A worldwide network of bulletin board systems — built by hobbyists, run on phone lines, and operating years before the public web existed. At its peak, FidoNet connected over 40,000 nodes across 6 continents.
In 1984, a software developer named Tom Jennings wrote a bulletin board system program called Fido. Almost as an afterthought, he added code that let two Fido systems automatically call each other over ordinary telephone lines to exchange messages while the phone rates were cheapest — usually in the middle of the night. Within months, other sysops (system operators) had connected their BBSs to his. Within years, this informal network had grown to span the globe. That network was FidoNet.
FidoNet operated entirely through store-and-forward messaging: messages were composed offline, bundled into packets, and transferred node-to-node like a digital postal system — each node passing mail along until it reached its destination. There was no central server, no corporate owner, no monthly fee. Just thousands of ordinary people running computers in their homes and offices, connected by modems and phone lines.
"The idea was basically: here's this address system, here's this packet format, and anybody who wants to implement it can. And people did."
— Tom Jennings, FidoNet creatorA hierarchical peer-to-peer network of bulletin board systems exchanging email (Netmail) and public discussion groups (Echomail) via dial-up modem connections, coordinated by volunteer administrators.
Ordinary hobbyists called sysops (system operators), each running a BBS on a personal computer in their home or office — often on a second phone line. No salary, no company backing.
Nodes called each other (or their regional hub) once or twice per day — often at 2–3 AM for cheap phone rates — to exchange bundled message packets. Mail could take 24–72 hours to traverse the globe.
By the early 1990s FidoNet had over 40,000 active nodes, processing millions of messages per day across 6 geographically-defined zones. It was the largest non-commercial network in the world.
Tom Jennings wrote the original Fido BBS software in late 1983 and early 1984, running it on a PC-compatible in San Francisco. He connected with another Fido sysop in Baltimore, and from those first two nodes, everything grew. Jennings later donated the FidoNet technology to the public domain, ensuring it could never be commercialized.
He later became known for his work in hardware hacking, zines, and queer activism — FidoNet was just one chapter of a colorful career.
FidoNet used a store-and-forward architecture: messages were written offline, bundled into compressed archive files called packets, and physically transferred from computer to computer via modem dial-up. Each node stored incoming mail and forwarded it toward its destination — like a relay race, but for data, running on ordinary phone lines.
FidoNet four-level hierarchy: Zone → Region → Net → Node → Point (optional)
Every day between 02:00 and 03:00 local time (the "Zone Mail Hour"), all FidoNet nodes were expected to stop accepting user calls and remain available for mail transfer from other nodes. During ZMH, your node's mailer software would call other nodes to exchange queued packets, then accept incoming calls from nodes that needed to deliver mail to you. Outside ZMH, nodes could call each other any time they had mail to send (called "crash mail").
Every FidoNet node ran mailer software — programs responsible for dialing out, answering incoming calls, negotiating the FTN handshake protocol, and transferring packet files. Popular mailers included BinkleyTerm, FrontDoor, InterMail, and the classic SEAdog. The mailer sat in front of the BBS software, answering the phone first, identifying FidoNet calls (via a "EMSI" or "FTSC-0001" handshake), handling the transfer, then passing the call to the BBS for regular users.
Mail was packed into .PKT files following a standardized format (FTSC-0001 Type 2+).
Individual messages had headers containing source address, destination address, date, subject, and flags.
Multiple messages were bundled together, then compressed into .TIC or .ARC archives
for transfer. The whole bundle might be a few kilobytes for an evening's mail exchange.
Every Friday, a master nodelist was published and distributed throughout the network — a plain-text file listing every known FidoNet node, its address, phone number, modem speed, flags, and sysop name. Nodes downloaded the new nodelist from their uplink hub. Without it, your mailer couldn't look up how to reach anyone. At its peak the weekly nodelist was over 1 MB — enormous for 1993 — and had to be distributed across the entire network within 48 hours.
Every FidoNet node had a unique address in the format Zone:Net/Node.Point. This was the routing key for all private Netmail — the equivalent of an email address, years before @-sign email existed on public networks.
Continental region. Zone 1 = North America, 2 = Europe, 3 = Oceania, 4 = Latin America, 5 = Africa, 6 = Asia.
A local network of nodes, usually covering a city or region. Each Net had a host node (Net/0) that acted as a routing hub.
An individual BBS. Node 0 is the Net host. Nodes had their own phone line and answered incoming calls.
