2 expanded posts ยท every known parent and child
>It says that the commerce server supports (among others) DES and DES3 >(same as 3DES?). They list the key sizes as 64 and 192 bits >respectively. My question is, isn't DES 56 bits? (with an 8 bit salt >that would be 64 I guess), but isn't DES3 112 bits, not 192? DES keys are specified as 64 bits, of which 8 bits provide odd parity. The 192 bits would specify three independent keys (not triple DES)
Various people said: > >It says that the commerce server supports (among others) DES and DES3 > >(same as 3DES?). They list the key sizes as 64 and 192 bits > >respectively. My question is, isn't DES 56 bits? (with an 8 bit salt > >that would be 64 I guess), but isn't DES3 112 bits, not 192? > DES keys are specified as 64 bits, of which 8 bits provide odd parity. > The 192 bits would specify three independent keys (not triple DES) Real-world DES implementations ignore those 8 "parity" bits. DES uses 56 bits of key for encryption, and calling it a 64 bit key is misleading. Triple DES (3DES) is an overloaded term. It's used in 2- and 3-key versions, for 112 and 168 bits of protection respectively. Jim Gillogly Highday, 25 Wedmath S.R. 1995, 22:18