The confirmation also specifies a "calculation agent" who is responsible for making determinations as to "successors" and "substitute reference obligations" (for example necessary if the original reference obligation was a loan that is repaid before the expiry of the contract), and for performing various calculation and administrative functions in connection with the transaction. By market convention, in contracts between CDS dealers and end-users, the dealer is generally the calculation agent, and in contracts between CDS dealers, the protection seller is generally the calculation agent.