Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]
Groups > comp.os.linux.networking > #2783 > unrolled thread
| Started by | Liam O'Connor <liamoconnor@example.com> |
|---|---|
| First post | 2014-03-08 00:53 -0800 |
| Last post | 2014-03-08 17:42 -0800 |
| Articles | 20 on this page of 68 — 12 participants |
Back to article view | Back to comp.os.linux.networking
How to set up a spare Linksys WRT54Gv2 as a wired access point network extender Liam O'Connor <liamoconnor@example.com> - 2014-03-08 00:53 -0800
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender Dan Purgert <dan@djph.net> - 2014-03-08 07:46 -0500
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender Liam O'Connor <liamoconnor@example.com> - 2014-03-08 10:56 -0800
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender Liam O'Connor <liamoconnor@example.com> - 2014-03-08 10:58 -0800
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender Liam O'Connor <liamoconnor@example.com> - 2014-03-08 11:51 -0800
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender Dan Purgert <dan@djph.net> - 2014-03-08 15:25 -0500
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender Scott Hemphill <hemphill@hemphills.net> - 2014-03-08 21:07 -0500
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender Scott Hemphill <hemphill@hemphills.net> - 2014-03-08 21:18 -0500
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender DecadentLinuxUserNumeroUno <DLU1@DecadentLinuxUser.org> - 2014-03-08 20:49 -0800
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender Mark Lloyd <mark@this.is.not.email.invalid> - 2014-03-09 10:50 -0500
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender Bit Twister <BitTwister@mouse-potato.com> - 2014-03-09 02:49 +0000
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender DecadentLinuxUserNumeroUno <DLU1@DecadentLinuxUser.org> - 2014-03-08 20:51 -0800
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender floyd@apaflo.com (Floyd L. Davidson) - 2014-03-08 23:56 -0900
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender DecadentLinuxUserNumeroUno <DLU1@DecadentLinuxUser.org> - 2014-03-09 09:39 -0700
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender floyd@apaflo.com (Floyd L. Davidson) - 2014-03-09 11:07 -0800
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender floyd@apaflo.com (Floyd L. Davidson) - 2014-03-08 23:20 -0900
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender Liam O'Connor <liamoconnor@example.com> - 2014-03-09 07:40 -0700
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender Dan Purgert <dan@djph.net> - 2014-03-09 21:19 -0400
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender DecadentLinuxUserNumeroUno <DLU1@DecadentLinuxUser.org> - 2014-03-09 09:21 -0700
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender floyd@apaflo.com (Floyd L. Davidson) - 2014-03-09 10:57 -0800
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender DecadentLinuxUserNumeroUno <DLU1@DecadentLinuxUser.org> - 2014-03-09 16:07 -0700
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender floyd@apaflo.com (Floyd L. Davidson) - 2014-03-09 17:05 -0800
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender Liam O'Connor <liamoconnor@example.com> - 2014-03-10 10:40 -0700
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender floyd@apaflo.com (Floyd L. Davidson) - 2014-03-10 12:06 -0800
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender DecadentLinuxUserNumeroUno <DLU1@DecadentLinuxUser.org> - 2014-03-10 20:07 -0700
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender floyd@apaflo.com (Floyd L. Davidson) - 2014-03-11 02:36 -0800
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender DecadentLinuxUserNumeroUno <DLU1@DecadentLinuxUser.org> - 2014-03-11 19:30 -0700
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender floyd@apaflo.com (Floyd L. Davidson) - 2014-03-11 23:13 -0800
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender DecadentLinuxUserNumeroUno <DLU1@DecadentLinuxUser.org> - 2014-03-12 21:30 -0700
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender floyd@apaflo.com (Floyd L. Davidson) - 2014-03-13 04:44 -0800
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender DecadentLinuxUserNumeroUno <DLU1@DecadentLinuxUser.org> - 2014-03-13 20:20 -0700
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender floyd@apaflo.com (Floyd L. Davidson) - 2014-03-13 20:30 -0800
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender DecadentLinuxUserNumeroUno <DLU1@DecadentLinuxUser.org> - 2014-03-13 22:59 -0700
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender mechanic <mechanic@example.net> - 2014-03-14 11:31 +0000
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender DecadentLinuxUserNumeroUno <DLU1@DecadentLinuxUser.org> - 2014-03-14 21:50 -0700
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender floyd@apaflo.com (Floyd L. Davidson) - 2014-03-14 04:31 -0800
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender mechanic <mechanic@example.net> - 2014-03-14 13:45 +0000
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender floyd@apaflo.com (Floyd L. Davidson) - 2014-03-14 07:26 -0800
