Check: CISC-RT-000850
Cisco IOS XE Router RTR STIG:
CISC-RT-000850
(in versions v2 r9 through v1 r1)
Title
The Cisco multicast Rendezvous Point (RP) must be configured to rate limit the number of Protocol Independent Multicast (PIM) Register messages. (Cat II impact)
Discussion
When a new source starts transmitting in a PIM Sparse Mode network, the DR will encapsulate the multicast packets into register messages and forward them to the RP using unicast. This process can be taxing on the CPU for both the DR and the RP if the source is running at a high data rate and there are many new sources starting at the same time. This scenario can potentially occur immediately after a network failover. The rate limit for the number of register messages should be set to a relatively low value based on the known number of multicast sources within the multicast domain.
Check Content
Review the configuration of the RP to verify that it is rate limiting the number of PIM register messages. ip pim rp-address 10.2.2.2 ip pim register-rate-limit nn If the RP is not limiting PIM register messages, this is a finding.
Fix Text
Configure the RP to rate limit the number of multicast register messages. R2(config)#ip pim register-rate-limit nn
Additional Identifiers
Rule ID: SV-216723r855829_rule
Vulnerability ID: V-216723
Group Title: SRG-NET-000362-RTR-000121
Expert Comments
CCIs
Number | Definition |
---|---|
CCI-002385 |
The information system protects against or limits the effects of organization-defined types of denial of service attacks by employing organization-defined security safeguards. |
Controls
Number | Title |
---|---|
SC-5 |
Denial Of Service Protection |