EXFO FTB-800 Series for FTB-1 - Manual (Page 445)

Test Functions
NetBlazer 435
OH - SONET/SDH

Z7 /K4 : Extended signal label
Default all OH
Returns all TX overhead bytes to their factory default values.
Bits
Description
Z7 (SONET) K4 (SDH)
1 Extended signal label. Bits 12 to 19 of the 32 bit frame
multiframe (see Z7/K4 Structure on page 433) contain the
extended signal label.
2 Virtual concatenation. Bits 1 to 5 of the 32 bit frame multiframe
(see Z7/K4 Structure on page 433) contain the LO virtual
concatenation frame count while bits 6 to 11 contain the LO
virtual concatenation sequence indicator.
3 - 4 unassigned and reserved for APS signaling for protection at the
lower order path level.
5 - 7 These bits in combination
with bit 8 of V5 are allocated
for RDI -V/ERDI-V signal
Optional use.
8 unassigned and reserved for a lower order path data link.