let your businessman contact the bank, bank will give you some terminal IDs that you can put on the workstation/server processing the tranx. bank will also provide you a component to comnunication. they also give you a ip address/port number of the bank host. they will aso give the info about the credit card channel data format so that you can write your wrap code and how to keep a transaction. hopely with all these stuff you are the start point. i did that for cibc before.