od, I don't consider RIP to be simple goodness. RIP broadcasts all the routes it knows about every 30 seconds, regardless of the sta- tuses of any other routers in the network. Because it uses broadcasts, every host on the network listens to the updates, even though few can process them. On larger net- works, the updates can be quite large, and consume a lot of bandwidth on expensive WAN links. Another issue with RIP is the fact that it does not use triggered updates. A triggered update is one that is sent when the network changes; nontriggered (timed) updates are sent on a regular schedule. This, coupled with the fact that updates are only sent every 30 seconds, causes RIP networks to converge very slowly. Slow convergence Chapter 10: Routing Protocols is not acceptable in most modern networks, which require failover and conver- gence in seconds. A RIP network with only five routers may take two minutes or more to converge. RIP is a classful protocol, which means that subnet masks are not advertised. This is also an unacceptable limitation in most networks. Figure 10-9 illustrates one of the most common mistakes made when using classful protocols such as RIP. Router A is advertising its directly connected network 10.10.10.0/24, but because RIP is classful it advertises the network without the subnet mask. Without a subnet mask, the receiving router must assume that the entire network is included in the advertise- ment. Consequently, upon receiving the advertisement for 10.0.0.0 from Router A, Router B inserts the entire 10.0.0.0/8 network into its routing table. Router C has a different 10 network attached: 10.20.20.0/24. Again, RIP advertises the 10.0.0.0 net- work from Router C without a subnet mask. Router B has now received another advertisement for 10.0.0.0/8. The network is the same, the protocol is the same, and the hop count is the same. When a newer update is received for a route that has already been inserted into the routing table, the newer update is considered to be more reliable, and is itself inse