RE: NANOG Digest, Vol 89, Issue 24

Not to inject more confusion - but GPS and NTP are noted in the thread... but not PTP (IEEE1588)? alex hardie | +1 404 229 7635 | www.nominum.com -----Original Message----- From: NANOG [mailto:nanog-bounces@nanog.org] On Behalf Of nanog-request@nanog.org Sent: Tuesday, June 23, 2015 8:00 AM To: nanog@nanog.org Subject: NANOG Digest, Vol 89, Issue 24 Send NANOG mailing list submissions to nanog@nanog.org To subscribe or unsubscribe via the World Wide Web, visit http://mailman.nanog.org/mailman/listinfo/nanog or, via email, send a message with subject or body 'help' to nanog-request@nanog.org You can reach the person managing the list at nanog-owner@nanog.org When replying, please edit your Subject line so it is more specific than "Re: Contents of NANOG digest..." Today's Topics: 1. Re: REMINDER: LEAP SECOND (Tony Finch) 2. Re: REMINDER: LEAP SECOND (Stephane Bortzmeyer) 3. Re: REMINDER: LEAP SECOND (Bjoern A. Zeeb) 4. Re: REMINDER: LEAP SECOND (Stephane Bortzmeyer) 5. Re: REMINDER: LEAP SECOND (Tony Finch) 6. Re: REMINDER: LEAP SECOND (Alan Buxey) 7. Re: REMINDER: LEAP SECOND (Saku Ytti) 8. Re: REMINDER: LEAP SECOND (Randy Bush) 9. Re: REMINDER: LEAP SECOND (shawn wilson) 10. Re: REMINDER: LEAP SECOND (Tony Finch) 11. Re: Data Center Network Monitoring with TAPs (Rafael Possamai) 12. Re: REMINDER: LEAP SECOND (Harlan Stenn) 13. Facebook contact, images issues in IL/WI (David Sovereen) 14. Re: REMINDER: LEAP SECOND (Marshall Eubanks) 15. Residential VSAT experiences? (Nicholas Oas) 16. Core alignment fusion splicers (Peter Kranz) 17. Re: Core alignment fusion splicers (Mel Beckman) 18. AW: Core alignment fusion splicers (J?rgen Jaritsch) 19. Re: Residential VSAT experiences? (William Herrin) 20. Re: REMINDER: LEAP SECOND (Doug Barton) 21. Re: Residential VSAT experiences? (Mike Lyon) 22. Re: Residential VSAT experiences? (Fred Baker (fred)) 23. Re: Residential VSAT experiences? (Dovid Bender) 24. Re: Residential VSAT experiences? (Mike Lyon) 25. Re: Residential VSAT experiences? (Hugo Slabbert) 26. Re: REMINDER: LEAP SECOND (Harlan Stenn) 27. Re: Residential VSAT experiences? (Mike Hale) 28. Re: Residential VSAT experiences? (Michael Conlen) 29. Re: Residential VSAT experiences? (Scott Weeks) 30. Fwd: Residential VSAT experiences? (Alfred Olton) 31. Re: Residential VSAT experiences? (Lyndon Nerenberg) 32. Re: Residential VSAT experiences? (TR Shaw) 33. Re: Residential VSAT experiences? (Dave Crocker) 34. Re: Residential VSAT experiences? (Mikael Abrahamsson) 35. Re: Residential VSAT experiences? (Dave Taht) 36. Re: REMINDER: LEAP SECOND (Mel Beckman) 37. Re: REMINDER: LEAP SECOND (Harlan Stenn) 38. Re: Residential VSAT experiences? (Tim Franklin) 39. Re: REMINDER: LEAP SECOND (Mel Beckman) 40. Re: REMINDER: LEAP SECOND (Nick Hilliard) ---------------------------------------------------------------------- Message: 1 Date: Mon, 22 Jun 2015 13:15:41 +0100 From: Tony Finch <dot@dotat.at> To: Harlan Stenn <stenn@ntp.org> Cc: Saku Ytti <saku@ytti.fi>, nanog@nanog.org Subject: Re: REMINDER: LEAP SECOND Message-ID: <alpine.LSU.2.00.1506221312330.3102@hermes-1.csi.cam.ac.uk> Content-Type: TEXT/PLAIN; charset=US-ASCII Harlan Stenn <stenn@ntp.org> wrote:
It's a problem with POSIX, not UTC.
