RE: Seeking assistance deciphering NTP packet capture
Bryan Evenson <[email protected]>
| Newsgroups | gmane.comp.time.chrony.user |
|---|---|
| Message-ID | <CY5PR20MB48203F3ED52B6A92E0702398BBA29@CY5PR20MB4820.namprd20.prod.outlook.com> |
Miroslav, > -----Original Message----- > From: Miroslav Lichvar <[email protected]> > Sent: Monday, June 6, 2022 4:05 AM > To: [email protected] > Subject: Re: [chrony-users] Seeking assistance deciphering NTP packet > capture > > On Fri, Jun 03, 2022 at 07:43:07PM +0000, Bryan Evenson wrote: > > March 20, 1985 7:17:35 UTC > > July 31, 2036 00:19:20 UTC > > July 25, 2004, 05:41:48 UTC > > Feb 16, 2061 19:03:36 UTC > > > > These were from packets send about one minute apart from each other. > On the server response, the Reference Timestamp, Receive Timestamp and > the Transmit Timestamp were all reasonably close to each other and were > based on current time. > > > > Does someone know why the transmit timestamps are so far off from > actual time? Is this just a data translation problem where Wireshark is > reading the field format incorrectly? > > The client's transmit timestamps are completely random. The server doesn't > need to know client's time. It's indicated by the precision of > 32 in the packet. It's a security and privacy feature described here: > > https://datatracker.ietf.org/doc/html/draft-ietf-ntp-data-minimization-04 Thanks for the information. That makes sense. I'm going to be suggesting some modifications to the automated test kit to account for this. Thanks, Bryan Evenson > > -- > Miroslav Lichvar > > > -- > To unsubscribe email chrony-users-request-kWFZVVI9zxvPqho9SqqRMmD2FQJk+8+b@public.gmane.org > with "unsubscribe" in the subject. > For help email chrony-users-request-kWFZVVI9zxvPqho9SqqRMmD2FQJk+8+b@public.gmane.org > with "help" in the subject. > Trouble? Email [email protected] -- To unsubscribe email chrony-users-request-kWFZVVI9zxvPqho9SqqRMmD2FQJk+8+b@public.gmane.org with "unsubscribe" in the subject. For help email chrony-users-request-kWFZVVI9zxvPqho9SqqRMmD2FQJk+8+b@public.gmane.org with "help" in the subject. Trouble? Email [email protected]