Luke Marrott wrote:
I'm wondering what everyones thoughts are in regards to FTTH using Active
Ethernet or Passive. I work for a FTTH Provider that has done Active
Ethernet on a few networks so I'm always biased in discussions, but I don't
know anyone with experience in PON.
Active is the way to go. Passive is merely a stepping stone on the way
to active. Passive only makes sense (in some cases) if you are 1) fiber
poor and 2) not doing a greenfield deployment. If you have the fiber to
work with or if you are building a FTTH plant from scratch go with
active. The only real proponents of PONs are the RBOCs who are
exceedingly cheap, slow to react, and completely unable to think ahead
(ie, putting in an abundance of fiber for future use instead of just
enough to get by) and some MSOs who don't dread and loathe shared
network mediums like CATV and PON (whereas those from a networking
background would never ever pick such a technology).
I've read before that almost all PON technology is proprietary, locking you
into a specific hardware vendor. However I think this is changing or has
already changed, opening PON up for interoperability. Can anyone confirm
this?
There are several actual PON standards out there:
http://en.wikipedia.org/wiki/Passive_optical_network
Few vendors will ever admit that they interop with another vendor's gear
though. They don't want you to buy their optical switches (which have a
small markup) and someone else's ONTs (which typically have a much
greater markup). In some cases even though that adhere to the standards
to a point they diverge and go proprietary for things like integrating
voice or video into the system. That could cause management and/or
support issues for you at some point in the life of the product.
Personally I'd go with a vendor that offers the complete solution
instead of piecing one together.
PON has some popularity in MDUs. The splits are easy to manage because
they're all in one location. Bandwidth needs are typically on the low
end in MDUs due to a lack of businesses (bandwidth being a severe
future-proofing problem for PON). PON's biggest limitations for us is
the distance limitations. We're deploying FTTH in the rural
countryside, not in a dense residential neighborhood. PON has very
specific distance limitations for each split and cumulative across all
splits that make rural deployments extremely difficult. The price
difference between Active and PON is negligible at this point and in
many cases cheaper for active. Go with active for FTTH. You won't
regret it.
Justin
