Re: [time-nuts] When NTP goes wrong...
Mark Sims said: > Ars Technica just put up a piece on the effects of various attacks on NTP > with a link to the original paper. > > http://arstechnica.com/security/2015/10/new-attacks-on-network-time-protocol-can-defeat-https-and-create-chaos/ The Network Time Foundation (through Harlan Stenn’s hard work) has already released a patch synchronized with the publication of the referenced paper from Boston University: http://nwtime.org/ntf-releases-ntp-security-patches-ntp-4-2-8p4/ Many of the comments on the Ars Technica piece are quite naive regarding timekeeping issues. This reflects an ongoing need for public education that Time-nuts as well as NTF can help supply. Rob Seaman ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] GPS Disciplined TCXO
There were some postings on the list for this over the summer. I think he was going to sell them on Tindie. On 10/20/2015 16:53, Bryan _ wrote: Saw this on the Hackaday site if anyone is interested. https://hackaday.io/project/6872-gps-disciplined-tcxo -=Bryan=- ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] GPS Disciplined TCXO
Thanks. That’s me. I posted a while ago here, but I’ve made a great deal of progress since then. I’ve logged most of what I’ve discovered and learned on the project itself. I believe I now have reasonable confidence in the performance of the two models. I’d be happy to share my methodology so that others could attempt to duplicate or verify my results. It’s going to remain an open source / open hardware project, but I do sell them in my Tindie store too. > On Oct 20, 2015, at 1:53 PM, Bryan _ wrote: > > Saw this on the Hackaday site if anyone is interested. > https://hackaday.io/project/6872-gps-disciplined-tcxo > > -=Bryan=- > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] When NTP goes wrong...
Ars Technica just put up a piece on the effects of various attacks on NTP with a link to the original paper. http://arstechnica.com/security/2015/10/new-attacks-on-network-time-protocol-can-defeat-https-and-create-chaos/ Also, I was looking at my firewall last week and it showed over 10,000 attempts to hack NTPD over a period of a couple of days. I usually only see a couple of dozen... somethings afoot out there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] "Selective availability" af accurate time for Apple users?
I think it has to do more with battery life as the first release of iOS 9 drained battery faster than prior releases and the GPS is expensive from a power standpoint. I think the non watch devices sacrificed precision time for runtime Content by Scott Typos by Siri > On Oct 20, 2015, at 12:09 PM, Paul wrote: > > On Tue, Oct 20, 2015 at 4:02 AM, Brian Garrett > wrote: >> ... As measured by NTP apps such as Emerald Time and Watchville, > millisecond accuracy comparable to the soon-to-be-released Apple Watch was > now commonplace, with typical offsets of 5 ms or less, rather than the > several seconds of offset typical under the previous release. > > Network connected iOS devices not paired with a watch use (s)ntp at large > intervals rather than the mobile network or GPS. The offsets appear to be > somewhat random -- both positive and negative, large (s) and small (ms). I > assume it's related to the environment and the last time the offset was > corrected. > >> Now, with the latest version, iOS 9, the Apple Watch level accuracy > previously available to iPhone users has gone away. Once again, your > iPhone will be as much as several seconds slow as measured by NTP, unless > you force an update to the phone’s clock by opening a GPS app. > > I checked on an iPad (but presumably that shouldn't matter). My current > offset is -1.6 s (fast, and slowly increasing) as measured by Time > independent of GPS which I woke with Observatory which uses both NTP (for > time) and the GPS (for location). Restarting the iPad causes a step. This > compares with +1 to -3 ms on my phone. > > I'll admit the above is slightly speculative because I haven't checked > network traffic yet but I will shortly. > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] HP Type II feet.
List, I'd like to buy up to 60 HP type II feet. I don't need the metal bail but it would be OK to have also. Please reply off list with amount and price. I also have some TN HP test equipment that could be used in a trade/cash deal. Regards, Perrier ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] GPS Disciplined TCXO
Saw this on the Hackaday site if anyone is interested. https://hackaday.io/project/6872-gps-disciplined-tcxo -=Bryan=- ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] "Selective availability" af accurate time for Appleusers?
