Packet Loss

What It Means

Packet loss is the percentage of IP packets that fail to reach their destination during transmission, a quality metric that often matters more than raw speed for real-world experience. Every TCP/IP network tolerates some packet loss, lost packets are retransmitted by TCP, making short file downloads relatively immune to low loss rates. However, real-time UDP traffic (video calls, VoIP, online gaming, live streaming) does not retransmit and degrades visibly with even small loss rates: 0 to 0.5% loss is imperceptible, 0.5 to 1% causes occasional stutter, 1 to 2% makes Zoom calls feel choppy and web pages feel sluggish, 2 to 5% causes frequent dropped frames and voice dropouts, and above 5% makes most applications unusable. Common causes of packet loss include DOCSIS upstream noise on cable plants (often from a single faulty drop cable in a neighborhood), Wi-Fi interference from neighboring networks and Bluetooth devices, overloaded ISP peering links during peak hours, and faulty ethernet cables or modem firmware bugs. Unlike speed, you cannot "buy a higher tier" to fix packet loss, it indicates a fundamental network quality problem. The FCC Broadband Nutrition Label does not yet require packet loss disclosure, but the FCC Measuring Broadband America program measures it quarterly across major ISPs. Persistent packet loss on a cable plan (over 1% sustained) is a valid reason to request a truck roll from your ISP, the technician will typically check signal levels at the demarc and may identify a faulty tap or drop cable.

Frequently Asked Questions