standard assumption there was that serial number 1 of any new device was delivered to the Kremlin.) After that, though, there's nothing wrong with trying to keep it secret – it's another hurdle factor the enemy has to overcome. (One obstacle the British ran into when attacking the German Enigma system was simple: they didn't know the unkeyed mapping between keyboard keys and the input to the rotor array.) But – *don't rely

on secrecy*.

참고 문헌

인용 불가능

• ケルクホフスの原理
• Kerckhoffs’ Principle