the key of DES

[Kim Yoonjeong]

Hello, all !
With given a unknown DES system with 64 bits plaintext p, ciphertext c,
can there be MORE THAN ONE keys ? 
If so, How is the probability (big or small)? 

	Sincerely, 
	 - Yoonejong 

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 Yoonjeong Kim 				Email: yjkim at ssrnet.snu.ac.kr
 Department of Computer Engineering	Phone: +82-2-875-7726 (office)
 Seoul National University		       +82-2-872-9801 (home)	
 Seoul 151-742 Korea			Fax:   +82-2-875-7726
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