In the proposed solution, we assume that this routing logic is built into the processing component itself. If we look back at Option A, we remember that we dismissed this approach partly because we had to hard-code some logic into each component. How is the Routing Slip better? The key difference is that the router used in the Routing Slip is generic and does not have to change with changes in the routing logic. The routing logic incorporated into each component is similar to a Return Address (159), where the return address is selected from a list of addresses.