UTC is monotonic.
The problems are that UTC is unpredictable, and it breaks the standard labelling of points in time that was used for hundreds (arguably thousands) of years before 1972. Tony. -- f.anthony.n.finch <dot@dotat.at> http://dotat.at/ Irish Sea: Northwesterly 4 or 5, occasionally 6 at first, becoming variable 4. Slight or moderate. Mainly fair. Good. ------------------------------ Message: 2 Date: Mon, 22 Jun 2015 14:27:18 +0200 From: Stephane Bortzmeyer <bortzmeyer@nic.fr> To: Tony Finch <dot@dotat.at> Cc: Harlan Stenn <stenn@ntp.org>, nanog@nanog.org Subject: Re: REMINDER: LEAP SECOND Message-ID: <20150622122718.GA10690@nic.fr> Content-Type: text/plain; charset=us-ascii On Mon, Jun 22, 2015 at 01:15:41PM +0100, Tony Finch <dot@dotat.at> wrote a message of 15 lines which said:
The problems are that UTC is unpredictable,
That's because the earth rotation is unpredictable. Any time based on this buggy planet's movements will be unpredictable. Let's patch it now! ------------------------------ Message: 3 Date: Mon, 22 Jun 2015 12:38:28 +0000 From: "Bjoern A. Zeeb" <bzeeb-lists@lists.zabbadoz.net> To: Stephane Bortzmeyer <bortzmeyer@nic.fr> Cc: Tony Finch <dot@dotat.at>, nanog@nanog.org Subject: Re: REMINDER: LEAP SECOND Message-ID: <8C40413B-B22C-4BCE-85D2-B4F93A233628@lists.zabbadoz.net> Content-Type: text/plain; charset=us-ascii
On 22 Jun 2015, at 12:27 , Stephane Bortzmeyer <bortzmeyer@nic.fr> wrote:
On Mon, Jun 22, 2015 at 01:15:41PM +0100, Tony Finch <dot@dotat.at> wrote a message of 15 lines which said:
The problems are that UTC is unpredictable,
That's because the earth rotation is unpredictable. Any time based on this buggy planet's movements will be unpredictable. Let's patch it now!
So we need a new center of the universe and switch to stardate and thus solve the 32bit UNIX time problem for real this time? ------------------------------ Message: 4 Date: Mon, 22 Jun 2015 14:44:15 +0200 From: Stephane Bortzmeyer <bortzmeyer@nic.fr> To: "Bjoern A. Zeeb" <bzeeb-lists@lists.zabbadoz.net> Cc: Stephane Bortzmeyer <bortzmeyer@nic.fr>, Tony Finch <dot@dotat.at>, nanog@nanog.org Subject: Re: REMINDER: LEAP SECOND Message-ID: <20150622124415.GA12276@nic.fr> Content-Type: text/plain; charset=us-ascii On Mon, Jun 22, 2015 at 12:38:28PM +0000, Bjoern A. Zeeb <bzeeb-lists@lists.zabbadoz.net> wrote a message of 17 lines which said:
So we need a new center of the universe and switch to stardate and thus solve the 32bit UNIX time problem for real this time?
Or simply use TAI which is the obvious time reference for Internet devices. Using UTC in routers is madness. Routers and Internet servers should use TAI internally and use UTC only when communicating with humans (the inferior life form which crawls on the Earth surface and cares about things like whether the sun is high at noon, for outside picnics). ------------------------------ Message: 5 Date: Mon, 22 Jun 2015 13:55:20 +0100 From: Tony Finch <dot@dotat.at> To: Stephane Bortzmeyer <bortzmeyer@nic.fr> Cc: nanog@nanog.org Subject: Re: REMINDER: LEAP SECOND Message-ID: <alpine.LSU.2.00.1506221353350.32296@hermes-1.csi.cam.ac.uk> Content-Type: TEXT/PLAIN; charset=US-ASCII Stephane Bortzmeyer <bortzmeyer@nic.fr> wrote:
That's because the earth rotation is unpredictable. Any time based on this buggy planet's movements will be unpredictable. Let's patch it now!
http://mm.icann.org/pipermail/tz/2015-May/022280.html http://mm.icann.org/pipermail/tz/2015-May/022281.html http://mm.icann.org/pipermail/tz/2015-May/022282.html Tony. -- f.anthony.n.finch <dot@dotat.at> http://dotat.at/ Northwest Faeroes, Southeast Iceland: Northeasterly 3 or 4. Moderate, becoming mainly slight. Mainly fair. Good, occasionally poor in Southeast Iceland. ------------------------------ Message: 6 Date: Mon, 22 Jun 2015 12:56:44 +0000 From: Alan Buxey <A.L.M.Buxey@lboro.ac.uk> To: "Bjoern A. Zeeb" <bzeeb-lists@lists.zabbadoz.net>, Stephane Bortzmeyer <bortzmeyer@nic.fr> Cc: "nanog@nanog.org" <nanog@nanog.org> Subject: Re: REMINDER: LEAP SECOND Message-ID: <AM3PR04MB35631C949345BC1CBCFC0C1A7A10@AM3PR04MB356.eurprd04.prod.outlook.com> Content-Type: text/plain; charset="iso-8859-1" I do feel sorry for you unix/linux users having a problem in year 2038.... fortunately I get another ~ 8 years... my Amiga gets its first big problem in 2046 ;-) http://web.archive.org/web/19981203142814/http://www.amiga.com/092098-y2k.ht... alan PS if i get to see the 2078 issue I'll be old enough to fuss about other things than a 2 digit date display..and I'm sure if I'm around until 7 February, 2114, 06:28:16 I'll have more to worry about than an old Amiga finally reaching the end of its useful life...unless its actually driving my life support system! ;-) ------------------------------ Message: 7 Date: Mon, 22 Jun 2015 16:23:11 +0300 From: Saku Ytti <saku@ytti.fi> To: nanog@nanog.org Subject: Re: REMINDER: LEAP SECOND Message-ID: <20150622132311.GA14699@pob.ytti.fi> Content-Type: text/plain; charset=us-ascii On (2015-06-22 14:44 +0200), Stephane Bortzmeyer wrote:
Or simply use TAI which is the obvious time reference for Internet devices. Using UTC in routers is madness. Routers and Internet servers should use TAI internally and use UTC only when communicating with humans (the inferior life form which crawls on the Earth surface and cares about things like whether the sun is high at noon, for outside picnics).
I couldn't agree more. But out of curiosity does anyone have scoop why TAI exists? I believe GPSTIME predates it, which appears analogous to TAI. -- ++ytti ------------------------------ Message: 8 Date: Mon, 22 Jun 2015 23:17:52 +0900 From: Randy Bush <randy@psg.com> To: Stephane Bortzmeyer <bortzmeyer@nic.fr> Cc: North American Network Operators' Group <nanog@nanog.org> Subject: Re: REMINDER: LEAP SECOND Message-ID: <m2616fddyn.wl%randy@psg.com> Content-Type: text/plain; charset=US-ASCII we can just turn the internet off for an hour until the dust settles. ------------------------------ Message: 9 Date: Mon, 22 Jun 2015 14:17:53 +0000 From: shawn wilson <ag4ve.us@gmail.com> To: Stephane Bortzmeyer <bortzmeyer@nic.fr>, Tony Finch <dot@dotat.at> Cc: nanog@nanog.org Subject: Re: REMINDER: LEAP SECOND Message-ID: <CAH_OBifuB5g52skBDm-Huj69-fxTkPYORSMW_qe-os6Gis8+Rw@mail.gmail.com> Content-Type: text/plain; charset=UTF-8 On Mon, Jun 22, 2015, 08:29 Stephane Bortzmeyer <bortzmeyer@nic.fr> wrote:
On Mon, Jun 22, 2015 at 01:15:41PM +0100, Tony Finch <dot@dotat.at> wrote a message of 15 lines which said:
The problems are that UTC is unpredictable,
That's because the earth rotation is unpredictable. Any time based on this buggy planet's movements will be unpredictable. Let's patch it now!
