Two Ethernet Conns over one CAT5E

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

"Geoff" <geoff@nospam.demon.co.uk> wrote in message
news:Xns95B2E882B8C42geoffmailnews@158.152.254.254...
>I am looking for folks experience running two 100baseT full duplex links
> down about 50 metres of CAT5E by using the second two pair. It would be
> difficult to run a second CAT5E at this time.
>
> OK, I have done this using 10baseT half duplex with no detectable problems
> but has anybody done it at 100MHz full duplex?
>
> I think it should work, after all the crostalk level must be similar
> (+3dB)
> to a single full duplex link.
>
> --
> Geoff

100baseT requires the use of all four pairs, whereas 10baseT requires only
two of the four pairs.

S

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

ABC wrote:

(snip regarding two 100baseT connections on a four pair cable)

> 100baseT requires the use of all four pairs, whereas 10baseT requires only
> two of the four pairs.

Well, you should be a little more specific. The 100baseVG and
100baseT4 protocols use four pairs, but your chance of running
into them is extremely small. (Slightly better than winning
the state lottery.)

100baseTX uses two pairs. 1000baseT does use four pairs.

It will likely work fine, though I would try to keep well
below 100m. 50m sounds fine to me. It would be best to
wire the jacks in the normal manner and split after coming
out of the jacks. There are splitters similar to those
used for two line phones. If you have a crimper you
could crimp two cables into a single plug. I would only
recommend the latter for a home or other low budget application
such as a K-12 school.

For a commercial installation be sure to label it well so
that future network administrators know what is in place.

-- glen

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

In article <Xns95B2E882B8C42geoffmailnews@158.152.254.254>,
Geoff <geoff@nospam.demon.co.uk> writes:
>I am looking for folks experience running two 100baseT full duplex links
>down about 50 metres of CAT5E by using the second two pair. It would be
>difficult to run a second CAT5E at this time.
>
>OK, I have done this using 10baseT half duplex with no detectable problems
>but has anybody done it at 100MHz full duplex?

Yes, on several occasions.
>
>I think it should work, after all the crostalk level must be similar (+3dB)
>to a single full duplex link.
>
Indeed, running FE twice is no worse than 1000BaseT on all four pairs.

--
Manfred Kwiatkowski kwiatkowski@zrz.tu-berlin.de

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

ABC wrote:
>
>
> 100baseT requires the use of all four pairs, whereas 10baseT requires only
> two of the four pairs.
>
> S

WRONG. 100baset uses only the orange and green. VGAnylan 100mb ethernet
and 100TX both use 4 pairs, but not 100baseT

I run 2 100baseT on one cat5 all the time.

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

T. Sean Weintz wrote:
> ABC wrote:
>
>>
>>
>> 100baseT requires the use of all four pairs, whereas 10baseT requires
>> only two of the four pairs.
>>
>> S
>
>
> WRONG. 100baset uses only the orange and green. VGAnylan 100mb ethernet
> and 100TX both use 4 pairs, but not 100baseT
>
> I run 2 100baseT on one cat5 all the time.
oops. That reference to 100tx should read 100t4. I type to carelessly!

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

"T. Sean Weintz" <strap@hanh-ct.org> wrote in
news:10qud55tbommn07@news.supernews.com:

> ABC wrote:
>>
>>
>> 100baseT requires the use of all four pairs, whereas 10baseT requires
>> only two of the four pairs.
>>
>> S
>
> WRONG. 100baset uses only the orange and green. VGAnylan 100mb
> ethernet and 100TX both use 4 pairs, but not 100baseT
>
> I run 2 100baseT on one cat5 all the time.

Thanks folks for the confirmatory replies, ABC's reply threw me for a
moment :-). This is for home use and is to run two extra links to the
shed/workshop at the bottom of the garden (I have two 10baseT (but CAT5E)
cables out there but I want to run four off 10/100baseT connects.

TTFN

Geoff

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

Geoff <geoff@nospam.demon.co.uk> wrote:
> Thanks folks for the confirmatory replies, ABC's reply threw
> me for a moment :-). This is for home use and is to run two
> extra links to the shed/workshop at the bottom of the garden
> (I have two 10baseT (but CAT5E) cables out there but I want
> to run four off 10/100baseT connects.

Maybe it would be better to add a small 4 port hub.
Also give some isolation from lightening damage.

Running copper ethernet between buildings is always risky, moreso
if the satellite building has a subpanel and ground stake. I don't
know what UK practice is with ring mains and such. I presume
the shed has power, neutral & ground fed from the main building.

-- Robert

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

Geoff <geoff@nospam.demon.co.uk> writes:

> I am looking for folks experience running two 100baseT full duplex links
> down about 50 metres of CAT5E by using the second two pair. It would be
> difficult to run a second CAT5E at this time.
>
> OK, I have done this using 10baseT half duplex with no detectable problems
> but has anybody done it at 100MHz full duplex?
>
> I think it should work, after all the crostalk level must be similar (+3dB)
> to a single full duplex link.

Better to use it for gigabit and fan out at each end.

John

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

Geoff wrote:


> I am looking for folks experience running two 100baseT full duplex links

> down about 50 metres of CAT5E by using the second two pair. It would be

> difficult to run a second CAT5E at this time.

> OK, I have done this using 10baseT half duplex with no detectable
> problems
> but has anybody done it at 100MHz full duplex?

> I think it should work, after all the crostalk level must be similar
> (+3dB)
> to a single full duplex link.

It's not recommended, but if you have to do that as a last resort, here
are the pinouts and color codes for the split cable:

http://www.cabling-design.com/references/pinouts/split....

Good luck!

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

A better solution would be to get a couple of inexpensive ethernet switches
at both ends and that way you have room to grow beyond the 2nd link you are
describing and maintain a proper connection without rigging it.


"Geoff" <geoff@nospam.demon.co.uk> wrote in message
news:Xns95B2E882B8C42geoffmailnews@158.152.254.254...
>I am looking for folks experience running two 100baseT full duplex links
> down about 50 metres of CAT5E by using the second two pair. It would be
> difficult to run a second CAT5E at this time.
>
> OK, I have done this using 10baseT half duplex with no detectable problems
> but has anybody done it at 100MHz full duplex?
>
> I think it should work, after all the crostalk level must be similar
> (+3dB)
> to a single full duplex link.
>
> --
> Geoff