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender John Hasler <jhasler@newsguy.com> - 2014-03-14 11:07 -0500
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender floyd@apaflo.com (Floyd L. Davidson) - 2014-03-14 10:23 -0800
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender DecadentLinuxUserNumeroUno <DLU1@DecadentLinuxUser.org> - 2014-03-14 22:02 -0700
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender floyd@apaflo.com (Floyd L. Davidson) - 2014-03-14 21:53 -0800
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender DecadentLinuxUserNumeroUno <DLU1@DecadentLinuxUser.org> - 2014-03-15 09:49 -0700
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender mechanic <mechanic@example.net> - 2014-03-15 10:45 +0000
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender DecadentLinuxUserNumeroUno <DLU1@DecadentLinuxUser.org> - 2014-03-15 09:57 -0700
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender floyd@apaflo.com (Floyd L. Davidson) - 2014-03-15 12:28 -0800
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender DecadentLinuxUserNumeroUno <DLU1@DecadentLinuxUser.org> - 2014-03-15 14:02 -0700
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender floyd@apaflo.com (Floyd L. Davidson) - 2014-03-15 14:22 -0800
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender DecadentLinuxUserNumeroUno <DLU1@DecadentLinuxUser.org> - 2014-03-15 21:55 -0700
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender floyd@apaflo.com (Floyd L. Davidson) - 2014-03-15 21:25 -0800
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender DecadentLinuxUserNumeroUno <DLU1@DecadentLinuxUser.org> - 2014-03-14 21:54 -0700
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender DecadentLinuxUserNumeroUno <DLU1@DecadentLinuxUser.org> - 2014-03-14 21:58 -0700
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender DecadentLinuxUserNumeroUno <DLU1@DecadentLinuxUser.org> - 2014-03-11 19:33 -0700
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender floyd@apaflo.com (Floyd L. Davidson) - 2014-03-11 23:36 -0800
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender ceed <ceed@is.indeed.invalid> - 2014-03-12 17:05 +0000
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender DecadentLinuxUserNumeroUno <DLU1@DecadentLinuxUser.org> - 2014-03-12 21:48 -0700
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender floyd@apaflo.com (Floyd L. Davidson) - 2014-03-13 04:46 -0800
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender Eef Hartman <E.J.M.Hartman@tudelft.nl> - 2014-03-12 19:27 +0000
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender floyd@apaflo.com (Floyd L. Davidson) - 2014-03-12 13:32 -0800
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender DecadentLinuxUserNumeroUno <DLU1@DecadentLinuxUser.org> - 2014-03-13 19:18 -0700
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender Liam O'Connor <liamoconnor@example.com> - 2014-03-08 10:59 -0800
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender Liam O'Connor <liamoconnor@example.com> - 2014-03-08 11:01 -0800
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender Dan Purgert <dan@djph.net> - 2014-03-08 15:36 -0500
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender Liam O'Connor <liamoconnor@example.com> - 2014-03-08 19:06 -0800
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender DecadentLinuxUserNumeroUno <DLU1@DecadentLinuxUser.org> - 2014-03-08 20:54 -0800
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender Dan Purgert <dan@djph.net> - 2014-03-09 08:03 -0400
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender Liam O'Connor <liamoconnor@example.com> - 2014-03-09 07:56 -0700
Re: How to set up a spare Linksys WRT54Gv2 as a wired access point network extender Big Bad Bob <BigBadBob-at-mrp3-dot-com@testing.local> - 2014-03-08 17:42 -0800
Page 2 of 4 — ← Prev page 1 [2] 3 4 Next page →
| From | DecadentLinuxUserNumeroUno <DLU1@DecadentLinuxUser.org> |
|---|---|
| Date | 2014-03-09 16:07 -0700 |
| Message-ID | <c1tph9lgell4g9g0a6ilhlon4fnouusmip@4ax.com> |
| In reply to | #2810 |
On Sun, 09 Mar 2014 10:57:21 -0800, floyd@apaflo.com (Floyd L. Davidson) Gave us: > >The twist rate differs on *any* cable with multiple twisted pairs. Cat 6 has VERY specific twist rates and they differ in the same wire very specifically. It is not just some lame manufacturing window the maker of the wire needs to comply with to make the claim of it being a certain wire. They are specifically (with cat5e and up) two different twist rates and belong at different locations on the GbE port and therefore also on the connector that gets you into that port. Sure, you may get a handshake with your sub orthodox jumper, but why differ from what the entire rest of the world does? And no, your jumper will not work correctly on a real network link that fully taxes the link as a part of its built in reliability testing. A bad link anywhere in our gateways gets found pretty much instantaneously. Subbing in a sub par jumper gets noted in the functional testing, so it must make a difference. Think Nyquist. BTW, Floyd.. I consider you as one of the most intelligent folks on Usenet and always have for a couple decades now. Back when a.e.e. was more popular.
