What traffic does the IAP send to IP 224.0.0.251 on udp port 53535?
A:
The multicast traffic to IP address 224.0.0.251 on udp port 5353 is generally used for MDNS. If we analyze the uplink packet capture of an instant cluster, we may notice the IAP sending traffic to multicast IP 224.0.0.251 on udp port 53535.
When Airgroup is enabled and when there are airgroup-servers present in the "airgroup server table", IAP may send traffic to 224.0.0.251 on udp port 53535 for swarm sync. These are not mDNS traffic packets.
However, when IAP sends MDNS queries and responses to the Airgroup servers and users, it would be sent on udp port 5353 and IP 224.0.0.251.
224.0.0.251 on udp port 5353 = MDNS
224.0.0.251 on udp port 53535 = IAP Swarm Sync
MDNS packets:
IAP Swarm Sync:
