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Re: [802.3BA] Longer OM3 Reach Objective


Looks like I pointed to the wrong IEEE com magazine, link below should 
take to
the right article.


Ali Ghiasi wrote:
> Jonathan
> In Jan 08 interim meeting I presented the following presentation
> and published in IEEE communication magazine:
> which showed even with a 4G transmitter a 300 m OM3 link has one dB 
> more margin
> using a simple EDC (Electronic Dispersion Compensation) compare to a 
> limiting link operating
> over 100 m of OM3 fiber, similar to:
> To meet IEEE objective to support copper cable for 10 operation, some 
> form of EDC
> would be required. As long as the copper and the optical 
> specifications for linear
> interface are not defined in orthogonal fashion, a port supporting 
> copper cable can greatly
> benefit a port supporting linear optics and extend the reach to 300 m!
> Previously when I stated the OM3 link can be extended to 300 m and 
> with increase link
> margin, the reply was there is no such application requirements.  It 
> is good to hear from
> people like you.
> Thanks,
> Ali
> Jonathan Jew wrote:
>> I am a consultant with over 25 years experience in data  center
>> infrastructure design and data center relocations including in excess 
>> of 50
>> data centers totaling 2 million+ sq ft.  I am currently engaged in data
>> center projects for one of the two top credit card processing firms 
>> and one
>> of the two top computer manufacturers.
>> I'm concerned about the 100m OM3 reach objective, as it does not 
>> cover an
>> adequate number (>95%) of backbone (access-to-distribution and
>> distribution-to-core switch) channels for most of my clients' data 
>> centers.
>> Based on a review of my current and past projects, I expect that a 
>> 150m or
>> larger reach objective would be more suitable.  It appears that some 
>> of the
>> data presented by others to the task force, such as Alan Flatman's Data
>> Centre Link Survey supports my impression.
>> There is a pretty strong correlation between the size of my clients' 
>> data
>> centers and the early adoption of new technologies such as higher 
>> speed LAN
>> connectivity.   It also stands to reason that larger data centers have
>> higher bandwidth needs, particularly at the network core.
>> I strongly encourage you to consider a longer OM3 reach objective 
>> than 100m.
>> Jonathan Jew
>> President
>> J&M Consultants, Inc
>> co-chair BICSI data center standards committee
>> vice-chair TIA TR-42.6 telecom administration subcommittee
>> vice-chair TIA TR-42.1.1 data center working group (during 
>> development of
>> TIA-942)
>> USTAG representative to ISO/IEC JTC 1 SC25 WG3 data center standard 
>> adhoc

fn:Ali Ghiasi
adr;dom:;;3151 Zanker Road;San Jose;CA;95014
title:Chief Architect