EXFO FTB-8510B Guia Del Usuario página 1318

Glossary
Next-Gen - Virtual Concatenation (VCAT)
assigned number 0, the second one is assigned number 1, and so on
for the remainder of the VCG, up to X-1. So, for a STS-1-21v the
sequence indicator would go from 0 to 20.
In the event that the terminating equipment is unable to recover the
frame or the sequence, or if there is too much differential delay, the
system is equipped to generate alarms (LOA and LOS) to the
management system to highlight these conditions.
Low-Order Virtual Concatenation (LO VCAT)
LO VCAT provides bandwidth for links that require speeds greater than 1.6
Mb/s (VT 1.5/VC-12), but less than 51.84 Mb/s. LO VCATs are designated by
VT-1.5/2/6-nv for SONET and VC-11/12-nv for SDH.
LO VCAT is typically used for sub-rate 10M, sub-rate 100M, and 100 Mb/s
Ethernet data services.
LO VCAT Frame Structure
As described above, low-order paths are used to form VCGs to
transport payloads that do not efficiently fit into HO VCAT STS-1/3c or
SDH VC-3/VC-4 containers. These LO VCAT payloads are defined in the
following table.
A VCG can be created by using the SONET VTn-Xv or the SDH
VC-11/12-Xv, where the value of X can range between 1 and 64 (see
figure SONET VTn-Xv on page 669 and SDH VCn-Xv on page 669).
668
SONET SDH
VT1.5 VC-11
VT2 VC-12
VT3 -
VT6 VC-2
Rate
1600 kb/s 1600 to 102400 kb/s
2176 kb/s 2176 to 139264 kb/s
3328 kb/s 3328 to 212992 kb/s
6784 kb/s 6784 to 434176 kb/s
FTB-8100 Series Transport Blazer
Capacity