Re: Upstream bandwidth usage

[Mel Beckman <mel () beckman org>]

I’m not mistaken, it also depends on the optics in the splitter, given that GPON is bidirectional single strand fiber. 

-mel via cell

> On Jun 9, 2022, at 5:01 PM, Raymond Burkholder <ray () oneunified net> wrote:
>
> 
>
> > On 2022-06-09 17:35, Michael Thomas wrote:
> >
> > > On 6/9/22 4:31 PM, Mel Beckman wrote:
> > > Adam,
> > >
> > > Your point on asymmetrical technologies is excellent. But you may not be aware that residential optical fiber is 
> > > also asymmetrical. For example, GPON, the latest ITU specified PON standard, and the most widely deployed, calls 
> > > for a 2.4 Gbps downstream and a 1.25 Gbps upstream optical line rate.
> >
> > Why would they mandate such a thing? That seems like purely an operator decision.
>
> There are also vendor issues involved.  I am glad that Mel mentioned 'optical line' rate.  Which becomes a 
> theoretical thing.  If the line cards aren't set up with buffering properly, then line rate won't be seen.  And I 
> think the line cards can also be easily over-subscribed.  Oh, and due to the two or three step fan-out of 8/16/32, 
> upstream becomes even more limited.
>
> So, if you have FTTH with 1::1 house::port, then you are cooking with fire.  Else, it is the luck of the draw in 
> terms of how conservative the ISP is provisioning a GPON infrastructure.  Which, I suppose, depends if it is 1G or 
> 10G GPON.