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Re: Does FiOS support rotary phones? [telecom]

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In article <ipbu08$72m$1@reader1.panix.com>,
Thor Lancelot Simon <tls@panix.com> wrote:
>
>not know but would tend to speculate likely not.  I believe there
>is really, truly, a 300 fiber bundle running in from the street and
>that it's not actively multiplexed until that location.  Maybe
>there are totally passive ways to do DWDM now so the passive "hubs"
>in the building actually have unpowered frequency multipliers/dividers
>in them -- I do not know.

I have looked into this a bit more; the above is not really correct in
two important respects.

1) The fiber "hubs" used by Verizon appear to be passive optical
   beam splitters/combiners.  The network is fully broadcast for
   downstream communications with a link layer beneath any standard
   Ethernet framing that emulates point-to-point Ethernet behavior
   (it would certainly seem that since there is a single downstream
   transmitter collisions really aren't possible so this should not
   be hard).  Downstream transmissions are encrypted so that, in theory,
   only a specific ONT can decrypt them.

   Upstream is a little funny.  The upstream signal supposedly
   propagates only towards the head end (how this is done optically
   I do not know but I'm sure it's possible), so encryption is not
   used.  I don't know how the head end handles collisions though
   it appears TDM in the upstream direction is used to attempt to
   assure they do not occur.

2) Fully passive DWDM/CWDM equipment is, in fact, available from several
   suppliers, but use of it in a PON deployment such as FiOS would be,
   at least, not something that is standardized.

So, the diagram I have that shows VZ entering the building in question
with two fibers -- not 300 -- is almost certainly correct in that detail,
and I was speaking whereof I knew not.

-- 
Thor Lancelot Simon	                                         tls@panix.com
    And now he couldn't remember when this passion had flown, leaving him so
  foolish and bewildered and astray: can any man?
						   William Styron

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Thread

Does FiOS support rotary phones? [telecom] "AJB Consulting" <ajbcs@frontier.com> - 2011-04-02 19:01 -0400
  Re: Does FiOS support rotary phones? [telecom] moroney@world.std.spaamtrap.com (Michael Moroney) - 2011-04-04 02:44 +0000
  Re: Does FiOS support rotary phones?  [telecom] John Stahl <aljon@stny.rr.com> - 2011-04-04 07:13 -0400
    Re: Does FiOS support rotary phones?  [telecom] T <kd1s.nospam@cox.nospam.net> - 2011-04-11 07:51 -0400
  Re: Does FiOS support rotary phones? [telecom] David Lesher <wb8foz@panix.com> - 2011-04-04 16:38 +0000
    Re: Does FiOS support rotary phones? [telecom] "Gary" <bogus-email@hotmail.com> - 2011-04-10 14:10 -0400
    Re: Does FiOS support rotary phones? [telecom] tls@panix.com (Thor Lancelot Simon) - 2011-04-30 13:02 +0000
      Re: Does FiOS support rotary phones? [telecom] "D. W." <indianut@gmail.com> - 2011-06-07 15:39 -0700
    Re: Does FiOS support rotary phones? [telecom] tls@panix.com (Thor Lancelot Simon) - 2011-04-28 14:37 +0000
      Re: Does FiOS support rotary phones? [telecom] T <kd1s.nospam@cox.nospam.net> - 2011-04-29 19:15 -0400
  Re: Does FiOS support rotary phones? [telecom] "Gary" <bogus-email@hotmail.com> - 2011-04-10 14:30 -0400
  Re: Does FiOS support rotary phones? [telecom] tls@panix.com (Thor Lancelot Simon) - 2011-04-28 14:35 +0000
    Re: Does FiOS support rotary phones? [telecom] tls@panix.com (Thor Lancelot Simon) - 2011-04-28 15:55 +0000

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