[toc] | [prev] | [next] | [standalone]
| From | floyd@apaflo.com (Floyd L. Davidson) |
|---|---|
| Date | 2014-03-09 17:05 -0800 |
| Message-ID | <87a9cyoocb.fld@apaflo.com> |
| In reply to | #2812 |
DecadentLinuxUserNumeroUno <DLU1@DecadentLinuxUser.org> wrote:
>On Sun, 09 Mar 2014 10:57:21 -0800, floyd@apaflo.com (Floyd L. Davidson)
>Gave us:
>
>>
>>The twist rate differs on *any* cable with multiple twisted pairs.
>
> Cat 6 has VERY specific twist rates and they differ in the same wire
>very specifically. It is not just some lame manufacturing window the
>maker of the wire needs to comply with to make the claim of it being a
>certain wire. They are specifically (with cat5e and up) two different
>twist rates and belong at different locations on the GbE port and
>therefore also on the connector that gets you into that port.
>
> Sure, you may get a handshake with your sub orthodox jumper, but why
>differ from what the entire rest of the world does?
It makes exactly *no* difference which pair has which twist rate
or which pair carries which data.
Twist rates are also defined specifically in other cables, but
in fact for Cat 5 cable they are defined as:
Pair Turns per meter
Blue 64.8
Orange 56.2
Green 65.2
Brown 51.7
Note that per TIA/EIA-A and TIA/EIA-B the data will be on the
Orange and Green pairs. Green has the highest twist and Orange is
the next to the lowest, clearly indicating that twist is not
significant to the data rate.
If maximum difference were important, the twist rates for Brown
and Blue would have been used for Orange and Green. If the hightest
twist rate was significant, the twist rate for Blue would have been
assigned to Orange instead. But in fact *any* twist rate above 50 per
meter is enough.
> And no, your jumper will not work correctly on a real network link
>that fully taxes the link as a part of its built in reliability testing.
The hardware cannot detect which twist rate is used on a pair.
> A bad link anywhere in our gateways gets found pretty much
>instantaneously. Subbing in a sub par jumper gets noted in the
>functional testing, so it must make a difference. Think Nyquist.
How does Nyquist relate to cable pair twist?
The different twist rates are meant to avoid two pairs laying
too close to each other over any significant distance.
Using different twist rates has been standard practice with
multipair twisted pair cable essentially since Alexander Bell
discovered the advantages of twisted pair cables. (Don't think
Nyquist, think about open wire line!)
> BTW, Floyd.. I consider you as one of the most intelligent folks on
>Usenet and always have for a couple decades now. Back when a.e.e. was
>more popular.
Intelligence may be overrated, and I certainly don't claim to
have much. What I do have is a few decades of experience with
testing comm cabling.
--
Floyd L. Davidson http://www.apaflo.com/
Ukpeagvik (Barrow, Alaska) floyd@apaflo.com
[toc] | [prev] | [next] | [standalone]
| From | Liam O'Connor <liamoconnor@example.com> |
|---|---|
| Date | 2014-03-10 10:40 -0700 |
| Message-ID | <9b626$531df921$43da7656$19279@nntpswitch.blueworldhosting.com> |
| In reply to | #2808 |
On Sun, 09 Mar 2014 09:21:21 -0700, DecadentLinuxUserNumeroUno wrote: > The twist per inch rates of each pair DIFFER in the new cabling. This is quite interesting!
[toc] | [prev] | [next] | [standalone]
| From | floyd@apaflo.com (Floyd L. Davidson) |
|---|---|
| Date | 2014-03-10 12:06 -0800 |
| Message-ID | <8761nlom24.fld@apaflo.com> |
| In reply to | #2815 |
Liam O'Connor <liamoconnor@example.com> wrote: >On Sun, 09 Mar 2014 09:21:21 -0700, DecadentLinuxUserNumeroUno wrote: > >> The twist per inch rates of each pair DIFFER in the new cabling. > >This is quite interesting! But of course that is not unique to "the new cabling". Multipair twisted pair cable has all been made that way for literally decades, long before the advent of Ethernet. -- Floyd L. Davidson http://www.apaflo.com/ Ukpeagvik (Barrow, Alaska) floyd@apaflo.com
[toc] | [prev] | [next] | [standalone]
| From | DecadentLinuxUserNumeroUno <DLU1@DecadentLinuxUser.org> |
|---|---|
| Date | 2014-03-10 20:07 -0700 |
| Message-ID | <ndvsh91sr7chqtk7nfaoqct5ud13acrtei@4ax.com> |
| In reply to | #2815 |
On Mon, 10 Mar 2014 10:40:47 -0700, Liam O'Connor <liamoconnor@example.com> Gave us: >On Sun, 09 Mar 2014 09:21:21 -0700, DecadentLinuxUserNumeroUno wrote: > >> The twist per inch rates of each pair DIFFER in the new cabling. > >This is quite interesting! Apparently not to some. I can guarantee you it IS of interest to the hardware you are hooking into. Some of it even cares one way or the other.