So, what we should do is make clocks move. 99999 slower half of the year (and then speed back up) so that we're really in line with earth's rotational time. I mean we've got the computers to do it (I think most RTC only go down to thousandths so it'll still need a little skewing but I'm sure we'll manage).
Ps - if anyone actually does this, I'm going postal. ------------------------------ Message: 10 Date: Mon, 22 Jun 2015 15:27:42 +0100 From: Tony Finch <dot@dotat.at> To: shawn wilson <ag4ve.us@gmail.com> Cc: Stephane Bortzmeyer <bortzmeyer@nic.fr>, nanog@nanog.org Subject: Re: REMINDER: LEAP SECOND Message-ID: <alpine.LSU.2.00.1506221524480.3102@hermes-1.csi.cam.ac.uk> Content-Type: TEXT/PLAIN; charset=US-ASCII shawn wilson <ag4ve.us@gmail.com> wrote:
So, what we should do is make clocks move. 99999 slower half of the year (and then speed back up) so that we're really in line with earth's rotational time.
That's how UTC worked in the 1960s. ftp://maia.usno.navy.mil/ser7/tai-utc.dat It causes problems for systems that have a tight coupling between time and frequency - broadcast, cellular, etc. Tony. -- f.anthony.n.finch <dot@dotat.at> http://dotat.at/ Fair Isle, Southeast Faeroes: Northeasterly 5 or 6 backing northerly 4 or 5. Moderate, occasionally rough at first. Mainly fair. Good. ------------------------------ Message: 11 Date: Mon, 22 Jun 2015 11:44:41 -0500 From: Rafael Possamai <rafael@gav.ufsc.br> To: Mitch Howards <hbf9121@hotmail.com> Cc: "nanog@nanog.org" <nanog@nanog.org> Subject: Re: Data Center Network Monitoring with TAPs Message-ID: <CAJB2g-Hy264X4LCZ2ddH636Kh9w6aU=vAhiO7i=FY3CVfCTu7A@mail.gmail.com> Content-Type: text/plain; charset=UTF-8 Here's a recent forum thread that discussed the same exact topic. You might find some insight: http://www.reddit.com/r/networking/comments/3aip3p/data_center_network_monit... On Sat, Jun 20, 2015 at 11:06 AM, Mitch Howards <hbf9121@hotmail.com> wrote:
Hello All,
Was wondering what folks are using to monitor traffic on their networks. Looking into Ixia and APCON devices for dedup and other filtering features as well as passive fiber TAPs to capture the traffic.
How are folks handling TAP'ing large data center networks? TAPs at the "distribution layer" would be the best fit for my network but that would require a ton of passive fiber TAPs for the incoming fibers to the distribution switches. The end goal is to not only capture the north-south traffic on the network but also east-west traffic. It seems more efficient to just use SPANs but there are many limitations using SPANs.
Thanks in advance for any suggestions.
Mitch
------------------------------ Message: 12 Date: Mon, 22 Jun 2015 17:58:54 +0000 From: Harlan Stenn <stenn@ntp.org> To: Tony Finch <dot@dotat.at> Cc: Harlan Stenn <stenn@ntp.org>, Saku Ytti <saku@ytti.fi>, nanog@nanog.org Subject: Re: REMINDER: LEAP SECOND Message-ID: <E1Z75zi-000LZc-P0@stenn.ntp.org> Content-Type: text/plain; charset=US-ASCII Tony Finch writes:
Harlan Stenn <stenn@ntp.org> wrote:
It's a problem with POSIX, not UTC.
UTC is monotonic.
