In Bootstrap Protocol, how does a client know if a hardware broadcast is intended for another BOOTP client on the same physical net?

When a bootp 开发者_高级运维client receives a reply via hardware broadcast, how does it know whether the reply is intended for another BOOTP client on the same physical net?

the Bootstrap Protocol (defined here) says:

The client should discard incoming packets that: are not IP/UDPs addressed to the boot port; are not BOOTREPLYs; do not match my IP address (if I know it) or my hardware address; do not match my transaction id. Otherwise we have received a successful reply. 'yiaddr' will contain my IP address, if I didnt know it before.

(the transaction ID discussed above is a field in the BOOTREQUEST packet which is assigned a number known by the sender of the request. the field is assigned a random number and it is assumed that there are almost no chance of collision)