The first message ever sent across the network that became the internet was not “Hello, world.” It was not a grand declaration. It was two letters, transmitted by accident, before the system fell over: LO.
That two-letter packet is the ancestor of every connected device, every IoT sensor, and every web request running today. The story of how it happened is also a surprisingly useful lesson for anyone building embedded systems and connected hardware right now.
What actually happened on October 29, 1969
On the evening of October 29, 1969, a programmer named Charley Kline sat at a terminal in Leonard Kleinrock’s lab at UCLA. His job was simple on paper: log in to a remote computer at the Stanford Research Institute (SRI), roughly 350 miles away, over a brand-new experimental network called ARPANET.
The plan was to type the command LOGIN. The remote machine at SRI was set up to auto-complete the rest once it saw the first few characters, so Kline only needed to start typing. He had a colleague on the phone at the Stanford end to confirm each letter arrived.
He typed L. Stanford confirmed: “Got the L.”
He typed O. Stanford confirmed: “Got the O.”
He typed G – and the SRI system crashed.
So the first message ever transmitted over ARPANET was “LO.” As Kleinrock later liked to point out, it was an accidental but fitting first word: “LO” as in “lo and behold.” About an hour later they fixed the bug and completed the full login, but the historic first packet had already gone out, two letters at a time.
Why a crash is the perfect origin story
It is tempting to read this as a cute footnote. It is more than that. The very first thing the internet ever did was fail partway through a transaction – and the system was built well enough that the humans on both ends knew exactly how far it had gotten before it died.
That is the entire discipline of networked systems in miniature. Connections drop. Remote machines crash mid-request. Packets arrive out of order, or not at all. The networks we build on top of ARPANET’s descendants did not eliminate those failures; they learned to expect them and recover gracefully.
If you have ever written firmware for a connected device, you already know this in your bones. The happy path – where the Wi-Fi is solid, the broker is up, and every message is acknowledged – is the easy 20 percent. The real work is the other 80 percent: timeouts, retries, exponential backoff, and idempotent operations that can survive a “LO” moment without corrupting state.
What this means for IoT builders today
Every robust connected product is, in a sense, a long answer to the question raised in 1969: what do you do when the message only half arrives?
A few principles carry straight through from that first crashed session to a modern IoT and embedded build:
- Design for the dropped connection, not the perfect one. Assume your ESP32 will lose Wi-Fi mid-publish. Buffer locally, confirm delivery, and make re-sends safe to repeat.
- Make failures observable. The 1969 team succeeded partly because they could see “Got the L, got the O.” Good telemetry and logging on a deployed device is the modern equivalent – you cannot fix what you cannot see.
- Acknowledge, then act. Protocols like MQTT exist precisely because fire-and-forget is not good enough for devices in the field. Quality-of-service levels are just a formalized version of “tell me you got the O.”
The Philippine angle
For teams building IoT here in the Philippines – whether it is an agricultural sensor network in the provinces or a thesis prototype in a Metro Manila university lab – this reliability-first mindset matters even more. Connectivity is rarely flawless. Cellular and Wi-Fi coverage varies, power can be intermittent, and devices often sit far from anyone who can press a reset button.
A connected product that assumes a perfect link will work beautifully on the bench and fail in the field. One that is designed around the “LO” reality – expecting the half-finished transaction and recovering from it – is the one that survives real deployment.
That gap between “works in the lab” and “works in the world” is exactly where we spend our time. If you are turning a connected-hardware idea into something that has to run unattended, let’s talk about your build. The internet started with a crash. Your product does not have to.