Warning: the following may be apocryphal. I was once told: Sprint PCS networks distributed very accurate time to cell phones because GPSDO & accurate time was essential to the multiplexing technology then in use. In contrast, time of day at an AT&T GSM cell site depending on the accuracy of the technician’s watch when setting up the site. Hence, each site could be many seconds different from its neighbors. I have never verified this information, and it is 10 years old. > On 2015 Oct 21, at 01:41 , David J Taylor > wrote: > > Has anybody else observed this with their iPhone since “upgrading” to iOS 9? > Anyone know of any difference in the reference time ( e.g. GPS vs. network > time) that Apple is using to “dumb down’ their smartphones in favor of Apple > Watch? > > Brian Garrett > > > Yes, on one quick check, I now see an accuracy (or rather error) o my iPad of > up to several seconds (iOS 9.0.2) compared to my recollection of sub-second > accuracy under iOS 8.0.2x. > > My £50 Windows 10 tablet using real NTP does /much/ better! > > Cheers, > David > -- > SatSignal Software - Quality software written to your requirements > Web: http://www.satsignal.eu > Email: david-tay...@blueyonder.co.uk > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. signature.asc Description: Message signed with OpenPGP using GPGMail ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] HP5065A fs
Hi all, I have an HP5065A for sale. It mount the option 01 digital clock. The unit is refurbished and tested. Capacitors and diodes upgraded. upgrade info: http://www.timeok.it/wp/wp-content/uploads/2015/09/First-aid-when-you-buy-an-hp5065A-v-1.2.pdf No power cable. I ask 1250.oo Euros. Shipping within Europe around 120Euro, may be less, to be verified. Pictures available on request. If interested email me directly: tim...@timeok.it thank you, Luciano Message sent via Atmail Open - http://atmail.org/ ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Seismic station timing in Australia during the late 1970's
At the Seismic Station in central Australia that I ran from 1974 to 1980 we had a free running 5MHz xtal oven in our Station clock. The clock was powered from one of our 600AHr 24VDC battery banks (UPS) and it was 'synced' to VNG http://www.ontheshortwaves.com/VNG.html (the Oz equivalent to WWV) via an HF radio. The 1pps output from the clock was used to start the time base scan on an oscilloscope and the audio from VNG was displayed on channel 1, the clock had an adjustable divider chain that allowed the 1pps to be advanced or retarded. The clock would 'normally be retarded until the start of the VNG tone was just visible on the LHS of the scope trace. The operator would check for the right second by listening for the 'long' tone at the top of the minute.http://tufi.alphalink.com.au/time/nsc_vng_leaflet.pdf Time was set each morning after 00UT, 9:30 local time. Accuracy, anyone's guess but the offset was fairly constant day to day. The operator would record the drift that was corrected in the station's log each morning. An estimation of the propagation delay from the transmitter to our site was taken into account when analysing the records. The xtal oven was adjusted for a drift (fast) of a few mS for the day, this ensured that the scope was triggered before the time signal was received , making it easier for the operator to check and measure the daily drift. IRIG H (slow code) time code was generated by the clock and sent to helicorders (waxed paper chart recorders) and low speed 0.3ips 24 channel FM tape recorders. Various schemes were tried for syncing portable recorders and remote calibration circuits. Omega was one and the sun shining through a lens and a thin slit made from 2 razor blades onto a photocell was another. The best however was a cheap AM receiver tuned to the local National Radio station (ABC) who would (remotely) turn on their transmitters across outback Australia at the same time (6am) every morning. The carrier was detected and the portable recorders clocks 'synced'. This worked very well when we got ours for about 2 weeks until the national radio station went 24hrs! No one had bothered to talk to them. Ah, the days before GPS were so much simpler. Blair Lade Australia --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] "Selective availability" af accurate time for Appleusers?
Has anybody else observed this with their iPhone since “upgrading” to iOS 9? Anyone know of any difference in the reference time ( e.g. GPS vs. network time) that Apple is using to “dumb down’ their smartphones in favor of Apple Watch? Brian Garrett Yes, on one quick check, I now see an accuracy (or rather error) o my iPad of up to several seconds (iOS 9.0.2) compared to my recollection of sub-second accuracy under iOS 8.0.2x. My £50 Windows 10 tablet using real NTP does /much/ better! Cheers, David -- SatSignal Software - Quality software written to your requirements Web: http://www.satsignal.eu Email: david-tay...@blueyonder.co.uk ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
