5. A SIPS operator, including of a DNS system with no settlement guarantee, but in which the SIPS participants face credit exposures arising from the SIPS payment, clearing and settlement processes, shall have in place rules or contractual arrangements with these participants. The rules or contractual arrangements shall ensure that the SIPS participants provide sufficient resources, as referred to in paragraph 4, to cover credit exposures resulting from the SIPS payment, clearing and settlement processes in relation to the two participants which, together with their affiliates, have the largest aggregate credit exposure.