We will set up traffic between one given site and all other sites connected to the same switch, as shown in Figure 4. In this case, all traffic must go through only one switch. Therefore, there are five possible combinations.
Figure 4: Switch-by-Switch Two-way Full Duplex Configuration
In the current AAI topology (Figure 1), this scenario is only possible for the Chicago switch, since for the California switch it would be equivalent to the Point-to-Point Full Duplex Configuration, and there is only one main site directly connected to the Maryland switch.