WDM

its about the hardware design and signal flow . in UPS we use transponder cards directly receive the traffic from the customer side then convert it fro optical to eectrical form and make payload mapping from SDH / SONET ethernet to O****hen header frame adding and convert it back from electrical to optical through SFPs . unlike the U 64 which uses Tributary , line and cross connection boards which do the same steps

The difference is mainly in the slot capability. U64 is more larger than UPS shelf, UPS shelf can accommodate only 16 service boards, U64 can accommodate 64 service boards. Regarding the way of use the shelf, usually UPS shelf is used for optical as per other OSN models UPS shelf.

This post was last edited by yjhd at 2019-02-01 06:17. The U64 has 64 service board slots. The UPS has only 16 or 18 service board slots. Their role in the network is different. U64 is mainly used for cross-connection of electrical layers. It has high electrical layer service scheduling capability. UPS is mainly used as an optical layer subrack to place boards such as FIU/OAU/WSMD4. so the main difference is U64 is electronic layer subrack, UPS is optical layer subrack.