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Re: My network speed is only 10MB



On Sat, 04 Feb 2012 23:12:22 -0800, D.G. Gómez wrote:

> On Sat, 04 Feb 2012 10:36:04 -0600, John Hasler wrote:
>>> Stan Hoeppner writes:
>>>> In the US, in the case of environments such as manufacturing floors
>>>> etc with horrific EMI levels, fiber is used instead of UTP CAT5/6.
>>>> With EFI levels that high, even STP won't save you.
>>> 
>>> STP can make things worse as almost nobody knows how to terminate
>>> shields in such a way as to avoid ground loops.
>> That's no longer true :-)
> 
> 
> 
>> And here it is a good article explaining the shielding advantadges:
> 
>> ***
>> Why shielded twisted-pair matters for 10GBase-T 
>> http://www.cablinginstall.com/index/display/article-display/279393/articles/cabling-installation-maintenance/volume-14/issue-12/features/design/why-shielded-twisted-pair-matters-for-10gbase-t.html
>> ***
> 
> That is a very old *advertisement*

It was dated on December, 2006 so it's not that old.

Advertisement? It can be, but based on facts and studies.

There are more technical readings at the IEEE site if you have access to 
them:

***
http://ieeexplore.ieee.org/search/freesrchabstract.jsp?tp=&arnumber=950524&openedRefinements%3D*%26filter%3DAND%28NOT%284283010803%29%29%26searchField%3DSearch+All%26queryText%3DUTP+and+STP

Abstract

The respective pros and cons of shielded (STP) and unshielded (UTP) 
twisted pairs are reviewed. Besides their lower cost, the hidden 
advantages of UTP are a slightly better balancing and a simpler connector 
hardware. Their balancing and common mode (CM) rejection can even be 
improved by high quality differential transformers with integrated CM 
blocking chokes. However when it comes to immunity to severe RF fields 
and to kilovolt electrical fast transients (EFT), UTP cannot achieve the 
necessary decoupling for mast typical high speed bus applications. This 
paper calculates the various emission and immunity features of modern UTP 
and STP, for a quantitative comparison
***

> Here are some modern references that are not from people with a lot of
> old IBM type 1 cable they try to sell.
> 
> http://www.utp-vs-stp.com/web/Microsites/UTP-vs-STP/

He, it seems that your know nothing about TE, it's a Tyco Electronics division, 
the same whose one of their engineers wrote the above referenced 
"old advertisement" in favor of the shielded cables ;-)

> http://www.exergia.info/Lightning/lightning4.htm

What the...! Modern!? This is an article of November 1994 :-D

Hint: it's better that you first *read* the articles you are defending.

> No modern company/university/department/business use STP.

That can be your experience, not mine.

> Maybe in Malaga, where they nail cable to trees :-) You make Spain sound
> backward. Not true.

What are you talking about? Are you kidding? What makes you think installing 
shielded LAN cables is something bad? :-?

> Expansys and DTT Global Networking Solutions are the o biggest cable
> companies in Spain (and Europe). I can tell you they rarely see STP
> except to remove it or for 10 year ago for outdoors. Even outdoors
> between buildings it is fibre now. In ceilings near fluorescents just
> use J hooks and run perpendicular - but usually always fibre unless
> homemade installer.

It can be for *big* companies or institutions (0.12%). I hope you know 99.8% 
of the companies in Spain are PYMES (Small and Medium Enterprises) that is, 
companies with less that 250 workers. And 53.9% of these companies have no 
workers at all! What makes you think this people is going to spend a penny 
in fiber?
 
> I think you do not represent most business.

Sure not! Most of the business here in Spain are still installing utp cat5e 
for getting "gigabit" speeds. And then they complaint about it...

My guess is that you don't know what are you talking about.

Greetings,

-- 
Camaleón


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