Bandwidths of the various clock types

 The standards documents [4], [5] have defined the acceptable bandwidths for Synchronisation Supply Units and SDH Equipment Clocks. These are

• $B\leq 3$mHz for an SSU
• $1 \leq B\leq 10Hz$ for an SEC

It will be shown in section 6.4 that although no bandwidth has been defined for a primary reference clock, B=0.3mHz would produce noise that lies below the mask.