Save our Showtime (SOS) provides the receiver with a means to rapidly perform a bit loading reduction in a specified part of the frequency spectrum. This can be used in case of sudden noise increases. The SOS Profile provides the parameters to configure the optional procedure for on-line reconfiguration of the Physical Media Dependent (PMD) sub-layer in VDSL2 operation mode. If the SOS procedure is not utilized the relevant profile pointer within the xDSL Line Configuration Vector instance MUST be set to a null value (0). A default profile with an index of '1' will always exist and its parameters will be set to vendor-specific values, unless otherwise specified in this document. The index of this entry is hwVOPSosConfProfIndex.