Path: utzoo!attcan!uunet!cs.utexas.edu!tut.cis.ohio-state.edu!ucbvax!agate!shelby!CCC.MFECC.LLNL.GOV!NESSETT
From: NESSETT@CCC.MFECC.LLNL.GOV
Newsgroups: comp.protocols.kerberos
Subject: secure time synchronization
Message-ID: <890517131212.2900013d@CCC.MFECC.LLNL.GOV>
Date: 17 May 89 20:12:12 GMT
Sender: daemon@shelby.Stanford.EDU
Organization: The Internet
Lines: 10

Dave,

To solve the secure time synchronization problem, you will need more than an
authenticated time service.  It must not be possible to replay synchronization
messages thereby setting a local clock back by an arbitrary amount. Perhaps
the protocol you use prevents this.  We found that designing a secure
time synchronization protocol to be equivalent to designing a secure
connection protocol.

Dan