[toc] | [prev] | [next] | [standalone]
| From | floyd@apaflo.com (Floyd L. Davidson) |
|---|---|
| Date | 2014-03-11 02:36 -0800 |
| Message-ID | <87wqg1m37t.fld@apaflo.com> |
| In reply to | #2817 |
DecadentLinuxUserNumeroUno <DLU1@DecadentLinuxUser.org> wrote: >On Mon, 10 Mar 2014 10:40:47 -0700, Liam O'Connor ><liamoconnor@example.com> Gave us: > >>On Sun, 09 Mar 2014 09:21:21 -0700, DecadentLinuxUserNumeroUno wrote: >> >>> The twist per inch rates of each pair DIFFER in the new cabling. >> >>This is quite interesting! > > Apparently not to some. It is of interest to virtually everyone. It was discovered by Alexander Graham Bell himself. > I can guarantee you it IS of interest to the hardware you are hooking >into. Some of it even cares one way or the other. Show us a cite where *anyone* that is credible demonstrates that as a fact. I guarantee you the hardware cannot determine the difference in twist rate between 50 per meter and 70 per meter. Which is to say that it cannot determine which pair is which in a CAT 5 cable. -- Floyd L. Davidson http://www.apaflo.com/ Ukpeagvik (Barrow, Alaska) floyd@apaflo.com
[toc] | [prev] | [next] | [standalone]
| From | DecadentLinuxUserNumeroUno <DLU1@DecadentLinuxUser.org> |
|---|---|
| Date | 2014-03-11 19:30 -0700 |
| Message-ID | <1ihvh9p3mvq5bobp4584cqukk8h7q1qfms@4ax.com> |
| In reply to | #2818 |
On Tue, 11 Mar 2014 02:36:38 -0800, floyd@apaflo.com (Floyd L. Davidson) Gave us: >It is of interest to virtually everyone. Apparently not. > It was discovered by >Alexander Graham Bell himself. You mean the jackass who stole the phone from Meucci? Doubtful he came upi with anything himself. He and his employer were pure thieves. Yeah... I have every confidence that he knew what latency was... NOT!
[toc] | [prev] | [next] | [standalone]
| From | floyd@apaflo.com (Floyd L. Davidson) |
|---|---|
| Date | 2014-03-11 23:13 -0800 |
| Message-ID | <87siqnnb2u.fld@apaflo.com> |
| In reply to | #2819 |
DecadentLinuxUserNumeroUno <DLU1@DecadentLinuxUser.org> wrote: >On Tue, 11 Mar 2014 02:36:38 -0800, floyd@apaflo.com (Floyd L. Davidson) >Gave us: > >>It is of interest to virtually everyone. > > Apparently not. > >> It was discovered by >>Alexander Graham Bell himself. > > You mean the jackass who stole the phone from Meucci? > > Doubtful he came upi with anything himself. He and his employer were >pure thieves. > > Yeah... I have every confidence that he knew what latency was... NOT! What does latency have to do with this discussion? -- Floyd L. Davidson http://www.apaflo.com/ Ukpeagvik (Barrow, Alaska) floyd@apaflo.com
[toc] | [prev] | [next] | [standalone]
| From | DecadentLinuxUserNumeroUno <DLU1@DecadentLinuxUser.org> |
|---|---|
| Date | 2014-03-12 21:30 -0700 |
| Message-ID | <h0d2i9d8belrc220jvkrcbe5dtbsmlmoeg@4ax.com> |
| In reply to | #2821 |
On Tue, 11 Mar 2014 23:13:45 -0800, floyd@apaflo.com (Floyd L. Davidson) Gave us: >DecadentLinuxUserNumeroUno <DLU1@DecadentLinuxUser.org> wrote: >>On Tue, 11 Mar 2014 02:36:38 -0800, floyd@apaflo.com (Floyd L. Davidson) >>Gave us: >> >>>It is of interest to virtually everyone. >> >> Apparently not. >> >>> It was discovered by >>>Alexander Graham Bell himself. >> >> You mean the jackass who stole the phone from Meucci? >> >> Doubtful he came upi with anything himself. He and his employer were >>pure thieves. >> >> Yeah... I have every confidence that he knew what latency was... NOT! > >What does latency have to do with this discussion? The different characteristic of the two types of tp included in the cable. It allows the port hardware to perform the testing I mentioned.
