[PLUG] Reading computer time stamp over internet

Alex Daniloff alex at daniloff.com
Wed Mar 22 01:00:11 UTC 2006


I'm not talking about NTP but plain browser and a server interaction.
I'm asking about any mechanism which can be used on the server side to 
retrieve timestamp from the client browser without using javascript.

Thanks,

Alex

On Tuesday March 21 2006 16:12, Tim Thorpe wrote:
> I think what you are asking for is NTP but I'm not sure, NTP stands for
> Network Time Protocol. It's a dedicated protocol for clock syncing. beyond
> that I haven't looked too much in to it I know I use it but I don't know
> the nitty gritty details of how it works or how to configure it in linux. I
> do know my linux box sets it's time via NTP every time it starts up, and I
> know you can cron-job it somehow to update the clock at regular intervals
> to keep it on time. but the how to do it escapes me. perhaps someone else
> on the list can help us.
>
> On 3/21/06, Alex Daniloff <alex at daniloff.com> wrote:
> > Thanks you all for the answers.
> > May be somebody can advise me how to retrieve client
> > browser or PC timestamp on the server side without
> > using java or javascript.
> >
> > Thanks,
> >
> > Alex
> >
> > On Tuesday March 21 2006 12:15, Steve Bonds wrote:
> > > On 3/21/06, Alex Daniloff alex-at-daniloff.com wrote:
> > > > I wonder, how they do this. Is it a part of TCP/IP protocol or
> > > > environmental variable of my browser?
> > >
> > > As others have noted, in this case it was just some javascript,
> > > however there are a number of other ways to get your PC's time-- the
> > > simplest is the TCP timestamp option which is enabled by default on
> > > all modern distros of Linux that I've seen:
> > >
> > > http://www.ietf.org/rfc/rfc1323.txt
> > >
> > > Another option would be the ICMP timestamp:
> > >
> > > http://www.networksorcery.com/enp/protocol/icmp/msg13.htm
> > >
> > > This is seldom used, but enabled by default on at least Red Hat
> > > variants-- I can't remember if it's enabled on others.
> > >
> > > I recall reading an article about "fingerprinting" PCs based on the
> > > delay patterns between packets to reveal the PC's inherent clock
> > > drift, but I can't find the URL.  However, I know of no current
> > > vulnerabilities that could be exploited using your PC time.  I
> > > generally don't worry too much about the fact that it's trivial to
> > > deduce my current PC time.
> > >
> > >   -- Steve
> > > _______________________________________________
> > > PLUG mailing list
> > > PLUG at lists.pdxlinux.org
> > > http://lists.pdxlinux.org/mailman/listinfo/plug
> >
> > _______________________________________________
> > PLUG mailing list
> > PLUG at lists.pdxlinux.org
> > http://lists.pdxlinux.org/mailman/listinfo/plug
>
> _______________________________________________
> PLUG mailing list
> PLUG at lists.pdxlinux.org
> http://lists.pdxlinux.org/mailman/listinfo/plug



More information about the PLUG mailing list