Re: symmetric vs. asymmetric [was: Verizon Policy Statement on Net Neutrality]

[Jack Bates <jbates () paradoxnetworks net>]

Even so, what makes the channel assignments static? If the downstream 
bands are sitting idle, why can't they be reallocated for use by modems 
needing to send more? Or, presuming upstream isolation between modems, 
why can't multiple channels be dynamically allocated to a modem when 
there is availability and need?

I'm not arguing how it is. Just saying. Why can't we do more? GMPLS 
shows we can get really annoying in our ability to automate in dynamic 
provisioning. I'd think fixing something like DOCSIS would be a cakewalk 
in comparison.

Sorry, I'm just a network guy that plays with routers and servers. I 
expect more out of the geniuses that make stuff for me to play with.

Jack

On 2/27/2015 4:05 PM, Scott Helms wrote:
> Stephen is dead on here.  In DOCSIS the downstream communication happens in
> one or more normal cable TV channel band, ie 6MHz channels from 54 MHz to
> 890MHz.  The upstreams will be (in most cases) either 1.6 MHz, 3.2 MHz, or
> 6.4MHz wide and in the 5-42 MHz range.
>
>
> Scott Helms
> Vice President of Technology
> ZCorum
> (678) 507-5000
> --------------------------------
> http://twitter.com/kscotthelms
> --------------------------------
>
> On Fri, Feb 27, 2015 at 4:56 PM, Stephen Satchell <list () satchell net> wrote:
>
> > On 02/27/2015 01:27 PM, Jack Bates wrote:
> > > My 2 cents. I don't design these things, but you'd think people would
> > > start realizing that static allocation is kind of limiting. Giving
> > > someone 50mb/s with 20mb/s waste is annoying when they are saturating
> > > 3mb/s the opposite direction. Wouldn't it be cool if your backup at
> > > night could use 50mb/s upstream and drop your downstream to 5mb/s
> > > because you aren't downloading anything?
> > That's possible with multicarrier technology, such as xDSL.  When you
> > get into the data-over-cable technology, you find a completely different
> > story -- it's a system limitation that you have an upstream channel that
> > is less efficient than the downstream channel because the upstream
> > channel has to be accessed by a number of sources, with access control,
> > whereas the downstream channel is nothing more than a broadcast pipe
> > (just like 10base-2 Ethernet) where you pick your packets out of the
> > stream.
> >
> > Other technologies have their quirks, too...