[toc] | [prev] | [next] | [standalone]
| From | floyd@apaflo.com (Floyd L. Davidson) |
|---|---|
| Date | 2014-03-13 04:44 -0800 |
| Message-ID | <87bnxamfoe.fld@apaflo.com> |
| In reply to | #2826 |
DecadentLinuxUserNumeroUno <DLU1@DecadentLinuxUser.org> wrote: >On Tue, 11 Mar 2014 23:13:45 -0800, floyd@apaflo.com (Floyd L. Davidson) >Gave us: > >>DecadentLinuxUserNumeroUno <DLU1@DecadentLinuxUser.org> wrote: >>>On Tue, 11 Mar 2014 02:36:38 -0800, floyd@apaflo.com (Floyd L. Davidson) >>>Gave us: >>> >>>>It is of interest to virtually everyone. >>> >>> Apparently not. >>> >>>> It was discovered by >>>>Alexander Graham Bell himself. >>> >>> You mean the jackass who stole the phone from Meucci? >>> >>> Doubtful he came upi with anything himself. He and his employer were >>>pure thieves. >>> >>> Yeah... I have every confidence that he knew what latency was... NOT! >> >>What does latency have to do with this discussion? > > The different characteristic of the two types of tp included in the >cable. It allows the port hardware to perform the testing I mentioned. Which is to say that latency has exactly nothing to do with the cable used, with the twist rate, or the non-existant testing you claim. Latency is not a function of the cable. -- Floyd L. Davidson http://www.apaflo.com/ Ukpeagvik (Barrow, Alaska) floyd@apaflo.com
[toc] | [prev] | [next] | [standalone]
| From | DecadentLinuxUserNumeroUno <DLU1@DecadentLinuxUser.org> |
|---|---|
| Date | 2014-03-13 20:20 -0700 |
| Message-ID | <n5t4i95jv5cbj653qdi9gpo6244nv4hh0r@4ax.com> |
| In reply to | #2828 |
On Thu, 13 Mar 2014 04:44:17 -0800, floyd@apaflo.com (Floyd L. Davidson) Gave us: >DecadentLinuxUserNumeroUno <DLU1@DecadentLinuxUser.org> wrote: >>On Tue, 11 Mar 2014 23:13:45 -0800, floyd@apaflo.com (Floyd L. Davidson) >>Gave us: >> >>>DecadentLinuxUserNumeroUno <DLU1@DecadentLinuxUser.org> wrote: >>>>On Tue, 11 Mar 2014 02:36:38 -0800, floyd@apaflo.com (Floyd L. Davidson) >>>>Gave us: >>>> >>>>>It is of interest to virtually everyone. >>>> >>>> Apparently not. >>>> >>>>> It was discovered by >>>>>Alexander Graham Bell himself. >>>> >>>> You mean the jackass who stole the phone from Meucci? >>>> >>>> Doubtful he came upi with anything himself. He and his employer were >>>>pure thieves. >>>> >>>> Yeah... I have every confidence that he knew what latency was... NOT! >>> >>>What does latency have to do with this discussion? >> >> The different characteristic of the two types of tp included in the >>cable. It allows the port hardware to perform the testing I mentioned. > >Which is to say that latency has exactly nothing to do with the cable >used, with the twist rate, or the non-existant testing you claim. > >Latency is not a function of the cable. It is a function of the test. Mustn't put badly fabbed cables into the system. Nice pass on backing up Bell.
[toc] | [prev] | [next] | [standalone]
| From | floyd@apaflo.com (Floyd L. Davidson) |
|---|---|
| Date | 2014-03-13 20:30 -0800 |
| Message-ID | <8761nhl7v8.fld@apaflo.com> |
| In reply to | #2832 |
DecadentLinuxUserNumeroUno <DLU1@DecadentLinuxUser.org> wrote: >On Thu, 13 Mar 2014 04:44:17 -0800, floyd@apaflo.com (Floyd L. Davidson) >Gave us: > >>DecadentLinuxUserNumeroUno <DLU1@DecadentLinuxUser.org> wrote: >>>On Tue, 11 Mar 2014 23:13:45 -0800, floyd@apaflo.com (Floyd L. Davidson) >>>Gave us: >>> >>>>DecadentLinuxUserNumeroUno <DLU1@DecadentLinuxUser.org> wrote: >>>>>On Tue, 11 Mar 2014 02:36:38 -0800, floyd@apaflo.com (Floyd L. Davidson) >>>>>Gave us: >>>>> >>>>>>It is of interest to virtually everyone. >>>>> >>>>> Apparently not. >>>>> >>>>>> It was discovered by >>>>>>Alexander Graham Bell himself. >>>>> >>>>> You mean the jackass who stole the phone from Meucci? >>>>> >>>>> Doubtful he came upi with anything himself. He and his employer were >>>>>pure thieves. >>>>> >>>>> Yeah... I have every confidence that he knew what latency was... NOT! >>>> >>>>What does latency have to do with this discussion? >>> >>> The different characteristic of the two types of tp included in the >>>cable. It allows the port hardware to perform the testing I mentioned. >> >>Which is to say that latency has exactly nothing to do with the cable >>used, with the twist rate, or the non-existant testing you claim. >> >>Latency is not a function of the cable. > > It is a function of the test. Do you know what "latency" means. A test does not have latency any more than a cable does. > Mustn't put badly fabbed cables into the system. > > Nice pass on backing up Bell. Poor digression on your part, but it does demonstrate a certain level of integrity, or lack of such. -- Floyd L. Davidson http://www.apaflo.com/ Ukpeagvik (Barrow, Alaska) floyd@apaflo.com
