Muni fiber: L1 or L2?

Scott Helms khelms at zcorum.com
Sun Feb 3 01:06:06 UTC 2013


Owen,
I think the confusion I have is that you seem to want to create solutions
for problems that have already been solved.   There is no cost effective
method of sharing a network at layer 1 since DWDM is expensive and requires
compatible gear on both sides and no one has enough fiber (nor is cheap
enough in brand new builds) to simply home run every home and maintain
that.  ISPs that would want to use the shared network in general (>95% in
my experience) don't want to maintain the access gear and since there is no
clear way to delineate responsibilities when there is an issue its hard.


The long and short of it is lots of people have tried to L1 sharing and its
not economical and nothing I've seen here or elsewhere changes that.  The
thing you have to remember is that muni networks have to be cost effective
and that's not just the capital costs.  The operational cost in the long
term is much greater than the cost of initial gear and fiber install.
On Feb 2, 2013 4:54 PM, "Owen DeLong" <owen at delong.com> wrote:

> It seems that you are (deliberately or otherwise) seriously misconstruing
> what I am saying.
>
> I'm saying that if you build an L1 dark fiber system as we have described,
> the purchasers can use it to deploy Ethernet, PON, or any other technology.
>
> I'm not saying it's how I would build out a PON only system. That was
> never the goal.
>
> The goal is to provide a municipal L1 service that can be used by ANY
> provider for ANY service, or as close to that as possible.
>
> To make the offering more attractive to low-budget providers, the system
> may also incorporate some L2 services.
>
> Owen
>
> On Feb 2, 2013, at 1:31 PM, Scott Helms <khelms at zcorum.com> wrote:
>
> Owen,
>
> Cross connecting at layer 1 is what I'm saying isn't feasible.  If you
> want to simply hand them a fiber then sell dark fiber or DWDM ports but
> trying to create an architecture around PON or other splitters won't work
> because PON splitters aren't compatible with other protocols.
>
>
> On Sat, Feb 2, 2013 at 4:26 PM, Owen DeLong <owen at delong.com> wrote:
>
>>
>> On Feb 2, 2013, at 12:07 PM, Scott Helms <khelms at zcorum.com> wrote:
>>
>> Owen,
>>
>> A layer 1 architecture isn't going to be an economical option for the
>> foreseeable future so opining on its value is a waste of time...its simple
>> not feasible now or even 5 years from now because of costs.  The optimal
>> open access network (with current or near future technology) is well known.
>>  Its called Ethernet and the methods to do triple play and open access are
>> well documented not to mention already in wide spread use. Trying to
>> enforce a layer 1 approach would be more expensive than the attempts to
>> make this work with Packet Over SONET or even ATM.
>>
>> What is about a normal Ethernet deployment that you see as a negative?
>>  What problem are you tying to solve?
>>
>>
>> Ethernet works just fine in the L1 solution I've proposed, so I'm not
>> sure why you say it isn't economically viable to do so.
>>
>> Owen
>>
>>
>> On Sat, Feb 2, 2013 at 1:04 PM, Owen DeLong <owen at delong.com> wrote:
>>
>>>
>>> On Feb 2, 2013, at 2:19 AM, Eugen Leitl <eugen at leitl.org> wrote:
>>>
>>> > On Fri, Feb 01, 2013 at 04:43:56PM -0800, Leo Bicknell wrote:
>>> >
>>> >> The only place PON made any sense to me was extreme rural areas.
>>> >> If you could go 20km to a splitter and then hit 32 homes ~1km away
>>> >> (52km fiber pair length total), that was a win.  If the homes are
>>> >> 2km from the CO, 32 pair (64km fiber pair length total) of home
>>> >> runs was cheaper than the savings on fiber, and then the cost of
>>> >> GPON splitters and equipment.  I'm trying to figure out if my
>>> assessment
>>> >> is correct or not...
>>> >
>>> > Is there any specific reason why muni networks don't use 1-10 GBit
>>> > fiber mesh, using L3 switches in DSLAMs on every street corner?
>>>
>>> Well, one reason is that, IMHO, the goal here is to provide a flexible
>>> L1 platform that will allow multiple competing providers a low barrier
>>> to entry to provide a multitude of competitive services.
>>>
>>> Owen
>>>
>>>
>>>
>>
>>
>> --
>> Scott Helms
>> Vice President of Technology
>> ZCorum
>> (678) 507-5000
>> --------------------------------
>> http://twitter.com/kscotthelms
>> --------------------------------
>>
>>
>>
>
>
> --
> Scott Helms
> Vice President of Technology
> ZCorum
> (678) 507-5000
> --------------------------------
> http://twitter.com/kscotthelms
> --------------------------------
>
>
>



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