Nagle's algorithm is a TCP optimization technique that reduces network packet overhead by buffering small outgoing messages, but it can introduce latency when combined with delayed ACK. The article explains the algorithm's mechanics, its problematic interactions with other TCP features, and how to disable it via TCP_NODELAY for latency-sensitive applications.
This article reverse-engineers the UniFi inform protocol (port 8080) and discovers that while the AES-128-CBC encrypted payload requires per-device keys, the first 40 bytes of every packet are unencrypted and contain the device's MAC address at bytes 8-13. This plaintext MAC allows routing of inform traffic without decryption, enabling multi-tenant UniFi controller hosting on shared infrastructure.