The problems are that UTC is unpredictable, and it breaks the standard labelling of points in time that was used for hundreds (arguably thousands) of years before 1972.
You mean back when seconds were rubbery, and before the earth's rotational speed could be easily and accurately measured, or at least when the wobbles at that level of accuracy became so noticeable that they could no longer be ignored? H ------------------------------ Message: 13 Date: Mon, 22 Jun 2015 14:54:09 -0400 From: David Sovereen <david.sovereen@mercury.net> To: nanog@nanog.org Subject: Facebook contact, images issues in IL/WI Message-ID: <7FDC076C-51E9-4006-90B6-5991BC33D8DC@mercury.net> Content-Type: text/plain; charset=utf-8 Hello, If someone from Facebook is reading, please contact me off-list. Since last Thursday, our customers have been having image loading problems at Facebook.com <http://facebook.com/> We know it?s not just us?many users are reporting similar problems at https://downdetector.com/status/facebook/map/ <https://downdetector.com/status/facebook/map/> Would like to help get this resolved. Thanks, Dave ====================================================================== MERCURY NETWORK CORPORATION David Sovereen 920-686-4800 x 151 1011 Washington St Ste 3, Manitowoc, WI 54220-5248 http://www.mercury.net <http://www.mercury.net/> ------------------------------ Message: 14 Date: Mon, 22 Jun 2015 15:36:32 -0400 From: Marshall Eubanks <marshall.eubanks@gmail.com> To: Stephane Bortzmeyer <bortzmeyer@nic.fr> Cc: "Bjoern A. Zeeb" <bzeeb-lists@lists.zabbadoz.net>, "nanog@nanog.org" <nanog@nanog.org> Subject: Re: REMINDER: LEAP SECOND Message-ID: <CAJNg7VLRLLty=A75ehXvMK4TUViR9hiQyHtpvF29fopZX2jA6g@mail.gmail.com> Content-Type: text/plain; charset=UTF-8 On Mon, Jun 22, 2015 at 8:44 AM, Stephane Bortzmeyer <bortzmeyer@nic.fr> wrote:
On Mon, Jun 22, 2015 at 12:38:28PM +0000, Bjoern A. Zeeb <bzeeb-lists@lists.zabbadoz.net> wrote a message of 17 lines which said:
So we need a new center of the universe and switch to stardate and thus solve the 32bit UNIX time problem for real this time?
Or simply use TAI which is the obvious time reference for Internet devices. Using UTC in routers is madness. Routers and Internet servers should use TAI internally and use UTC only when communicating with humans (the inferior life form which crawls on the Earth surface and cares about things like whether the sun is high at noon, for outside picnics).
If the Earth's core ever decides to have some real fun and causes there to be a negative leap second (there is historical precedent for this, albeit before the existence of UTC and atomic time) there would be a minute with only 59 seconds, and I would expect things to break in new and creative ways. We live in a relatively narrow slice of time (a few decades) where this is a possibility, but it is a possibility. (Note that the number of leap seconds per year has _slowed_ recently, corresponding to a speed up in the long term averaged rotation of the Earth. If that speed up of the Earth's rotation were to happen again, negative leap seconds would be inevitable.) The drift between the Earth's time and atomic time will just get worse over longer time frames (see http://www.ucolick.org/~sla/leapsecs/year2100.html ). Even if UTC - TAI is just fixed (i.e., no more leap seconds), that is just pushing the problem down the road, and our grandkids will have to deal with leap minutes, or our remoter descendants with leap hours.
It's a problem with POSIX, not UTC.
Yes. I remember this being raised by people at the USNO back in the early 1990's, but there was no interest in changing POSIX. Too much installed base was the reason stated IIRC. My opinion is (and has been since the early 90's) that the computer / Internet world should just adopt IAT as the time system in use. That is the best time we have, and it will never have steps. Yes, that means that you would need something like a time zone file to set your system clock by hand from local (UTC) time, but, then, we already have to have time zone files. Regards Marshall Eubanks ------------------------------ Message: 15 Date: Mon, 22 Jun 2015 16:39:27 -0400 From: Nicholas Oas <nicholas.oas@gmail.com> To: "nanog@nanog.org" <nanog@nanog.org> Subject: Residential VSAT experiences? Message-ID: <CAHnk=Cj4uRgyyMOW+BbgLpqPAbKCPPiLLT+sMXnfb2Jf+j8vSg@mail.gmail.com> Content-Type: text/plain; charset=UTF-8 Would anyone mind sharing with me their first-hand experiences with residential satellite internet? Right now I am evaluating HughesNet Gen4 and ViaSat Exede and I'm thinking specifically as a sysadmin who needs to use the uplink for work, not surf. What are your experiences with the following applications? -SSH, (specifically interactive CLI shell access) -RDP -SIP over SSL -IPSec Tunneling (should be a non-starter due to latency) -GRE Tunneling Thank you, -Nicholas ------------------------------ Message: 16 Date: Mon, 22 Jun 2015 13:58:21 -0700 From: "Peter Kranz" <pkranz@unwiredltd.com> To: <nanog@nanog.org> Subject: Core alignment fusion splicers Message-ID: <20ac01d0ad2e$2c76fa00$8564ee00$@unwiredltd.com> Content-Type: text/plain; charset="us-ascii" Curious if any of you have favorites when it comes to fusion splicers.. There is a huge range in price for units that appear to be very similar in both specifications and appearance. Currently considering standardizing on the INNO View 5 http://www.innoinstrument.com/new/splicer/view5.php , but we need enough of these units I'd love stories from the field before dropping the order. Peter Kranz www.UnwiredLtd.com <http://www.unwiredltd.com/> Desk: 510-868-1614 x100 Mobile: 510-207-0000 pkranz@unwiredltd.com <mailto:pkranz@unwiredltd.com> ------------------------------ Message: 17 Date: Mon, 22 Jun 2015 21:06:09 +0000 From: Mel Beckman <mel@beckman.org> To: Peter Kranz <pkranz@unwiredltd.com> Cc: "<nanog@nanog.org>" <nanog@nanog.org> Subject: Re: Core alignment fusion splicers Message-ID: <E460D466-7B62-401E-A6B1-B6756C0FF56C@beckman.org> Content-Type: text/plain; charset="utf-8" Don?t buy to start. Instead, rent a few different brands for splicing projects until you know what features you need and want. And don?t scrimp on the cleaver. Get a quality automatic cleaver (these usually come in the rental bundle). -mel
On Jun 22, 2015, at 1:58 PM, Peter Kranz <pkranz@unwiredltd.com> wrote:
Curious if any of you have favorites when it comes to fusion splicers.. There is a huge range in price for units that appear to be very similar in both specifications and appearance. Currently considering standardizing on the INNO View 5 http://www.innoinstrument.com/new/splicer/view5.php , but we need enough of these units I'd love stories from the field before dropping the order.