[toc] | [prev] | [next] | [standalone]
| From | DecadentLinuxUserNumeroUno <DLU1@DecadentLinuxUser.org> |
|---|---|
| Date | 2014-03-13 22:59 -0700 |
| Message-ID | <gb35i9dfm1d0127bai3rd61en36tl67im0@4ax.com> |
| In reply to | #2833 |
On Thu, 13 Mar 2014 20:30:35 -0800, floyd@apaflo.com (Floyd L. Davidson) Gave us: >DecadentLinuxUserNumeroUno <DLU1@DecadentLinuxUser.org> wrote: >>On Thu, 13 Mar 2014 04:44:17 -0800, floyd@apaflo.com (Floyd L. Davidson) >>Gave us: >> >>>DecadentLinuxUserNumeroUno <DLU1@DecadentLinuxUser.org> wrote: >>>>On Tue, 11 Mar 2014 23:13:45 -0800, floyd@apaflo.com (Floyd L. Davidson) >>>>Gave us: >>>> >>>>>DecadentLinuxUserNumeroUno <DLU1@DecadentLinuxUser.org> wrote: >>>>>>On Tue, 11 Mar 2014 02:36:38 -0800, floyd@apaflo.com (Floyd L. Davidson) >>>>>>Gave us: >>>>>> >>>>>>>It is of interest to virtually everyone. >>>>>> >>>>>> Apparently not. >>>>>> >>>>>>> It was discovered by >>>>>>>Alexander Graham Bell himself. >>>>>> >>>>>> You mean the jackass who stole the phone from Meucci? >>>>>> >>>>>> Doubtful he came upi with anything himself. He and his employer were >>>>>>pure thieves. >>>>>> >>>>>> Yeah... I have every confidence that he knew what latency was... NOT! >>>>> >>>>>What does latency have to do with this discussion? >>>> >>>> The different characteristic of the two types of tp included in the >>>>cable. It allows the port hardware to perform the testing I mentioned. >>> >>>Which is to say that latency has exactly nothing to do with the cable >>>used, with the twist rate, or the non-existant testing you claim. >>> >>>Latency is not a function of the cable. >> >> It is a function of the test. > >Do you know what "latency" means. Is that a question? > A test does not have latency >any more than a cable does. The test(s) utilize timing differences to make the aforementioned determinations. > >> Mustn't put badly fabbed cables into the system. >> >> Nice pass on backing up Bell. > >Poor digression on your part, Where? You mentioned an asshole and described him like he was some fucking god. I mentioned that he was an asshole, and you didn't even retort. I guess I wouldn't want you in the same foxhole as I. I wont digress to relinquishment of trust. Digression, my ass. > but it does demonstrate a certain >level of integrity, or lack of such. You sure you want to follow the troll into this realm, Floyd? Attacking my character... not too bright. You know I work on state of the art equipment, right? I help keep people like you safe.
[toc] | [prev] | [next] | [standalone]
| From | mechanic <mechanic@example.net> |
|---|---|
| Date | 2014-03-14 11:31 +0000 |
| Message-ID | <tlvscfp8whx4.dlg@example1357.net> |
| In reply to | #2834 |
On Thu, 13 Mar 2014 22:59:18 -0700, DecadentLinuxUserNumeroUno wrote: > You know I work on state of the art equipment, right? > > I help keep people like you safe. Isn't there a famous scene in some Apollo film where a visitor to NASA asks a cleaner in a corridor: "And what do you do here", the response was "I'm sending a man to the Moon!" Eerily familiar.
[toc] | [prev] | [next] | [standalone]
| From | DecadentLinuxUserNumeroUno <DLU1@DecadentLinuxUser.org> |
|---|---|
| Date | 2014-03-14 21:50 -0700 |
| Message-ID | <lpm7i9l8mm83ap0gkcna2krsv9dbe5nn33@4ax.com> |
| In reply to | #2835 |
On Fri, 14 Mar 2014 11:31:21 +0000, mechanic <mechanic@example.net> Gave us: >On Thu, 13 Mar 2014 22:59:18 -0700, DecadentLinuxUserNumeroUno >wrote: > >> You know I work on state of the art equipment, right? >> >> I help keep people like you safe. > >Isn't there a famous scene in some Apollo film where a visitor to >NASA asks a cleaner in a corridor: "And what do you do here", the >response was "I'm sending a man to the Moon!" > >Eerily familiar. Yet I still get the feeling from each post you make that you are eerily retarded. Trust me, pal, my baseband gateways are the best wireless devices on the planet surface. Even the big players in Europe, asia and australia are buying our gear. That is just the gear that I am able to discuss. You lose... again.
