Chapter 16

16.1	We've said that one advantage of BOOTP over RARP is that BOOTP can work through routers, whereas RARP, which is a link-layer broadcast, cannot. Yet in Section 16.5 we had to define special ways for BOOTP to work through a router. What would happen if a capability were added to routers allowing them to forward RARP requests ?
A:	A router could forward an RARP request to some other host on one of the router's other attached networks, but sending a reply then becomes a problem. The router would also have to forward RARP replies. BOOTP doesn't have this reply problem since the address to reply to is a normal IP address that the routers know how to forward anyway. The problem is that RARP uses only link-layer addresses, and routers don't normally know these values for hosts on other, nonattached, networks.
16.2	We said that a BOOTP client must use the transaction ID to match responses with requests, in case there are multiple clients bootstrapping at the same time from a server that broadcasts replies. But in Figure 16.3 the transaction ID is 0, implying that this client ignores the transaction ID. How do you think this client matches the responses with its requests?
A:	It could use its own hardware address, which should be unique, and which is set in the request and returned in the reply.