Re: time kepping using GPS
Thank you very much Mr de Raadt, for the very complete and insightful information regarding GPS & the interaction and actions of clocks with their signal, and loss thereof. On 3/20/2012 11:49 AM, Theo de Raadt wrote: >> some insights for people using GPS for very critical server time keeping >> http://www.dw.de/dw/article/0,,15817272,00.html > This misses the point in a rather large way. > > Most of this jamming makes the true GPS signal hard to receive. > > When the signal cannot be received, the existing free-running clocks > in various parts of the "system" keep working. Since the subsystem as > a whole has learned the 1st, 2nd, and hopefully 3rd and further > derivatives to tune itself and predicively pace, everything works out. > Until the GPS signal or whatever else comes back. > > Oh my god, sometimes we use net, and we can't talk to remote > Internet-based ntp services. Except that's the point -- we only pay > attention to the remote services (ntp or gps) to learn how to tune > various adjustments to the free-running clocks. > > Furthermore, some GPS receivers will keep feeding their own > free-running clocks but say the service is "degraded". It is not like > that free-running clock on the GPS is going to go wonky immediately. > > It is being jammed. It is not being spoofed. > > The end result is that the clock does not go crazy. It remains stable > and the best effort result is good enough. > > So enough of this "oh my god, it is all going to go wrong" balony.
Thanks Jacek Artymiak: Book PDF's
A huge Thanks to Jacek Artymiak for the PDF's of "Building Firewalls with OpenBSD and PF, 3rd ed." and "The OpenBSD Command-LineCompanion". The wait was worth it !!!
Re: Jacek books
On 2/14/2010 12:26 PM, open...@e-solutions.re wrote: Hello, I bought the books from http://www.devguide.net : "OpenBSD Command-Line Companion" and "Building OpenBSD Firewalls with OpenBSD 3th Ed" in PDF and Printed version (since september 2009) Is there someone that will have a copy of these books in pdf format ? I received NOTHING Thank you very much. I did the exact same thing, and I did receive 'snippets' of chapters in PDF format over a period of time, which I've compiled into one printed booklet, but I'd like to receive the book as a whole as was originally stated. I did use Pay Pal, so I do have a valid copy of my payment, shown below. I'm hardly sweating it though, as I've always known Jacek Artymiak to be a man of his word and an exceptional talent that I feel we're very fortunate to have as a developer. Please just give it some time. I've found it's always better to look very closely and very long before leaping to any conclusions. Regards, WED == Business Name: devGuide.net (The recipient of this payment is Non-U.S. - Verified) Email: sa...@devguide.net Payment Sent to: ja...@devguide.net Total Amount: -b,47.00 EUR Fee amount: b,0.00 EUR Net amount: -b,47.00 EUR (equals -$62.21 USD) Conversion from: -$62.21 USD Conversion to: b,47.00 EUR Exchange rate: 1 U.S. Dollar = 0.755505 Euros Item Amount: b,47.00 EUR Shipping: b,0.00 EUR Handling: b,0.00 EUR Quantity: 1 Item Title:OpenBSD Command-Line Companion Editions: PDF + Paper Item Number: 0008 Date: Feb 13, 2009 Time: 16:33:55 CST Status: Completed
Re: Jacek Books
By posting regarding this situation, possibly it will help others from being swindled. I paid for the "Firewall Book", and as stated, did receive a few PDF's, but that's it, no paper copy. Going through PayPal is is waste of time, as their time limits have been exceeded many times over (my purchase was Feb 13, 2009) for filing a complaint, unless I'm mistaken. When someone is ripping others off left and right, who gives a hang about copyrights ? Were I not honest, I surely wouldn't; I'd get what I paid for any way I could. Alas, I guess I just lost out, as it's evident from the site that business is in full swing and payment is being accepted by 2 methods. I guess I should have also noted that Artymiak was a Non-verified US vendor on PayPal. Live and learn I guess, at times the very hard way. I really expected much more from Artymiak. On 2/15/2010 2:31 PM, Corey wrote: On 02/15/2010 01:33 PM, open...@e-solutions.re wrote: Im agree with you Aaron, but i bought his books on 14 september 2009, and an other book on 14 october 2009. If you want i can send you my Paypal receipts to prove it. I never received the books. It is a swindle ! nothing else ... And why sell books when nobody to occupies his website? Even if he is ill, it is not a reason (he has to stop selling ebooks) Thank's Report him to PayPal. Depending on the terms of his copyrights, it may not be legal for someone else to send you a copy of his works. And if he is not responding to your personal emails, it is unlikely that posting on this list is going to help any further.
