The parameter is available only when - CPRI port is set to structure-aware mode and - sa-type = 4 (for VSD raw) This parameter identifies the subchannel number (Ns) in the CPRI control word as the start of a VSD raw group. VSD raw group can be used to define a segment of Ctrl_AxC region or VSD region within the CPRI control word. The defined segment is restricted to consecutive subchannels defined by schan-start and schan-size parameters. - Ns = [4..7] is the valid range of the Ctrl_AxC region within CPRI control word. - Ns = [16 : (p-pointer - 1)] is the valid range of the VSD region within CPRI control word. Since p-pointer is another provision parameter. Valid range of VSD region can only be known after p-pointer is set by user. Prior to p-pointer provision, default valid range for VSD region is restricted to Ns = [16..19] This parameter can be modified only when roe is shutdown. And the modification of this parameter may cause traffic interrupt and need to modify it in both roe mapper and demapper so that the new value can work.