Hi, I've been reading a little about passive optic networks and the
idea is very good from my stand point.
As far as I have understood, the idea is to use the fiber as it was
coax, doing some kind of FDM (frequency division multiplexing) with
the lambdas (somehow the same). This would give us the capability
to move at leat n x 10mbps ethernet on the same fiber using diferent
lambdas for each customer, until power budget goes down.
If the idea is correct, this would mean "next jump" on bandwidth.
Who would be making this "ethernet/lambda multiplexors" right
now? Is it feasible to do it today? or should we wait a little more?
I mean, there are solutions using packet over sonet or alike, but
pure ethernet?
The units that I worked with in the past (from an outfit called Quantum
Bridge www.quantumbridge.com) worked pretty well, but the deployment model
didn't meet my emplolyer's biz model (since it required outside plant).
Basically the way it worked was it ran ATM OC-3 (mabe OC-12) down the
fiber, using passive optical splitters, to the CPE. The CPE used a TDM
style muxing for the return on a different lambda on the same fibre. The
CPE itself was interesting too. It provided a 100bt ethernet port (showed
up as and ATM pvc at the headend, with the actually allocated bandwidth
controllable from 1.5 to 100 megs, as well as 4 DS1 ports. The DS1s were
Circuit Emulated over the ATM fabric.
Concerptually it was very interesting, and I imagine other POS solutions
are similar, as simply using a lambda per customer would not be an
efficient utilization of the available bandwidth.
-Scott
www.carrieraccess.com makes PON CPE gear. http://www.carrieraccess.com/products/index.cfm/fuseaction/default_prod/cat_id/118.htm
www.alcatel.com makes PON 'head end' gear that works with CAC CPE.
Basically, 1 strand of fiber (not a pair) can be used for 16 or 32 customers and will handle up/down data, down video, up/down T1 for voice at the customer. Head end voice, video and data is split apart.
Carrier Access Corp hardware is rock solid, I have *never* had one fail. I don't use the PON stuff but I do use their DS1 & DS3 stuff.
-Matt
As far as I have understood, the idea is to use the fiber as it was
coax, doing some kind of FDM (frequency division multiplexing) with
the lambdas (somehow the same). This would give us the capability
In the optics field it is usually called WDM (Wavelenght Division
Multiplexing).
to move at leat n x 10mbps ethernet on the same fiber using diferent
lambdas for each customer, until power budget goes down.
Nope; PON works by sharing the same channel among the users. There is a WDM
use of the fiber only because the uplink and downlink use different
wavelenghts, but the downlink is shared with TDM (Time Division
Multiplexing) and the uplink with TDMA (TDM/Multiple Access).
If the idea is correct, this would mean "next jump" on bandwidth.
Who would be making this "ethernet/lambda multiplexors" right
now? Is it feasible to do it today? or should we wait a little more?
PONs are feasible today; the CO equipment is called OLT (Optical Line
Terminator), and the CPE is a ONT/ONU (Optical Network Terminator/Unit). The
only external device is a passive star coupler.
Check out www.ponforum.org, www.fsanweb.org and www.efma.org
I mean, there are solutions using packet over sonet or alike, but
pure ethernet?
PON has three flavors: APON/BPON, EPON (IEEE 802.3ah) and GPON. APON uses
ATM framing, EPON uses Ethernet framing and GPON uses GFP (Generic Framing
Protocol). GFP can also be used on top of SONET to make Ethernet-over-SONET,
Rubens
Dear Miguel;
Having heard no answer, I will take a shot :
I actually think that EPONs have a good chance to be the future method of distributing video from the "cable" provider to the home. As they are passive, it minimizes the amount of equipment out there. A 10-Gigabit Ethernet running multicast IP (probably with some form of packet tagging like MPLS) could more than support all of the video and data needs of a typical cable head-end customer base.
There is a PON forum
http://www.ponforum.org/presentations/page115.html
and also the fiber to the home council which seems to be hot on EPONs
You might look at alloptic as a equipment provider here
http://www.alloptic.com/
Hi, I've been reading a little about passive optic networks and the
idea is very good from my stand point.
As far as I have understood, the idea is to use the fiber as it was
coax, doing some kind of FDM (frequency division multiplexing) with
the lambdas (somehow the same). This would give us the capability
to move at leat n x 10mbps ethernet on the same fiber using diferent
lambdas for each customer, until power budget goes down.
If the idea is correct, this would mean "next jump" on bandwidth.
Who would be making this "ethernet/lambda multiplexors" right
now? Is it feasible to do it today? or should we wait a little more?
I mean, there are solutions using packet over sonet or alike, but
pure ethernet?
--
Miguel Mata-Cardona
Intercom El Salvador
mmata@intercom.com.sv
voz: ++(503) 278-5068
fax: ++(503) 265-7024
Regards
Marshall Eubanks
T.M. Eubanks
e-mail : tme@multicasttech.com
http://www.multicasttech.com
Test your network for multicast :
http://www.multicasttech.com/mt/
Our New Video Service is in Beta testing
http://www.americafree.tv
Having heard no answer, I will take a shot :
I actually think that EPONs have a good chance to be the future method
of distributing video from the "cable" provider to the home. As they
are passive, it minimizes the amount of equipment out there. A
May be not... all xPON systems have a wavelength window reserved for DWDM
broadcast, that seems more suited to the task.
10-Gigabit Ethernet running multicast IP (probably with some form of
packet tagging like MPLS) could more than support all of the video and
data needs of a typical cable head-end customer base.
EPON/IEEE 802.3ah is a 1-Gigabit system (actually a 1.25 Gbps but 20% is
used by the 8B10B encoding); I haven't seen any spec for a 10-Gig PON; even
recently standardized GPON is limited to 2.5 Gbps downlink, 1.25 Gbps
uplink.
You might look at alloptic as a equipment provider here
http://www.alloptic.com/
Or
http://www.alcatel.com/fttu
http://www.flexlight-networks.com/
http://www.teknovus.com
Rubens