Muni fiber: L1 or L2?

Fri Feb 1 03:21:23 UTC 2013

Fletcher nailed it, if you want the architecture you're describing then you
simply don't want PON.  Its built around lower cost and a big part of that
lower cost is minimizing the fiber costs by serving splitters (and thus
many homes) from a single fiber that back hauls to the CO.  The other
reason PON won't work for what you want is the splitters are passive and
completely static in their operation.  Here's an image of one that may make
this clearer:

http://media.wholesale-electrical-electronics.com/product/imgage/Electrical&Electronics/2010101220/6dc7c82d59d9fd931bfba560a3e85031.jpg

If you have to either run several (or more) fibers to a neighborhood or
have managed neighborhood elements then you've simply destroyed the use
case for PON.  Luckily this use case matches pretty exactly for Ethernet,
but you must do your wholesale play at layer 2 IMO to work economically.

On Thu, Jan 31, 2013 at 6:28 PM, Owen DeLong <owen at delong.com> wrote:

>
> On Jan 31, 2013, at 13:57 , Fletcher Kittredge <fkittred at gwi.net> wrote:
>
>
>
>
> On Thu, Jan 31, 2013 at 4:36 PM, Owen DeLong <owen at delong.com> wrote:
>
>> If you have an MMR where all of the customers come together, then you
>> can cross-connect all of $PROVIDER_1's customers to a splitter provided
>> by $PROVIDER_1 and cross connect all of $PROVIDER_2's customers to
>> a splitter provided by $PROVIDER_2, etc.
>>
>> If the splitter is out in the neighborhood, then $PROVIDER_1 and
>> $PROVIDER_2
>> and... all need to build out to every neighborhood.
>>
>> If you have the splitter next to the PON gear instead of next to the
>> subscribers,
>> then you remove the relevance of the inability to connect a splitter to
>> multiple
>> OLTs. The splitter becomes the provider interface to the open fiber plant
>
>
> Owen;
>
> Interesting.   Do you then lose the cost advantage because you need home
> run fiber back to the MMR?   Do you have examples of plants built with this
> architecture (I know of one such plant, but I am hoping you will turn up
> more examples.)
>
>
> I don't know of any. Yes, it would eliminate part of the theoretical cost
> savings of the PON architecture, but the point is that it would provide a
> technology agnostic last mile infrastructure that could easily be used by
> multiple competing providers and would not prevent a provider from using
> PON if they chose to do so for other reasons.
>
> Owen
>
>

-- 
Scott Helms
Vice President of Technology
ZCorum
(678) 507-5000
--------------------------------
http://twitter.com/kscotthelms
--------------------------------