what is the types of osn 9800 subracks and diffrences ?

There are 3 types of OSN9800 subracks, which are:
1. U16/U32/U64, these 3 models are used for electric layer, have centralize cross-connection boards, works with service boards like tributary boards and line boards for OTN service, or boards for SDH/packet services. The cross-connection capacity for each slot of these subracks are 400Gbps OTN service, or 2000Gbps packet service, or 80Gbps SDH service. The difference between them is that they each have 16/32/64 slots for service boards.
2. M24, this is newly introduced subrack. M24 boards is used for electric layer, and has centralize cross-connection boards, too. M24 subrack have 12 big slots, each of them can be used as 2 small slots. The cross-connection capacity for each small slots are 100Gbps OTN service, 40Gbps VC-4 service, and all slots on the whole subrack share 80Gbps VC-3/VC-12 cross-connection capacity.
3. UPS subrack, this subrack is used for optical layer boards, like the muxer/demuxer, amplifiers, also for Transponder boards. In some area, there is also a similar subrack called P18, the difference is this subrack is wider, and have 18 slots for service boards on a DC powered subrack, while the UPS only have 16 slots for service boards on a DC powered subrack.