[toc] | [prev] | [next] | [standalone]
| From | floyd@apaflo.com (Floyd L. Davidson) |
|---|---|
| Date | 2014-03-14 04:31 -0800 |
| Message-ID | <87r465j721.fld@apaflo.com> |
| In reply to | #2834 |
DecadentLinuxUserNumeroUno <DLU1@DecadentLinuxUser.org> wrote: >On Thu, 13 Mar 2014 20:30:35 -0800, floyd@apaflo.com (Floyd L. Davidson) >Gave us: >>Do you know what "latency" means. > > Is that a question? No. >> A test does not have latency >>any more than a cable does. > > The test(s) utilize timing differences to make the aforementioned >determinations. Timing differences is not latency and interface hardware does not make such tests. The signal *delay* through an interface is "latency", and it has virtually nothing (measurable) to do with the twist of the cable pairs. That is for the simple reason that variations in the rather huge by comparison latency of other parts of a transmission system would make such measurements impossible without significant expense. That is, yes the effect of different twist can be measured but the test setup will cost thousands of dollars per cable segment to do it. A million dollar network becomes a billion dollar network... >>> Mustn't put badly fabbed cables into the system. Then it would be appropriate to purchase and use the test equipment required to assure cables meet specifications. >>> >>> Nice pass on backing up Bell. >> >>Poor digression on your part, > > Where? You mentioned an asshole and described him like he was some >fucking god. > > I mentioned that he was an asshole, and you didn't even retort. I >guess I wouldn't want you in the same foxhole as I. I wont digress to >relinquishment of trust. Digression, my ass. It's a digression when you go off topic to something that has no significance, express yourself in an extremely crude and rude way for no purpose other than your own emotional satisfaction. My reference to Bell had logical significance to the discussion, yours was only emotional and only to you. >> but it does demonstrate a certain >>level of integrity, or lack of such. > > You sure you want to follow the troll into this realm, Floyd? Well, as you noted above, I "didn't even retort". I have no reason to follow you into that realm. > Attacking my character... not too bright. > > You know I work on state of the art equipment, right? > > I help keep people like you safe. That may be, but I certainly am not aware of whether you do or don't. What is very clear is that you do not have technical knowledge of the equipment we are discussing. That doesn't prevent you from using it to a purpose, or suggest that you don't have operational skills, but it limits your credibility in describing it's functionality. Using the equipment is one thing, designing or trouble shooting its function is something very different. As others have alluded, the janitor may not be a design engineer, but he will have exactly the same mission goal! -- Floyd L. Davidson http://www.apaflo.com/ Ukpeagvik (Barrow, Alaska) floyd@apaflo.com
[toc] | [prev] | [next] | [standalone]
| From | mechanic <mechanic@example.net> |
|---|---|
| Date | 2014-03-14 13:45 +0000 |
| Message-ID | <12egoeyciezgx$.dlg@example1357.net> |
| In reply to | #2836 |
On Fri, 14 Mar 2014 04:31:02 -0800, Floyd L. Davidson wrote: > As others have alluded, the janitor may not be a design > engineer, but he will have exactly the same mission goal! Yes there's nothing wrong with that as that kind of community spirit raises morale in the team, and makes clear what it is that gets them out of bed in the morning. As to this twisted pair thing, I've no idea what the specs are in particular cables but no-one seems to have mentioned the purpose of such a feature (if indeed it exists) - presumably to reduce crosstalk between pairs, but is that important in Ethernet applications?
[toc] | [prev] | [next] | [standalone]
| From | floyd@apaflo.com (Floyd L. Davidson) |
|---|---|
| Date | 2014-03-14 07:26 -0800 |
| Message-ID | <87eh24kdih.fld@apaflo.com> |
| In reply to | #2837 |
mechanic <mechanic@example.net> wrote: >On Fri, 14 Mar 2014 04:31:02 -0800, Floyd L. Davidson wrote: > >> As others have alluded, the janitor may not be a design >> engineer, but he will have exactly the same mission goal! > >Yes there's nothing wrong with that as that kind of community spirit >raises morale in the team, and makes clear what it is that gets them >out of bed in the morning. Yep. Maybe design engineers are more critical, and higher paid, but the janitor really does contribute to the mission too! >As to this twisted pair thing, I've no idea what the specs are in >particular cables but no-one seems to have mentioned the purpose of >such a feature (if indeed it exists) - presumably to reduce >crosstalk between pairs, but is that important in Ethernet >applications? Crosstalk between pairs is the main issue with higher speed networking! Almost every difference between a modern CAT5 or CAT6 cable and the typical twisted pair drop cable used for a telephone 100 years ago is specifically intended to increase the speed of data by reducing crosstalk. But... the network interface does not do standards compliance testing! A network interface today is dime-a-dozen mass produced drop in device. The test equipment required to do such testing is not inexpensive. It is probably also worth noting that such test equipment does not measure or even indicate what the twist rate is on a pair. It just measures crosstalk levels and indicates a pass/fail condition, but not a reason for either. If a given cable segment fails though, other tests are available which might (or not) indicate a reason. Time Domain Reflectometry testing can show "impedance bumps" at a given distance from the end of a cable. But again, it doesn't indicate why there is an anomaly. A cable might have been spliced, it might have a bad connection, it might be crimped, it might have a poorly fabricated connector, etc etc. Any of those will show up as a point where the impedance is out of specifications, and it requires a visual inspection to determine what physical the cause is. -- Floyd L. Davidson http://www.apaflo.com/ Ukpeagvik (Barrow, Alaska) floyd@apaflo.com