Optional "leaf" connection — a home user who picks up mail from their boss node but doesn't answer calls. Points could read and write mail without running a 24/7 BBS.
Point-to-point private messages — like email. Addressed to a specific Zone:Net/Node. Routed through the hierarchy. Could carry binary file attachments. Analogous to SMTP email.
Public conference messages propagated to every subscribed node — like Usenet newsgroups. An "echo" (conference) had a name like FIDONEWS or DOVE-NET. A message posted anywhere appeared everywhere within 1–3 days.
Automatic file distribution — binary files (shareware, door games, nodelist updates) propagated through the network the same way Echomail worked, using .TIC (Tick) file description files alongside the binary.
Nodes could subscribe/unsubscribe to echoes by sending a Netmail to the AREAFIX address on their uplink. The remote system would automatically add or remove the echo from the node's feed.
FidoNet was never just a technology — it was a culture. In an era before the web, BBSs were where curious, technically-inclined people found their tribe. You dialed in after school or late at night, paying long-distance rates if you had to, just to read the latest posts in your favorite echo conference and leave a reply that might reach someone in Germany or Japan within the week.
Every week, the FidoNews — a plaintext electronic newsletter — was distributed across the entire FidoNet via FileEcho. It contained technical announcements, policy discussions, humor, letters, node statistics, and op-ed pieces written by sysops. FidoNews was the town square of the FidoNet community, and reading it was how you stayed connected to the global network's happenings. Issues are archived and still readable today.
Dozens of BBS software packages existed, most of them implementing FidoNet compatibility. Choosing your BBS software was a serious decision — some were commercial products, others were freeware, and each had different file transfer protocols, door game interfaces, and configuration complexity.
One of the beloved features of BBSs was door games — external programs that users could run through the BBS. The BBS would "drop to" the door program, passing the user's connection through a serial "drop file," then resume when the game exited. Legendary door games included Trade Wars 2002 (space trading), Legend of the Red Dragon (RPG), Usurper (dungeon crawler), and Barren Realms Elite (strategy). High scores persisted between sessions, and many had inter-BBS competitive modes via FidoNet.
FidoNet was not just a historical curiosity — it was a proof of concept that a global, decentralized communications network could be built and run entirely by volunteers, without corporate ownership, without central servers, and without charging users anything. It anticipated concepts that the internet would later formalize, and many of its architects went on to shape the early commercial internet.
FidoNet's Netmail (1984) is functionally identical to SMTP email — addressed messages relayed hop-by-hop through a hierarchy of servers — but ran on phone lines instead of TCP/IP.
Echomail (1987) predates the public web's discussion boards and is directly comparable to Usenet, with subscribe/propagate semantics and threaded replies.
FileEcho propagated shareware, games, and utilities across the global BBS network automatically — a content distribution network run by volunteers years before Napster or BitTorrent.
FidoNet's FSP (FidoNet Standards Proposals) process was a direct precursor to the IETF RFC process. Technical standards decided by rough consensus among implementers.
As early as 1989, gateways existed between FidoNet Echomail and Usenet newsgroups — bridging the two largest pre-web networks. Some users never knew which network they were "really" on.
FidoNet Points (1988–89) let home users receive mail through a boss node without running 24/7 — the same model as dial-up ISP email accounts, a full decade earlier.
"FidoNet was essentially email, mailing lists, newsgroups, and file sharing — all running without the internet, without servers, without anyone being in charge. It worked because people wanted it to work."
— Description of FidoNet's functional equivalence to internet servicesFidoNet is still alive. As of 2024, the network publishes a weekly nodelist with roughly 2,000–3,000 active nodes, most connecting via Binkp over TCP/IP rather than modem dial-up. Active Echomail conferences include retro computing discussion, programming, and nostalgia groups. The Synchronet BBS software has a built-in FidoNet mailer, and new BBSs come online every year.
For anyone who wants to experience it: you can Telnet to many active BBSs today
(try bbs.synchro.net on port 23), join Echomail conferences, and exchange
Netmail with sysops around the world — the same way people did in 1991, just over
the internet instead of a phone line.
The governing document of FidoNet. Famous for its pragmatic philosophy: "Sysops can do whatever they want as long as they don't screw up the mail." Still the foundation of FidoNet governance.
The body that maintains FidoNet technical standards. All protocol specifications — packet formats, mailer handshakes, nodelist formats — are documented in freely available FSP documents.
Jason Scott's multi-hour documentary on the BBS era covers FidoNet extensively. Includes interviews with Tom Jennings and dozens of sysops. Freely available online.