Question 240
At Dunhaven University, the campus systems team is preparing a multi-building classroom network upgrade. The operational constraint is classroom Wi-Fi and VoIP availability. The owner reports that the correction is complete for this issue: Receivers in another routed subnet cannot join an allowed multicast source despite working unicast routing. Which result BEST demonstrates that this specific issue was resolved?
Explanation
Correct Answer
A cross-subnet test receiver obtains the intended multicast group while unrelated segments remain unaffected. This is the relevant acceptance observation for the reported issue: Receivers in another routed subnet cannot join an allowed multicast source despite working unicast routing. The intended corrective choice is: Use a supported multicast routing design such as PIM with correct rendezvous/source reachability where required. At Dunhaven University, this outcome verifies actual operation under classroom Wi-Fi and VoIP availability, rather than only a ticket marked complete.
Incorrect Answers
Only member ports and required router-facing ports receive the multicast traffic during observation. Such an observation would verify a separate issue: A video VLAN floods all switch ports with a multicast stream although only some hosts joined. It would follow the distinct action: Enable and validate IGMP snooping with correct multicast group membership on the receiver VLAN. Here the reported failure is Receivers in another routed subnet cannot join an allowed multicast source despite working unicast routing. The decisive result for Dunhaven University must instead be: A cross-subnet test receiver obtains the intended multicast group while unrelated segments remain unaffected.
Receiver memberships persist across query intervals and multicast delivery remains stable. Such an observation would verify a separate issue: IGMP membership entries disappear on a standalone VLAN because no device sends periodic membership queries. It would follow the distinct action: Provide a suitable IGMP querier or multicast router for the VLAN under the supported design. Here the reported failure is Receivers in another routed subnet cannot join an allowed multicast source despite working unicast routing. The decisive result for Dunhaven University must instead be: A cross-subnet test receiver obtains the intended multicast group while unrelated segments remain unaffected.
A management test permits authorized SSH and rejects unapproved insecure sessions. Such an observation would verify a separate issue: A switch is managed with shared credentials over insecure legacy protocols. It would follow the distinct action: Configure supported SSH-based management and individual authenticated accounts or AAA, disabling insecure access methods. Here the reported failure is Receivers in another routed subnet cannot join an allowed multicast source despite working unicast routing. The decisive result for Dunhaven University must instead be: A cross-subnet test receiver obtains the intended multicast group while unrelated segments remain unaffected.