Data replicate in SAPCAR on HANA FROM ECC(Retail) without SLT

Hi,

We are going to use SAP CAR on HANA . ECC(IS-retail) system is on HANA1 and SAP CAR is on HANA2. We dint use SLT for data replication from ECC to CAR because both are in HANA. My question is how data will replicate in CAR on HANA from ECC? any connection is required ?

Please update?

Thanks,

abaper