Fig. 2

Modeling of a stepping-stone host. This figure contains host h_i with one incoming connection C_i¹ and one outgoing connection C_i²; the incoming connection C_i¹ has one request (send) stream S_i⁽¹⁾ and one response (echo) stream E_i⁽¹⁾, and the outgoing connection C_i² has one request stream S_i⁽²⁾ and one response stream E_i⁽²⁾, where the index i represents the host h_i