Peter Kranz www.UnwiredLtd.com <http://www.unwiredltd.com/> Desk: 510-868-1614 x100 Mobile: 510-207-0000 pkranz@unwiredltd.com <mailto:pkranz@unwiredltd.com>
------------------------------ Message: 18 Date: Mon, 22 Jun 2015 21:07:41 +0000 From: J?rgen Jaritsch <jj@anexia.at> To: Peter Kranz <pkranz@unwiredltd.com>, "nanog@nanog.org" <nanog@nanog.org> Subject: AW: Core alignment fusion splicers Message-ID: <515026f2064b40768f82af92334ba8f4@anx-i-dag02.anx.local> Content-Type: text/plain; charset="iso-8859-1" Hi, We do not have the new View-series but we're working with the IFS-10: http://www.innoinstrument.com/new/splicer/ifs10.php Easy to use. Works quite good under rough conditions. Not THAT expensive. Battery lifetime is ok. Best regards J?rgen Jaritsch Head of Network & Infrastructure ANEXIA Internetdienstleistungs GmbH Telefon: +43-5-0556-300 Telefax: +43-5-0556-500 E-Mail: jj@anexia.at Web: http://www.anexia.at Anschrift Hauptsitz Klagenfurt: Feldkirchnerstra?e 140, 9020 Klagenfurt Gesch?ftsf?hrer: Alexander Windbichler Firmenbuch: FN 289918a | Gerichtsstand: Klagenfurt | UID-Nummer: AT U63216601 -----Urspr?ngliche Nachricht----- Von: NANOG [mailto:nanog-bounces@nanog.org] Im Auftrag von Peter Kranz Gesendet: Montag, 22. Juni 2015 22:58 An: nanog@nanog.org Betreff: Core alignment fusion splicers Curious if any of you have favorites when it comes to fusion splicers.. There is a huge range in price for units that appear to be very similar in both specifications and appearance. Currently considering standardizing on the INNO View 5 http://www.innoinstrument.com/new/splicer/view5.php , but we need enough of these units I'd love stories from the field before dropping the order. Peter Kranz www.UnwiredLtd.com <http://www.unwiredltd.com/> Desk: 510-868-1614 x100 Mobile: 510-207-0000 pkranz@unwiredltd.com <mailto:pkranz@unwiredltd.com> ------------------------------ Message: 19 Date: Mon, 22 Jun 2015 18:11:38 -0400 From: William Herrin <bill@herrin.us> To: Nicholas Oas <nicholas.oas@gmail.com> Cc: "nanog@nanog.org" <nanog@nanog.org> Subject: Re: Residential VSAT experiences? Message-ID: <CAP-guGWod0ayQMq31ajL1Bq3cR3gS9uhh8i6Q9XwwEmnycOa9Q@mail.gmail.com> Content-Type: text/plain; charset=UTF-8 On Mon, Jun 22, 2015 at 4:39 PM, Nicholas Oas <nicholas.oas@gmail.com> wrote:
Would anyone mind sharing with me their first-hand experiences with residential satellite internet?
Hi Nicholas, Two-way satellite systems based on SV's in geostationary orbit (like the two you're considering) have high latency. 22,000 miles out, another 22,000 miles back and do it again for the return packet. You'll start around 500ms latency and go up from there. Any kind of interactive session (like SSH and RDP) will be excruciating. I'm not aware of any low earth orbit systems providing residential Internet. Iridium tries to but the bandwidth is pathetic (2400bps or so). LEO vehicles are only 500-1000 miles up. Latency is high compared to wireline systems but within usable bounds for interactive sessions. Regards, Bill Herrin -- William Herrin ................ herrin@dirtside.com bill@herrin.us Owner, Dirtside Systems ......... Web: <http://www.dirtside.com/> ------------------------------ Message: 20 Date: Mon, 22 Jun 2015 15:18:14 -0700 From: Doug Barton <dougb@dougbarton.us> To: nanog@nanog.org Subject: Re: REMINDER: LEAP SECOND Message-ID: <558889A6.10704@dougbarton.us> Content-Type: text/plain; charset="utf-8"; Format="flowed" On 6/19/15 2:58 PM, Harlan Stenn wrote:
Bad idea.
When restarting ntpd your clocks will likely be off by a second, which will cause a backward step, which will force the problem you claim to be avoiding.
There are plenty of ways to solve this problem, and you just get to choose what you want to risk/pay.
You misunderstand the problem. :) The problem is not "clock skips backward one second," because most of the time that's not what happens. The problem is that most software does not handle it well when the clock ticks ... :59 :60 :00 instead of ticking directly from :59 to :00. THAT problem is avoided by temporarily turning off NTP and then turning it back on again when "the coast is clear." Most software can handle the "clock skips forward or backwards one second" problem fairly robustly, and as Baldur pointed out by doing the reset in a controlled manner you greatly reduce your overall risk. Doug -- I am conducting an experiment in the efficacy of PGP/MIME signatures. This message should be signed. If it is not, or the signature does not validate, please let me know how you received this message (direct, or to a list) and the mail software you use. Thanks!
participants (2)
-
Alex Hardie
-
Harlan Stenn