National Australia Bank is winding down its white-label payments processing business Evolution Payments.Brian Walsh, general manager of media at NAB, confirmed the decision. He wrote in an email that white-label merchant acquiring was no longer part of NAB's strategy. Evolution Payments planned to make use of the payments switching technology developed by Distra, an innovator founded in Sydney in 1999 that counts Starfish Ventures as a key investor.NAB invested A$20 million in convertible notes in Distra in late 2008, equal to a one quarter stake in the firm at the time.Shortly afterwards Distra announced a "strategic alliance" with NAB, a reference to the then embryonic Evolution Payments business.The business plan was to sign up non-bank card issuers to a more efficient payments processing platform. NAB at first planned to target customers in Europe as well as Australia.NAB also implemented the Distra switch as a back-up to its long-running legacy switch provided by ACI.Industry talk suggests that NAB has also decided to discontinue use of the Distra back-up switch, though Walsh wrote in an email that "we do have a current and ongoing relationship with Distra."Distra's relationship with NAB still features as the top case study on the front page of the company's website.While Distra's product may prove unsuitable to NAB's business needs, it does have a growing customer list.The "faster payments" service in Britain uses the switch, and, in August, the company announced "its first significant client in the US", though the client is yet to be named.