[LINK] NBN upgrade

[David]

On 2021-11-20 08:44, Tom Worthington wrote:
>>>
>>> NBN will introduce two new functions to FTTN and FTTB services called Save Our Showtime (SOS) and Robust Overhead Channel (ROC) ...
> 
> What are they?

I'm told these are level-2 enhancements to VDSL2 which try to keep the modem in sync during brief noise bursts.  Otherwise service will be interrupted while both ends go through the laborious process of negotiating the bit-rate in each of the usable bandwidth "bins" available on the copper.

(DSL is a great practical illustration of Claude Shannon's famous theorem IMO.  Some modems can even display a bar-chart of the number of bits negotiated per bin over the total bandwidth.)

DrayTek have released firmware upgrades for some older models which may keep them going even though they don't support SOS/ROC;  the new modem code supports full-duplex service rate adaption (SRA).

> ps: I this why there are boxes of unused NBN devices for sale at the Canberra tip shop?

Perhaps...(:-)

DL