E-Mail Security as Cooperation Problem

E-mail communication still has to cope with certain security problems. The most visible result is the mass of unsolicited messages outnumbering the regular e-mails in magnitudes. The technical reasons for this unfavorable situation are manifold, e.g., unreliable sender authentication, loose and ad-hoc coupling between the involved servers, and only few ways to complain about misbehavior of users of foreign systems. In this paper, we will show that resolving these problems requires a deeper analysis of the related economic aspects. We will demonstrate in a simplified game-theoretical model that the individual choices of the involved parties will lead to a suboptimal state, where less effort is put into the security of e-mail communication. As a consequence, some kind of cooperation between the involved parties is needed to implement functions which provide a social benefit rather than an individual one.