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Re: DSL over Frame Relay [7:76443] posted 09/30/2003
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""Howard C. Berkowitz""  wrote in message
news:200309301242.h8UCgYMI009975@xxxxxxxxxxxxxxxxx
> At 10:45 AM +0000 9/30/03, nrf wrote:
> >""Steven Meier""  wrote in message
> >news:200309300327.h8U3RjUg031079@xxxxxxxxxxxxxxxxx
> >>  I must be thick......or having a blonde day...but DSL over frame relay
is
> >>  impossible as they are 2 different hardware transport platforms.
> >>
> >>  DSL is ATM and uses completely different hardware than a frame relay
> >circuit
> >>  which uses PVC's etc whether permanent or semi permanaent.
> >>
> >>  The packet structure is different as well.
> >>
> >>  or am I completely blonde.
> >
> >I don't want to comment on your hair-color, but you can indeed have DSL
over
> >frame-relay.  It's rare, but some DSLAM vendors support it.  While DSL is
> >usually backhauled through ATM, this is not necessarily so - any backhaul
> >mechanism can be used in theory.  It all depends on what the vendor
supports
> >and how the service-provider wants to build the network.
>
> Well, I confess to being confused by this thread, even though I'm
> more hair-challenged. I have no difficulty understanding the use of
> DSL as a first-mile access technology to FR, as ISDN, dial and even
> X.25 have been used for years.
>
> But DSL, to the best of my knowledge, is a physical layer
> specification, full of modulations, medium requirements, etc., that
> feeds bit streams into a DSLAM, which may pass along bit streams on
> ATM, or, if the DSLAM contains layer 2 or 3 functionality, pass
> frames or packets. ADSL, SDSL, ISDL, VHSDL, etc., don't specify
> frames, to the best of my knowledge.
>
> We speak glibly of Ethernet-over-whatever, but we really are speaking
> there of 802.3 frames, not Manchester-encoded baseband signals or
> optical or broadband equivalents, or the OC-192 PHY for 10 GE.
> DSL-over-whatever sounds like the equivalent of Manchester over
> frame, essentially an analog-to-digital process.
>
> Have people been using sloppy terminology or am I missing something
> fundamental?

Well, I don't know about other people here, but I can say that I am
purposefully using sloppy terminology.  Or, should I say, I am using very
loose, marketing-oriented definitions of technology.  Why am I doing this?
Because I recognized that the syntax of this thread was loose, so I
responded in kind.  When in Rome...
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