Electrical Speciations for 100BaseT Ethernet

Electrical Speciations for 100BaseT Ethernet

Post by nige » Tue, 01 Jul 2003 11:50:07



Hi!

Where can I find Electrical Speciation for 100 BaseT Ethernet. I want to know what voltage and current it uses.

Is it a Current driven network or Voltage like the old coaxial Ethernet.

Is it a current loop system?

What are the nominal electrical values.

Thanks in Advanced!

Nigel

 
 
 

Electrical Speciations for 100BaseT Ethernet

Post by Marri » Wed, 02 Jul 2003 06:26:13


Nigel,
   Try

  http://standards.ieee.org/getieee802/

or

 http://standards.ieee.org/getieee802/portfolio.html

and select 802.3

to get to

 http://standards.ieee.org/getieee802/802.3.html


  Hi!

  Where can I find Electrical Speciation for 100 BaseT Ethernet. I want to know what voltage and current it uses.

  Is it a Current driven network or Voltage like the old coaxial Ethernet.

  Is it a current loop system?

  What are the nominal electrical values.

  Thanks in Advanced!

  Nigel

 
 
 

Electrical Speciations for 100BaseT Ethernet

Post by Rich Seifer » Mon, 07 Jul 2003 08:56:25




>    Try

>   http://standards.ieee.org/getieee802/

> or

>  http://standards.ieee.org/getieee802/portfolio.html

> and select 802.3

> to get to

>  http://standards.ieee.org/getieee802/802.3.html



>   Hi!

>   Where can I find Electrical Speciation for 100 BaseT Ethernet. I want to
>   know what voltage and current it uses.

>   Is it a Current driven network or Voltage like the old coaxial Ethernet.

>   Is it a current loop system?

>   What are the nominal electrical values.

Actually, this is one of the few questions that would NOT be answered by
looking at the 802 spec. 100BASE-TX lifted the electrical specs from the
ANSI FDDI TP-PMD standard (ISO 9314). The 802 spec simply sends the
reader to the ISO document; the actual numbers are not reproduced.

The short answer is that 100BASE-TX uses a voltage source driver,
nominally +/- 1 V differential into a 100 ohm load.

--
Rich Seifert              Networks and Communications Consulting

(408) 395-5700            Los Gatos, CA 95033
(408) 395-1966 FAX

 
 
 

Electrical Speciations for 100BaseT Ethernet

Post by nige » Tue, 08 Jul 2003 12:27:41


Thank you!




> >    Try

> >   http://standards.ieee.org/getieee802/

> > or

> >  http://standards.ieee.org/getieee802/portfolio.html

> > and select 802.3

> > to get to

> >  http://standards.ieee.org/getieee802/802.3.html



> >   Hi!

> >   Where can I find Electrical Speciation for 100 BaseT Ethernet. I want
to
> >   know what voltage and current it uses.

> >   Is it a Current driven network or Voltage like the old coaxial
Ethernet.

> >   Is it a current loop system?

> >   What are the nominal electrical values.

> Actually, this is one of the few questions that would NOT be answered by
> looking at the 802 spec. 100BASE-TX lifted the electrical specs from the
> ANSI FDDI TP-PMD standard (ISO 9314). The 802 spec simply sends the
> reader to the ISO document; the actual numbers are not reproduced.

> The short answer is that 100BASE-TX uses a voltage source driver,
> nominally +/- 1 V differential into a 100 ohm load.

> --
> Rich Seifert              Networks and Communications Consulting

> (408) 395-5700            Los Gatos, CA 95033
> (408) 395-1966 FAX

 
 
 

1. Electrical specs/info for 10baseT and 100baseT...

Hi all,

I'm trying to find information on the electrical specifications of
10baseT and 100baseT ethernet - voltage/current threshholds, signaling
methods, etc. I've spent most of the night browsing, and it appears
that the best source for this is going to be the IEEE 802.3 standards
document.

While I order that, though, I figured I'd post a couple of questions
here, in the hopes that someone has the time to answer }:> .

What I gather so far as far as signaling goes is that there're
essentially three states. Dormant (no signal), a 0 bit (carrier pulse),
and a 1 bit (polarity-reversed carrier pulse). The link test piggybacks
(somehow) onto this.

Data signals occur at a maximum rate of 20 MHz. (I may have mixed
my units there, but the value seems right.)

The voltage is somewhere around 9V between the + and - data lines.

First question: Is there a better source for this sort of info than
the IEEE spec?

Second question: Is what I gather above about the signaling more or
less correct? Is there anything I'm missing?

Third question: if I understand right, there's no real need for
synchronization of the '20 MHz clocks', because the collision
detection takes care of worrying about that.

Fourth question: if I measure the number of carrier pulses (either
normal or reversed) on one of the data pairs over 1 second, will I
get a measure of the total amount of traffic on the segment (including
collision and link-test packets)?

Thanks for any information anyone can provide; I really appreciate it.

-dalvenjah
--
 Dalvenjah FoxFire (aka Sven Nielsen) "The weapon which causes the most
 Founder, the DALnet IRC Network       damage to the Internet is
                                       the keyboard."


 whois: SN90                           Try DALnet! http://www.dal.net/

2. . kbd-macro-query ?????

3. Q:Thin Ethernet cabling and electrical interference.

4. Problems running code 700 program on D.39

5. Can my Ethernet cable safely bundle with an electrical wire?

6. i don't like Bleem so far

7. Ethernet and electrical interference

8. Sharing Optimum Online instructions

9. electrical isolation, switches, ARP and ethernet over UTP

10. Home network -- distance between ethernet and electrical cables

11. Ethernet electrical signals...?

12. Ethernet electrical singals...