In Nov 2021, NBN Co announced that starting end of March 2022, they will implement 2 new functions to VDSL2 lines (FTTN and FTTB) on the NBN network, Save Our Showtime (SOS) and Robust Overhead Channel (ROC). These functions are designed to improve the stability of a VDSL2 line by preventing dropouts due to sudden large noise bursts, ensuring reliable connections to the Internet. For CPEs not supporting these new functions, another function, Seamless Rate Adaptation (SRA) will be required to ensure connectivity under certain noisy conditions. Draytek legacy routers/Modems already support dynamic SRA. The new firmware released for them will do the switch automatically when the SOS-ROC feature will be released.


Vigor2766 and Vigor2866 Series

Draytek has released firmware version 4.4.2_MDM2  supporting  SOS/ROC. Use modem code 1271101.

Vigor2866 has now an updated firmware   (V4.4.1-MDM2) that supports  SOS/ROC


Vigor2765 and Vigor2865 Series

For current DrayTek VDSL2 router models, such as the Vigor2765 and Vigor2865 series do support the new NBN’s SOS/ROC functions. While current firmware support the bidirectional dynamic SRA function (which should be sufficient) but if you want the SOS-ROC feature then you will need to execute a telnet command to upgrade to the SOS/ROC function.

The telnet command to enable SOS/ROC is:

vdsl optn sra bi 4

Sys reboot                        ( rem:   to save settings )

A new firmware that enables the SOS/ROC function is available now on our download page – 2765- V4.4.2  and 2865 –  V4.4.0 MDM4

Vigor2862 and Vigor2762 Series

The Vigor2862 and Vigor2762 series routers do not support SOS/ROC functions. However, the latest firmware fully supports bidirectional dynamic SRA. This function is sufficient for the router to maintain a reliable connection to the Internet on an SOS/ROC enabled VDSL2 line.

Vigor130,Vigor132, Vigor2620L Series, Vigor2760 Series , Vigor2860 and Vigor BX2000 Series Routers

You will need to upgrade these routers to the new firmware as it becomes available to ensure a reliable connection to the Internet using an SOS/ROC enabled VDSL2 line.

New firmware for the Vigor2760 and Vigor130-132 is now available for download. This firmware supports bi-directional dynamic SRA allowing the router to have a stable connection on an SOS/ROC enabled VDSL line.

Firmware details


Annex A Model: VDSL2 57c817, ADSL 575a11. Suitable for SOS-ROC VDSL lines of NBN



Annex A modem code VDSL2 579f17, Suitable for SOS-ROC VDSL lines of NBN


This modem is SOS-ROC enabled. Use the latest firmware



Annex A Model -57c817_575a11 -SOS-ROC compatible

Vigor2620L / Vigor2860

New firmware for the Vigor2620L series and Vigor2860 series routers are now available on our website. Please upgrade to the new firmware to ensure reliable connections to the Internet using an SOS/ROC enabled VDSL2 line.

Vigor2620              –  modem code 09

Vigor 2860                   -Modem Vector5

Vigor BX2000  – Modem 6