1000 Base T

[Guest]

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What are the length requirements for 1000 base t cabling? I swapped
out a 10/100 hub for a 10/100/1000 hub and only a few ports are using
1000 even though all NICs are 10/100/1000.

 

[Guest]

Archived from groups: comp.dcom.lans.ethernet (More info?)

just1coder wrote:

> What are the length requirements for 1000 base t cabling? I swapped
> out a 10/100 hub for a 10/100/1000 hub and only a few ports are using
> 1000 even though all NICs are 10/100/1000.

Same as for 100TX--there are some additional tests that should be applied to
the cabling but any decent-quality cable that is properly installed that
passes CAT5 should pass 5E.

Get yourself a couple of SMC boards or others that are based on the Marvell
Yukon chips and run the cable analysis software that comes with them--if
there are any glaring problems with the cable that should find them.

--
--John
Reply to jclarke at ae tee tee global dot net
(was jclarke at eye bee em dot net)

 

[Guest]

Archived from groups: comp.dcom.lans.ethernet (More info?)

just1coder <just1coder@yahoo.ca> wrote:
> What are the length requirements for 1000 base t cabling? I
> swapped out a 10/100 hub for a 10/100/1000 hub and only a few
> ports are using 1000 even though all NICs are 10/100/1000.

100m (328ft), same as 100baseTX.

Are you sure all cabling is good (no split pairs, all 8 conductors
properly terminated)? Otherwise, it may be a software issue.

-- RObert

 

[Guest]

Archived from groups: comp.dcom.lans.ethernet (More info?)

Robert Redelmeier <redelm@ev1.net.invalid> wrote in message news:<I9A4d.23968$ec6.16488@newssvr24.news.prodigy.com>...
> just1coder <just1coder@yahoo.ca> wrote:
> > What are the length requirements for 1000 base t cabling? I
> > swapped out a 10/100 hub for a 10/100/1000 hub and only a few
> > ports are using 1000 even though all NICs are 10/100/1000.
>
> 100m (328ft), same as 100baseTX.
>
> Are you sure all cabling is good (no split pairs, all 8 conductors
> properly terminated)? Otherwise, it may be a software issue.
>
> -- RObert

Sorry, I meant the minimum length. They were all tested out on a 100
mbit switch when I cut them ... worked fine there ... figured they
would be OK on the 1000 mbit ... apparently not :|

 

[Stephen]

Archived from groups: comp.dcom.lans.ethernet (More info?)

"just1coder" <just1coder@yahoo.ca> wrote in message
news:de157e8c.0409230516.1590a172@posting.google.com...
> What are the length requirements for 1000 base t cabling? I swapped
> out a 10/100 hub for a 10/100/1000 hub and only a few ports are using
> 1000 even though all NICs are 10/100/1000.

the supported length is the same (100m or 90m fixed + 10m allowance for
patching) - as long as your cable is installed properly.

but 1000 Base-T needs all 4 pairs connected correctly, whereas 100 Base-TX
only needs 2.
--
Regards

Stephen Hope - return address needs fewer xxs

 

[Guest]

Archived from groups: comp.dcom.lans.ethernet (More info?)

just1coder <just1coder@yahoo.ca> wrote:
> Sorry, I meant the minimum length. They were all tested out on a
> 100 mbit switch when I cut them ... worked fine there ... figured
> they would be OK on the 1000 mbit ... apparently not :|

Cut them? Why? How did you reterminate? Punchdown or crimp?
Both have pitfalls.

There is _no_ minimum length for 100baseTX. I've used 1 cm
loopbacks and 5 cm crossovers successfully at full throughput.
AFAIK, the same goes for GBE.

-- Robert

 

[Guest]

Archived from groups: comp.dcom.lans.ethernet (More info?)

just1coder wrote:




> What are the length requirements for 1000 base t cabling? I swapped
> out a 10/100 hub for a 10/100/1000 hub and only a few ports are using
> 1000 even though all NICs are 10/100/1000.

When you switched from 10/100 to 1G and it stopped working (quality of
cabling presumably OK, except for wiremap), it normally means your pairs
#1 and #4 were terminated badly or not at all. 10/100 equipment can care
less about those pairs whereas Gigabit Ethernet needs all four.

--
Dmitri Abaimov, RCDD
http://www.cabling-design.com
Cabling Forum, color codes, pinouts and other useful resources for
premises cabling users and pros
http://www.cabling-design.com/homecabling
Residential Cabling Guide
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