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RE: [10GBASE-T] The channel model





Terry:

IEEE Clause 52 for 10 GbE contains the following guidance relative to
environment:(Embedded image moved to file: pic08909.pcx)
(Embedded image moved to file: pic32209.pcx)
Copper cable appears more susceptible to environmental effects at the
frequencies required to operate at 10 GbE.  I encourage the 10GBASE-T group
to simply investigate the effect to make certain that copper transmission
systems are not compromised "over a reasonable range of environmental
conditions related to temperature, humidity..."  for 10 GbE systems.

Optical fiber and cable standards are referenced in Clause 52 that ensure
reliable operation "over a reasonable range of environmental conditions
related to temperature, humidity...."  I'd expect no less for copper media.

Doug








                                                                                                                                    
                    "Cobb, Terry R (Terry)"                                                                                         
                    <tcobb@avaya.com>                     To:     Doug.Coleman@corning.com, Chris DiMinico <cd@mohawk-cdt.com>      
                    Sent by:                              cc:     owner-stds-802-3-10gbt@majordomo.ieee.org, Roger Karam            
                    owner-stds-802-3-10gbt@majordom        <rkaram@cisco.com>, stds-802-3-10gbt@ieee.org, xichen@marvell.com        
                    o.ieee.org                            Subject:     RE: [10GBASE-T] The channel model                            
                                                                                                                                    
                                                                                                                                    
                    01/15/2003 10:04 AM                                                                                             
                                                                                                                                    
                                                                                                                                    





Doug,

As stated in all PHY's for 802.3 now (see Clause 40.9.3.2) and in the
future, "Specific requirements and values for environmental conditions are
considered to be beyond the scope of this standard."

As such temperature and humidity conditions will not be included in a
standard.

Terry

-----Original Message-----
From: Doug.Coleman@corning.com [mailto:Doug.Coleman@corning.com]
Sent: Wednesday, January 15, 2003 8:37 AM
To: Chris DiMinico
Cc: owner-stds-802-3-10gbt@majordomo.ieee.org; Roger Karam;
stds-802-3-10gbt@ieee.org; xichen@marvell.com
Subject: Re: [10GBASE-T] The channel model




Chris:

Attached is the TIA letter to ICEA justifying the need for the
environmental study of UTP.  An ICEA WG has been formed to address the
request.


(See attached file:
TR42_2002-06-047a_Liaison_Letter_to_ICEA_on_Environmentals.doc)

Regards,

Doug




                    Chris DiMinico
                    <cd@mohawk-cdt.com>                   To:
Doug.Coleman@corning.com
                    Sent by:                              cc:
owner-stds-802-3-10gbt@majordomo.ieee.org, Roger Karam
                    owner-stds-802-3-10gbt@majordom
<rkaram@cisco.com>, stds-802-3-10gbt@ieee.org, xichen@marvell.com
                    o.ieee.org                            Subject:     Re:
[10GBASE-T] The channel model


                    01/15/2003 09:13 AM







Doug,

ANSI/TIA/EIA-568-B.2-1-2002 -  Addendum 1 ? Transmission Performance
Specifications
for 4-pair 100 ohm Category 6 Cabling contains an informative annex (G)
addressing
cable installation in higher temperature environments. Examples of cable
length reductions based
on the specified  temperature de-rating are provided in a table.

I'd welcome other  input.

Regards,

Chris


----- Original Message -----
From: <Doug.Coleman@corning.com>
To: "Chris DiMinico" <cd@mohawk-cdt.com>
Cc: <owner-stds-802-3-10gbt@majordomo.ieee.org>; "Roger Karam" <
rkaram@cisco.com>;  <stds-802-3-10gbt@ieee.org>;  <xichen@marvell.com>
Sent: Wednesday, January 15, 2003 8:13  AM
Subject: Re: [10GBASE-T] The channel  model