[toc] | [prev] | [next] | [standalone]
| From | John Hasler <jhasler@newsguy.com> |
|---|---|
| Date | 2014-03-14 11:07 -0500 |
| Message-ID | <87ha70g3x4.fsf@thumper.dhh.gt.org> |
| In reply to | #2838 |
mechanic wrote: > As to this twisted pair thing, I've no idea what the specs are in > particular cables but no-one seems to have mentioned the purpose of > such a feature (if indeed it exists) - presumably to reduce crosstalk > between pairs, but is that important in Ethernet applications? Think about two twisted pairs running close together for a long distance. The field is not confined between the wires in a pair: a bit leaks out into the surrounding space. If there is another pair close by the field couples a bit of the signal into it. If the pairs have exactly the same twist rate this coupled interference will always be in the same phase and so will add up over a long run and cause problems. If the twist rates are slightly different the interference will vary in phase by 180 degrees over a length proportional to the difference in twist rate and so will average to zero. The problem gets worse at higher frequency so Ethernet is more sensitive to it. This effect was observed (and dealt with) in long 600 ohm open wire lines more than 100 years ago. -- John Hasler jhasler@newsguy.com Dancing Horse Hill Elmwood, WI USA
[toc] | [prev] | [next] | [standalone]
| From | floyd@apaflo.com (Floyd L. Davidson) |
|---|---|
| Date | 2014-03-14 10:23 -0800 |
| Message-ID | <8761ngk5ao.fld@apaflo.com> |
| In reply to | #2839 |
John Hasler <jhasler@newsguy.com> wrote: >mechanic wrote: >> As to this twisted pair thing, I've no idea what the specs are in >> particular cables but no-one seems to have mentioned the purpose of >> such a feature (if indeed it exists) - presumably to reduce crosstalk >> between pairs, but is that important in Ethernet applications? > >Think about two twisted pairs running close together for a long >distance. The field is not confined between the wires in a pair: a bit >leaks out into the surrounding space. If there is another pair close by >the field couples a bit of the signal into it. Up to this point that is correct. >If the pairs have >exactly the same twist rate this coupled interference will always be in >the same phase and so will add up over a long run and cause problems. The twist rate will not change the phase of the signal, either in the wire or induced into an adjacent wire, to any significant degree. >If the twist rates are slightly different the interference will vary in >phase by 180 degrees over a length proportional to the difference in >twist rate and so will average to zero. The problem gets worse at >higher frequency so Ethernet is more sensitive to it. While that change in phase rate will happen, it will not average to zero at any point in time at the cable termination. It will average to zero over a period of time, which is not useful >This effect was observed (and dealt with) in long 600 ohm open wire >lines more than 100 years ago. That's not the significance though. Phase makes exactly zero difference in regard common mode rejection of induced noise. If the signals have a given phase relationship it will remain exactly the same as long as the *length* of each pair is the same. The problem with having two pairs with the same twist is that they can and will end up physically aligned in such a way that each tip, for example, will have the same proximity to the other tip over an extended distance that will not be on an average equal to the proximity to the other ring. Thus unequal voltages will be induced between the tip and ring of each pair. Because each pair has a differential signal, resulting in common mode rejection of induced voltages, the twist is there to ensure that exposure to both tip and ring is of equal intensity for any given external field. If a field, for example, extends along one inch of the pair, and the pair has 50 twists per inch, the exposure to the tip will be very close to exactly the same as to the ring. Without the twist the field would be closer to one wire than to the other, and the induced voltages would be different. If the source of a field is another pair though, having the same twist would allow the wires to have the same unequal exposure tip to tip over an extended distance because a twist in one pair would match the twist, and distance, to the other pair. By using a different twist in each pair there will be a varying exposure over a significant distance, and that will cancel out the unequal exposure over any short distance. It is purely the strength of the signal induced, which is a function of distance. Other variations could affect it, but the cable is of course manufactured to minimize the significance of any other variation. Thickness and composition of insulation are examples where uniformity is important. -- Floyd L. Davidson http://www.apaflo.com/ Ukpeagvik (Barrow, Alaska) floyd@apaflo.com
[toc] | [prev] | [next] | [standalone]
Page 2 of 4 — ← Prev page 1 [2] 3 4 Next page →
Back to top | Article view | comp.os.linux.networking
csiph-web