17 Dec
2003
17 Dec
'03
11:17 p.m.
A couple years ago I found an obvious application of Diffie-Hellman which avoids this problem; unfortunately it turned out to be patented by someone from Siemens (first as a German patent and then a US patent, so it's definitely too much trouble to try to overturn the patent...) The basic approach is to use a commutative hash function, which lets both sides calculate HA(B) == HB(A) ; modular exponentiation worked fine.
Any chance that you're willing to discuss this further? -- Jim Thompson / Smallworks, Inc. / jim@smallworks.com 512 338 0619 phone / 512 338 0625 fax The Internet is Microsoft's Vietnam...