i have 3 sites connecting together with SDH 15454 site A-B with STM-1 and from site B-C STM-16,i want to Aggregated hand-off E1's from Site A-C so site B will be trasparet site for this link.
to be source of link on site A and Drop on site C.
any help to achive this.
there is already cricte between site B-C.
You will need to verify that the cross-connect card in the ONS 15454 (sites B & C) have VC-12 grooming capabilities (XC-VXL and CX-VXC will support VC-12 grooming).
The ONS is designed to groom lower rate signals to higher rate speed lines. Thus, you should be able to aggregate the E1s from the ISPs STM1 with the E1s from Site B and drop them at Site C.
You will need to add an STM1 card(s) to Site B. Your ISP will need to provide the mapping structure of the STM1, so you can understand where the VC-12s, which contain the E1s, are located in the payload. You will then create circuits to map each E1 (the incoming VC-12s within VC3/VC4) from you ISPs STM1 at Site B, to the appropriate VC-12 on the outgoing STM16 line heading toward Site C. At Site C, you will need to map the VC-12s on the STM16 line to the appropriate port on an E1 line card.
I hope this helps. Otherwise, you will need to have someone locally assist you in the explanation.