>It is safer to use 3-DES than single Des because we use a 128-bit key
>instead of a 64-bit key, so the number of possible keys is much bigger.
Also
>it has been reported that a method called 'match in the middle' could
>penetrate the single -DES but not the 3-DES.
>
>-----Original Message-----
>From: Jeffrey Altman <[EMAIL PROTECTED]>
>To: Johan Danielsson <[EMAIL PROTECTED]>
>Cc: [EMAIL PROTECTED] <[EMAIL PROTECTED]>;
>[EMAIL PROTECTED] <[EMAIL PROTECTED]>
>Date: Tuesday, November 23, 1999 4:24 PM
>Subject: Re: Last Call: Telnet Authentication Option to Proposed Standard
>
>
>>> Jeffrey Altman <[EMAIL PROTECTED]> writes:
>>>
>>> > You are questioning the use of Triple DES but not the use of
>>> > CAST-128.
>>>
>>> I'm questioning the use of DES3 in anything but EDE on outer CBC
>>> mode. There is a paper by Eli Biham about other combinations, which
>>> basically says that most of them are not much better than single DES.
>>>
>>> Even though this paper doesn't talk about this specific use, it's not
>>> obvious that it's more secure to use DES3 to generate random numbers
>>> than it is to use single DES.
>>>
>>> Has this case been analysed by anyone?
>>>
>>> /Johan
>>>
>>
>>Thanks for explaining. The answer is that I don't know. I am not
>>qualified to make that analysis.
>>
>>
>> Jeffrey Altman * Sr.Software Designer * Kermit-95 for Win32 and OS/2
>> The Kermit Project * Columbia University
>> 612 West 115th St #716 * New York, NY * 10025
>> http://www.kermit-project.org/k95.html *
>[EMAIL PROTECTED]
>>
>>
>>
>
