618 CHAPTER 36: PIM C ONFIGURATION COMMANDSbe BSR, thus the routers cannot receive or forward BSR messages other thanthese two. Even legal BSRs cannot contest with them.Problems may still exist if a legal BSR is attacked, though these two measures caneffectively guarantee high BSR security.The source parameter in the rule command is translated as BSR address in thebsr-policy command.Related command: acl and rule.Example# Configure BSR filtering policy on routers, only 101.1.1.1/32 can be BSR and allothers are illegal. system-viewSystem View: return to User View with Ctrl+Z.[SW8800] multicast routing-enable[SW8800]pim[3Com-pim] bsr-policy 2000[3Com-pim] quit[SW8800] acl number 2000[3Com-acl-basic-2000] rule 0 permit source 101.1.1.1 0c-bsr Syntaxc-bsr interface-type interface-number hash-mask-len [ priority ]undo c-bsrViewPIM viewParameterinterface-type interface-number:. Interface type and interface number, used tospecify the interface. The candidate BSR is configured on the interface. PIM-SMmust be enabled on the interface first.hash-mask-len: Length of the mask. The value ranges from 0 to 32.priority: Priority of the candidate BSR. The larger the value of the priority, thehigher the priority of the BSR. The value ranges from 0 to 255. By default, thepriority is 0.DescriptionUse the c-bsr command to configure a candidate BSR.Use the undo c-bsr command to remove the candidate BSR configured.By default, no candidate BSR is set.When configure the candidate BSR, the larger bandwidth should be guaranteedsince a great amount of information will be exchanged between BSR and otherdevices in the PIM domain.
