Packet Loss

If you've played online games, you've probably seen your character suddenly snap back to where you were a few seconds ago. To understand why this happens, we need to look at how the internet delivers data.

The internet doesn't send data as a single massive chunk. Just like splitting a big shipment into smaller delivery boxes, it breaks data into tiny pieces and labels each box with an address and sequence number. Each individual box is called a packet.

These boxes don't fly straight to their destination. They pass through several transit warehouses along the way—devices called routers in the networking world. When boxes flood into a warehouse, they're queued on shelves and processed one by one.

But when the shelves are completely full, there's no room left for incoming boxes. The warehouse has no choice but to simply discard them. This failure of some boxes to reach their destination is packet loss. When the packet containing your character's latest position goes missing, the game server snaps you back to the last confirmed location it received.

Fortunately, most internet protocols include an agreement to resend missing boxes. When the receiving end says, "Box #3 never arrived," the sender ships that box again. This is known as retransmission.

Because of this, reading web pages or downloading files won't result in corrupted content even if loss occurs. It just takes extra time to request and resend the missing data, making the page feel slower to load.

The real trouble is data that becomes useless if it arrives late—like your position in a fast-paced game or your voice during a live call. Getting your coordinates from one second ago does no good when you've already moved.

So these real-time connections don't bother waiting for lost boxes; they just skip them and move on. The missing pieces show up on your end as jittery gameplay, sudden rubberbanding, or choppy audio.

Let's return to the warehouse analogy. Dropping boxes is fundamentally different from having a narrow highway. A narrow highway (low bandwidth) means fewer boxes can travel at once, making large downloads take longer. Dropping boxes (packet loss), on the other hand, causes stutters and lag spikes regardless of how small the data is.

That's why upgrading to a faster internet plan might not fix in-game rubberbanding. Overcrowded routers or unstable wireless signals have nothing to do with highway width. Wi-Fi is especially prone to this: walls and radio interference can easily corrupt packets, causing them to be discarded.

In fact, a tiny bit of packet loss isn't a malfunction. The internet was intentionally designed around the assumption that packets will occasionally get dropped. It only becomes a noticeable problem when the loss rate spikes high enough to disrupt your screen.