Dynamic routing is a complex subject. Many protocols exist to exchange
routes between IP hosts. Many of these protocols involve some notion of
security (specifying which machines are allowed to tell a host new
routes). This is not the case with routed. It uses a fairly simple
protocol in which every host is allowed to tell every other host about the
routes it knows. Using a simple metric scheme, one is able to locate the
best (or the real) route to a given network. This is what RIP gives
routed implements the RIP protocol.
You have three controllable options:
routedwon't have anything to say anyway. If you have more than one interface, but don't want to be known as a router, then this option is also for you.