Before revision:  We have presented approximate expressions for various cases using Gateaux derivative which allow straightforward numerical analysis. Numerical examples for CCS (cross currency swap)and IRS(interest rate swap) with asymmetric collateralization were also provided. They clearly show the practical relevance of sophisticated collateral management for financial firms. The valuation and the associated issue of collateral cost under the one-way CSA (or unilateral collateralization) , which is common when SSA (sovereign, supranational and agency) entities are involved, have been also studied .
After revision:  We have presented approximate expressions for various cases using Gateaux derivative .