>
>
> Chris:
>
> I encourage 10GBASE-T work  to include environmental effects
(temperature,
> humidity, etc..)  on  transmission performance.  ICEA is currently
> investigating  environmental effects on UTP cable based on a request from
> TIA.  A  constant benign +23C environment should not be assumed when
> generating  10 Gbe copper cable guidance.
>
> Regards,
>
> Doug  Coleman
> Corning Cable Systems
>
>
>
>
>                       Chris  DiMinico
>                       <cd@mohawk-cdt.com>                    To:
Roger Karam <rkaram@cisco.com>
>                       Sent  by:                               cc:
stds-802-3-10gbt@ieee.org, xichen@marvell.com
>                       owner-stds-802-3-10gbt@majordom       Subject:
Re:  [10GBASE-T] The channel  model
>                       o.ieee.org
>
>
>                       01/14/2003 04:46  PM
>
>
>
>
>
>
>
> Roger,
>
>  TIA requires that measurements be performed on cable samples
> removed  from the reel or packaging and laid out along a nonconducting
> surface,  loosely coiled, or supported in aerial spans, with all pairs
>  terminated.
> Modeling applies to this test configuations.
>
> Modeling "coiled" cable is as easy as power supply engineering.
>
> Regards,
>
> Chris
>
>
> -----  Original Message -----
> From: "Roger Karam" <rkaram@cisco.com>
> To:  "Chris DiMinico" <cd@mohawk-cdt.com>
> Cc:  <stds-802-3-10gbt@ieee.org>;  <xichen@marvell.com>
> Sent:  Tuesday, January 14, 2003 4:18 PM
> Subject: Re: [10GBASE-T] The channel  model
>
>
> >
> > Hi Chris,
> >
>  > Just how much fun is it to model the coiled and the 'not coiled'
cables?
> > roger
> >
> > At 12:38 PM 1/14/2003,  Chris DiMinico wrote:
> >
> > >Xiaopeng,
> >  >
> > >Worst case channel models for category cables are  specified in TIA
and
> ISO
> > >cabling standards.
>  > >Given that one of our objectives is to operate over ISO 11801 cabling
we
> > >should use the cabling
> > >standards (ISO and  TIA) channel specifications as our 10GBASE-T model
> > >baseline  (whenever
> > >possible).
> > >
> > >For  1000BASE-T, the channel models we used in the matlab simulations
> >  >consisted of measurements
> > >(magnitude and phase) of cabling  channels scaled to the envelope of
the
> > >worst case function  specified.
> > >
> > >
> > >Regards,
>  > >
> > >Chris
> > >
> > >
>  > >
> > >----- Original Message -----
> > >From:  <xichen@marvell.com>
> >  >To: <stds-802-3-10gbt@ieee.org>
>  > >Sent: Tuesday, January 14, 2003 2:44 PM
> > >Subject:  [10GBASE-T] The channel model
> > >
> > >
> >  > >
> > > > I would like to propose the following channel  and noise model.
Then
> we
> > > > can work  together to come up with a model that all of us agree on.
> > >  >
> > > > 1.  Channel insertion loss model: refer to the  RLCG model on page
47
> of
> > > > T1E1.4/2000-002R6.   Then calibrate the insertion loss (100m) at
> 100MHz
> to
>  > > > 21dB for CAT-6 and 24dB for CAT-5/5E.
> > >  >
> > > > 2. NEXT model:  ~f^(1.5)n^(0.6)  where n  is number of disturbers.
In
> our
> > > > case, n=3.   Then calibrate the NEXT at 100MHz to -31dB for CAT-5E
> > >and  -40dB
> > > > for CAT-6.
> > > >
> > >  > 3. ELFEXT model:  ~f^(2)n^(0.6)  where n is number of disturbers.
In
> our
> > > > case, n=3.  Then calibrate the ELFEXT  (100m) at 100MHz to -19dB
for
> CAT-5E
> > > > and -24dB  for CAT-6.
> > > >
> > > > 4. ANEXT model:
>  > > > CAT-5E: max[-65, -38+15log10(f/1e8)] dB
> > > >  CAT-6:  max[-65, -41+15log10(f/1e8)] dB
> > > >
> >  > > 5: Tranformer model: please contribute
> > > >
>  > > > Xiaopeng
> > > >
> > > >
>  > > >
> > > >
> > > >
>  >
> >
> >
>
>
>
>
>
>
>


pic08909.pcx

pic32209.pcx