This is Business::OnlinePayment::TCLink, a Business::OnlinePayment backend module for the TrustCommerce payment gateway. It is only useful if you have an account with TrustCommerce: http://www.trustcommerce.com/ . Business::OnlinePayment is a generic interface for processing payments through online credit card processors, online check acceptance houses, etc. (If you like buzzwords, call it an "multiplatform ecommerce-enabling middleware solution").