Which three statements about ASM and SSM are correct? (Choose three.)
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A. B. C. D. E.ACD.
ASM (Any-Source Multicast) and SSM (Source-Specific Multicast) are two multicast distribution modes that can be used with PIM (Protocol Independent Multicast).
Here are the correct statements about ASM and SSM:
A. By default, the SSM group range for PIM is 232.0.0.0/8 and for PIM6 is FF3x/96.
This statement is correct. The SSM group range is a range of IP addresses that can be used to identify multicast groups in SSM mode. The default SSM group range for IPv4 is 232.0.0.0/8, and for IPv6, it is FF3x/96. These ranges are reserved for SSM and are not used in ASM mode.
B. PIM ASM is not fully supported on a vP.
This statement is also correct. vP (Virtual Port-Channel) is a technology that allows multiple physical links to appear as a single logical link to the network layer. PIM ASM is not fully supported on a vP, which means that multicast traffic may not be distributed correctly when using PIM ASM with vP. As a result, it is recommended to use SSM or PIM BiDir (Bidirectional PIM) instead of PIM ASM with vP.
C. In ASM mode, only the last-hop router switches from the shared tree to the SPT.
This statement is true. In ASM mode, multicast traffic is initially sent to the shared tree. However, if a last-hop router receives a multicast packet from a source, it switches the traffic from the shared tree to the SPT (Shortest Path Tree) to optimize the distribution path.
D. ASM mode requires that you configure an RP.
This statement is correct. An RP (Rendezvous Point) is a multicast router that acts as a root for the multicast distribution tree in ASM mode. It is responsible for forwarding multicast traffic from the source to the receivers. In ASM mode, you need to configure an RP for each multicast group, which requires additional configuration and maintenance.
E. If you want to use the default SSM group range, you must configure the SSM group range.
This statement is incorrect. If you do not configure an SSM group range, the default range of 232.0.0.0/8 (for IPv4) or FF3x/96 (for IPv6) will be used automatically. Therefore, there is no need to configure the SSM group range if you want to use the default range.
In conclusion, the correct statements about ASM and SSM are: