Charley Kline typed two letters of LOGIN before the far end crashed. Everything you send today travels down a branch of that moment. Follow eight strands, from the telegraph to 800 Gb Ethernet, and see where they cross, merge and get pruned.
Telegraph, telephone and light. The physical layer exists a century before the computer.
24 May 1844 · Samuel Morse, Alfred Vail · Morse code
A 60 km line from Washington to Baltimore carries the first long-distance message in Morse code, the first widely used digital encoding: on, off and timing.
Cooke and Wheatstone already had a working railway telegraph in England from 1838. Relay offices that received and re-sent traffic along long lines were doing store-and-forward switching, the same idea every packet switch uses.
5 Aug 1858 · Cyrus Field, Wildman Whitehouse, William Thomson · Submarine cable
A cable on the Atlantic seabed links Ireland and Newfoundland, cutting message time between Europe and America from about ten days by ship to hours.
Queen Victoria's 98-word greeting took around 16 hours to get through. The cable failed within a month after Whitehouse drove it with about 2,000 volts. A durable cable followed in 1866, and modern fibre still lands at many of the same coasts.
14 Feb 1876 · Alexander Graham Bell, Elisha Gray · Circuit switching
Voice becomes an electrical signal. The telephone network that grew from it, built on dedicated circuits, is the system the internet's designers set out to do differently.
Bell's lawyer filed his patent application on the same day Elisha Gray filed a notice for a similar device. Which arrived first that morning shaped a century of telecoms and years of lawsuits.
3 Jun 1880 · Alexander Graham Bell, Charles Sumner Tainter · Optical comms
Bell sends speech about 200 metres on reflected sunlight. It is the first optical communication system and the ancestor of every fibre link.
Bell considered it his greatest invention, more important than the telephone. It failed in practice because cloud, fog and rain broke the beam. Light needed a protected path, and that took another 90 years.
Transistors, bits, lasers and the idea of a packet. The pieces are invented separately.
1 Jan 1925 · AT&T and Western Electric · R&D
AT&T's research lab produces an outsized share of networking's foundations: the transistor, information theory, early laser theory, Unix and C.
Work done at Bell Labs has earned multiple Nobel prizes. Its long-term funding came from the AT&T monopoly, and the 1984 break-up of the Bell System eventually ended that model of research.
Dec 1947 · John Bardeen, Walter Brattain, William Shockley · Solid-state switch
A solid-state switch replaces the vacuum tube. Every router ASIC, network card and optical transceiver is built from billions of them.
Shockley, angry at being left off the first patent, worked alone over the holidays and designed the junction transistor. The company he later founded in California drew the engineers who left to start Fairchild, and with it Silicon Valley.
Jul 1948 · Claude Shannon · Information theory
Shannon defines the bit and proves every channel has a maximum error-free data rate. Modulation from DSL to Wi-Fi 7 is engineered against the Shannon limit.
The word ‘bit’ came from his colleague John Tukey. Shannon also juggled, rode a unicycle along Bell Labs corridors and built a mechanical mouse that could learn its way through a maze.
7 Feb 1958 · President Eisenhower, Neil McElroy · US Department of Defense
Four months after Sputnik, the US creates the Advanced Research Projects Agency to fund high-risk research. It will pay for the ARPANET.
ARPA's computing office was set up in 1962 under J.C.R. Licklider. Its habit of giving clever people money and freedom is why universities, not a telephone company, built the early network.
16 May 1960 · Theodore Maiman, Hughes Research Labs · Light source
A ruby crystal produces coherent light. Semiconductor lasers followed in 1962 and became the light source inside every fibre transceiver.
The laser was famously called a solution looking for a problem. Physical Review Letters turned down Maiman's paper, so he published a short note in Nature instead.
1961–1965 · Leonard Kleinrock, Paul Baran, Donald Davies · Store and forward
Break messages into small blocks, route each independently, reassemble at the far end. Baran at RAND and Davies at the UK's National Physical Laboratory reach the idea separately; Kleinrock supplies the queueing theory.
Baran wanted a network that could survive a nuclear attack, and AT&T told him it would never work. Davies wanted efficient time-sharing and chose the word ‘packet’ because it translated easily. NPL ran its own packet network from 1969.
Apr 1963 · J.C.R. Licklider · Vision
Licklider describes a network where any computer can use programs and data held on any other. It is the clearest early vision of the internet.
The memo was addressed, half in jest, to the ‘Members and Affiliates of the Intergalactic Computer Network’. Licklider hired or inspired the people, including Bob Taylor and Larry Roberts, who went on to build ARPANET.
17 Jun 1963 · Bob Bemer and the X3.2 committee · ASA X3.4-1963
A 7-bit code for 128 characters. It became the alphabet of email headers, HTTP, DNS names and router command lines, and UTF-8 still begins with it.
The first version had no lowercase letters. Bemer also championed the escape character, ESC, which is why terminals can draw colour.
Jul 1966 · Charles Kao, George Hockham (STL, Harlow) · Target: <20 dB/km
At Standard Telecommunication Laboratories in Essex, Kao and Hockham show that impurities, not glass itself, cause the loss. Purify it below 20 dB/km and fibre beats copper.
Most of the industry thought the target was impossible, so Kao toured glassworks around the world making the case. He received the Nobel Prize in Physics in 2009.
Four nodes become an internetwork. Ethernet, TCP and public-key crypto all appear within a decade.
7 Apr 1969 · Steve Crocker · RFC 1 · Host Software
The first Request for Comments describes host software for the coming ARPANET. The series now runs past 9,000 documents and still defines how the internet works.
Crocker wrote it at night in the bathroom of a shared house so he would not wake anyone. The modest name was chosen so nobody would think graduate students were trying to take charge.
29 Oct 1969 · Leonard Kleinrock, Charley Kline, Bill Duvall; BBN · IMP · Honeywell DDP-516
UCLA connects to SRI through Interface Message Processors built by BBN. By December there are four nodes: UCLA, SRI, UC Santa Barbara and the University of Utah.
Kline typed L and O of LOGIN while on the phone to Duvall at SRI. The system crashed on G. About an hour later the full login went through.
Aug 1969 · Ken Thompson, Dennis Ritchie · PDP-7
A small, portable operating system from Bell Labs. Its descendants, BSD and Linux, carry most of the world's TCP/IP traffic and sit underneath many network operating systems.
Thompson wrote the first version on a cast-off PDP-7, partly so he could keep playing his Space Travel game. Bell Labs had just pulled out of the costly Multics project.
Sep 1970 · Robert Maurer, Donald Keck, Peter Schultz · Under 20 dB/km
Corning's team draws fused-silica fibre that beats Kao's target. Practical optical networking starts here.
Keck recorded the result in his lab notebook with a single word: ‘Whoopee!’
Jun 1971 · Norman Abramson, University of Hawaii · Random access radio
Radio links connect terminals across the Hawaiian islands. Stations transmit when they like and retry after collisions, the idea that became Ethernet's CSMA/CD and Wi-Fi's CSMA/CA.
Abramson chose Hawaii partly for the surfing. Bob Metcalfe later spent time there studying ALOHAnet before designing Ethernet.
Late 1971 · Ray Tomlinson, BBN · SNDMSG + CPYNET
Tomlinson combines a local mail program with a file-transfer tool so messages can cross ARPANET between hosts. user@host addressing is born.
He picked @ because it never appeared in names and read naturally as ‘at’. He said the first message was forgettable, probably something like QWERTYUIOP.
1972 · Dennis Ritchie · C
In 1973 Unix is rewritten in C, making an operating system portable to new hardware. Most network stacks, firmware and routing daemons are still written in C.
C grew out of Ken Thompson's B, itself a cut-down version of BCPL from Cambridge. The famous ‘hello, world’ example comes from Brian Kernighan's tutorials.
22 May 1973 · Bob Metcalfe, David Boggs, Xerox PARC · 2.94 Mbit/s coax
Metcalfe's memo describes a shared coaxial cable where stations listen before talking and back off after collisions. The first version ran at 2.94 Mbit/s between Alto workstations and laser printers.
He named it after the ‘luminiferous ether’ that 19th-century physicists believed carried light. Physics abandoned the ether; networking kept the name.
May 1974 · Vint Cerf, Bob Kahn · TCP · RFC 675
Cerf and Kahn describe gateways that join unlike networks, with a host protocol that makes them behave as one. RFC 675, in December 1974, shortens ‘internetworking’ to ‘internet’.
Kahn was juggling three incompatible networks: ARPANET, packet radio and satellite. Their answer kept the network simple and put reliability in the end hosts, the end-to-end principle that still shapes the internet.
Nov 1976 · Whitfield Diffie, Martin Hellman, Ralph Merkle · Diffie–Hellman
Two strangers can agree a secret key over a channel an eavesdropper is watching. Every TLS, SSH and IPsec session starts with a descendant of this exchange.
At GCHQ in Cheltenham, James Ellis, Clifford Cocks and Malcolm Williamson had found the same ideas between 1970 and 1974. Their work stayed classified until 1997.
Apr 1977 · Ron Rivest, Adi Shamir, Leonard Adleman · Signatures & encryption
A practical public-key system for both encryption and digital signatures. It underpins certificates, the browser padlock and code signing.
Rivest worked out the scheme overnight after a Passover evening at a student's home, and had a draft by morning.
22 Apr 1977 · GTE (Long Beach); Post Office Research (Martlesham Heath) · Field deployment
GTE in California puts fibre into service with real calls, and the British Post Office runs field trials near Ipswich the same year. Within a decade long-distance trunks are going optical.
The research centre at Martlesham Heath, later BT's, became one of the main European centres for optical networking.
22 Nov 1977 · SRI International, BBN, UCL · PRNET · ARPANET · SATNET
Packets leave a van on a California freeway by radio, cross ARPANET, hop by satellite to Norway and London, and come back. It is the first true internetwork demonstration.
The van was a converted bread delivery truck packed with radios. Peter Kirstein's group at University College London handled the British end; they had connected the UK to ARPANET in 1973.
1978 · Jon Postel, Danny Cohen, Vint Cerf · TCP/IP v4 · UDP
Routing and reliable delivery are separated. IP moves datagrams hop by hop; TCP handles ordering and retransmission at the ends. UDP appears for traffic that cannot wait.
Postel argued that voice and other real-time traffic would not tolerate TCP's retransmissions. Version 4 is the first to stick; earlier numbers were drafts.
Feb 1980 · DEC, Intel, Xerox; IEEE · IEEE 802 · 10 Mbit/s
DEC, Intel and Xerox publish 10 Mbit/s Ethernet as an open specification. The IEEE 802 committee forms to standardise LANs, and Ethernet becomes 802.3 in 1983.
The usual explanation for ‘802’ is the committee's first meeting in February 1980. Metcalfe's 3Com, founded in 1979, sold the adapters that put Ethernet into PCs.
Sep 1981 · Jon Postel (editor) · IPv4 · TCP
The definitive IPv4 and TCP specifications. 32-bit addresses allow about 4.3 billion hosts, which seemed absurdly generous at the time.
Postel's robustness principle comes from this era: be conservative in what you send and liberal in what you accept. The IETF still debates its long-term costs.
TCP/IP becomes mandatory, DNS replaces a single hosts file, and companies form to sell routers.
1 Jan 1983 · DARPA, Defense Communications Agency · NCP → TCP/IP
Every host must speak TCP/IP or lose access. Many people count this as the birthday of the internet.
The cut-over was messier than the date suggests and took months to finish. Engineers who lived through it wore ‘I survived the TCP/IP transition’ badges.
Aug 1983 · Bill Joy, UC Berkeley CSRG · socket() · bind() · connect()
Berkeley Unix ships TCP/IP with the sockets programming interface. Because the code was free, universities and vendors adopted TCP/IP instead of writing their own.
DARPA had funded BBN to write the reference stack, but Joy wrote his own and the two camps argued over whose was better. Sockets are still how nearly every networked program opens a connection.
1983 · Novell · IPX/SPX
NetWare file and print servers dominate office LANs through the late 1980s and early 1990s, running Novell's own IPX/SPX protocols.
IPX built each node's address from a network number plus its MAC address, so nobody had to assign addresses by hand. TCP/IP in Windows and the rise of the internet left it stranded.
Nov 1983 · Paul Mockapetris, Jon Postel · RFC 882/883 · UDP/53
A distributed, hierarchical database replaces HOSTS.TXT, a single file of every host name that sites downloaded from SRI.
By 1983 the hosts file was changing faster than it could be copied around. DNS now serves hundreds of millions of domain names on the same basic design.
1984 · ISO, CCITT; Hubert Zimmermann · ISO 7498
A seven-layer model and a full protocol suite meant to become the world's network. Governments mandated it, but TCP/IP won on running code.
The model outlived the protocols. Every network engineer still says ‘layer 2’ and ‘layer 3’, and IS-IS, the OSI routing protocol, runs in many of the largest ISP backbones.
10 Dec 1984 · Len Bosack, Sandy Lerner; software by Bill Yeager · Multiprotocol router
Two Stanford staff members commercialise a router that joins networks running different protocols. Cisco becomes the default supplier of internet routing.
The popular story says they built it to email each other between buildings; the fuller one is that Stanford's networks needed joining. The name comes from San Francisco, hence the Golden Gate Bridge logo.
1985 · David L. Mills · RFC 958 · UDP/123
Computers agree on the time across a network to within milliseconds. Logs, certificates, Kerberos and distributed databases all depend on it.
Mills led NTP development from the University of Delaware for decades. Stratum numbers describe how many hops a clock is from an atomic reference.
15 Mar 1985 · Symbolics Inc. · symbolics.com
A computer maker registers the first commercial domain name. Only a handful more were registered that year.
Symbolics.com is still online as a small history site. There are now well over 150 million .com names.
1985 · IBM · IEEE 802.5 · 4/16 Mbit/s
IBM's LAN passes a token around a logical ring, and only the holder may transmit. Deterministic and robust, it ran at 4 and later 16 Mbit/s.
Token Ring was respected and expensive. Switched Ethernet removed its main advantage, freedom from collisions, at a fraction of the cost.
1985 · Radia Perlman, DEC · IEEE 802.1D
Bridges discover each other and block redundant links so frames cannot loop forever. Redundant LANs become safe to build.
Perlman designed the algorithm quickly and summed it up in a short poem, ‘Algorhyme’. She dislikes being called the ‘mother of the internet’.
16 Jan 1986 · US government-funded researchers · 21 attendees
Twenty-one people meet in San Diego. The IETF becomes the open body that writes internet standards, with no formal membership and no votes.
David Clark summed up the culture in 1992: rough consensus and running code. Chairs still sometimes gauge agreement by asking the room to hum.
1986 · National Science Foundation; Merit, IBM, MCI · 56 kbit/s → T1 → T3
A US research backbone links supercomputer centres and regional networks. Upgraded to T1 in 1988 and T3 in 1991, it becomes the internet's core.
NSFNET's acceptable use policy banned commercial traffic, which pushed companies to build their own networks and exchange points. Those became the commercial internet.
1987–1988 · David Payne (Southampton), Emmanuel Desurvire (Bell Labs) · EDFA · TAT-8
Erbium-doped fibre amplifiers boost light directly, without converting it to electricity. TAT-8, the first transatlantic fibre cable, opens in 1988.
Before EDFAs, long cables needed electronic regenerators at intervals. One amplifier can boost many wavelengths at once, which made DWDM possible.
Oct 1986 – 1988 · Van Jacobson, Michael Karels · Slow start · AIMD
In October 1986 throughput between Lawrence Berkeley Lab and UC Berkeley falls from 32 kbit/s to 40 bit/s. Jacobson's congestion control, added to TCP in 1988, stops the internet melting under load.
Hosts had been retransmitting into already full queues, making things worse. The fix lets each sender probe for capacity and back off on loss. Descendants such as CUBIC and Google's BBR run on every TCP connection.
2 Nov 1988 · Robert Tappan Morris · fingerd · sendmail
A self-spreading program infects around 6,000 of the internet's 60,000 hosts. CERT/CC is founded in response, the first computer emergency response team.
Morris said he wanted to measure the internet's size; a bug made it reinfect machines until they ground to a halt. He was the first person convicted under the US Computer Fraud and Abuse Act and later became an MIT professor.
Oct 1989 · John Moy, IETF · RFC 1131 · IP protocol 89
A link-state routing protocol: every router builds a map of its area and runs Dijkstra's shortest-path algorithm. It replaces RIP in most enterprise networks.
Edsger Dijkstra designed his algorithm in 1956 in about twenty minutes, sitting at a café in Amsterdam without pen and paper.
Jun 1989 · Kirk Lougheed (Cisco), Yakov Rekhter (IBM) · RFC 1105 · TCP/179
Networks exchange reachability between autonomous systems using policy rather than shortest path. BGP-4 (1994) still glues the global internet together.
The first design was sketched on two ketchup-stained napkins over lunch at an IETF meeting in Austin, Texas.
Mar 1989 · Tim Berners-Lee, Robert Cailliau, CERN · HTML · HTTP · URL
Berners-Lee proposes linked hypertext across CERN's network. By the end of 1990 he has written the first web server, browser and editor on a NeXT computer.
His manager, Mike Sendall, wrote ‘Vague but exciting’ on the cover. The NeXT that served the first website carried a handwritten label telling people not to power it down.
1990 · SynOptics, IEEE 802.3 · IEEE 802.3i · RJ45
Ethernet moves from coaxial cable to twisted pair wired in a star around a hub. Structured cabling and the RJ45 socket become standard.
SynOptics' LattisNet showed Ethernet could run over ordinary building wiring. The star also made faults easy to find: unplug one cable, not a whole segment.
1990 · Vinod Bhardwaj, Kalpana · Layer 2 switching
The first commercial Ethernet switch gives each port its own collision domain. Switches replace shared hubs through the 1990s.
The company was named after Bhardwaj's wife. Cisco bought Kalpana in 1994, a year after buying Crescendo, whose products became the Catalyst line.
Hypertext meets TCP/IP. The network leaves the lab and the money arrives.
1991 · Mark McCahill, University of Minnesota · TCP/70
A menu-driven way to find documents across the internet. It was simpler than the web and more popular at first.
It was named after the university's mascot. In 1993 Minnesota announced licence fees for some users, the same year CERN made the web free to all.
25 Aug 1991 · Linus Torvalds · GPL kernel
A Finnish student announces a free Unix-like kernel. Linux now runs most web servers, Android phones, cloud hosts and the control planes of many routers and switches.
His announcement described it as just a hobby, nothing big or professional. Cisco NX-OS and IOS XE, Arista EOS and Juniper's Junos Evolved all run on Linux.
1 Jul 1991 · Harri Holkeri, Radiolinja (Finland) · 2G · GSM
Digital mobile telephony launches. GSM brought the SIM card and roaming, and its GPRS data service put the internet on phones. 3G followed in Japan in 2001.
The first SMS was sent on 3 December 1992, when Vodafone engineer Neil Papworth typed ‘Merry Christmas’ on a PC to a colleague's phone in Newbury.
Jun 1991 · Phil Zimmermann · OpenPGP
Strong public-key encryption for email, released free. It brought cryptography to ordinary users years before the web padlock.
US prosecutors investigated Zimmermann for exporting munitions, since strong encryption was then classed as a weapon. MIT Press printed the source code as a book, and the case was dropped in 1996.
1991–1992 · ATM Forum, telcos · 53-byte cells
Asynchronous Transfer Mode carries voice, video and data in fixed 53-byte cells. Telcos backed it as the future of both LANs and WANs.
The 48-byte payload was a compromise: Europe wanted 32 bytes and the US wanted 64. Ethernet took the LAN, and ATM lingered in DSL and mobile backhaul.
1993 · Marc Andreessen, Eric Bina (NCSA); CERN · <img> · public domain
A free graphical browser shows images inline with text on Windows, Mac and Unix. On 30 April 1993 CERN releases the web software royalty-free. Growth goes vertical.
Andreessen proposed the img tag on a mailing list in February 1993 and shipped it before anyone had agreed.
Oct 1993 · Ralph Droms · RFC 1531 · UDP/67–68
Hosts receive an address, mask, gateway and DNS server automatically. Without it, joining Wi-Fi would mean typing four sets of numbers.
DHCP extended BOOTP, used by diskless workstations to find a boot server. Leases return addresses to the pool when a laptop leaves.
Sep 1993 · Vince Fuller, Tony Li, Yakov Rekhter; Kjeld Egevang, Paul Francis · RFC 1519 · RFC 1631
Classless addressing ends the wasteful Class A/B/C scheme and lets routes aggregate. NAT (1994) lets many hosts share one public address. Together they stretch IPv4 by decades.
By 1992 Class B networks were running out and backbone routing tables were growing faster than router memory. NAT was meant to be a stopgap.
1993 · Cisco · Lab exam
An expert certification with a hands-on lab, joined by the CCNA in 1998. Vendor certifications become the career path for network engineers.
CCIE numbering started at 1024, a nod to binary. The lab is still a single long day in front of a rack of equipment, in revised form.
1994 · Gil Shwed, Marius Nacht, Shlomo Kramer · Stateful inspection
A software firewall that tracks the state of each connection, not just individual packets, managed through a graphical policy editor. Stateful inspection becomes the baseline for every firewall since.
Shwed developed the idea during military service in Israel. Earlier packet filters, such as DEC's in the late 1980s, judged each packet in isolation.
Oct 1994 · Marc Andreessen, Jim Clark · Browser wars
The dominant browser of the mid-1990s. Netscape's August 1995 share offering roughly doubled on its first day and set off the dot-com boom.
Netscape released its source code in 1998, creating Mozilla. Navigator was retired in 2008; its lineage lives on in Firefox.
Feb 1995 · Taher Elgamal, Netscape · TCP/443 · HTTPS
Netscape encrypts traffic between browser and server so card numbers can cross the web. SSL 3.0 (1996) becomes TLS 1.0 in 1999.
SSL 1.0 was never released because of security flaws. The padlock icon trained a generation to look for HTTPS.
May 1995 · Brendan Eich, Netscape · ECMAScript
A scripting language for the browser, built in ten days. With later additions such as XMLHttpRequest, web pages became applications.
It was called Mocha, then LiveScript, then renamed to ride the hype around Sun's Java. The two languages have little in common.
30 Apr 1995 · NSF, commercial ISPs · NAPs · peering
Backbone traffic moves to commercial providers interconnecting at network access points. Amazon and eBay launch the same year.
ARPANET itself had been switched off in February 1990, its sites already moved to NSFNET.
Jun 1995 · IEEE 802.3 · IEEE 802.3u · z · ab · ae
100 Mbit/s over Category 5 cable. Gigabit (802.3z in 1998, 802.3ab over copper in 1999) and 10 Gigabit (802.3ae, 2002) follow.
Each step kept the same frame format, so software and tools carried straight over. That backwards compatibility is why Ethernet outlasted every rival.
Dec 1995 · Steve Deering, Robert Hinden · RFC 1883 → RFC 8200
128-bit addresses, about 3.4 × 10³⁸ of them. Finalised as RFC 8200 in 2017, it now carries traffic for close to half of Google's users.
There was never a deployed IPv5. Version 5 had been assigned to the experimental Internet Stream Protocol, ST-II.
Feb 1996 · Yakov Rekhter and others · RFC 1918
10.0.0.0/8, 172.16.0.0/12 and 192.168.0.0/16 are reserved for private networks. Almost every home router hands out a 192.168 address.
The 172.16/12 block is the one people forget, which is exactly why it turns up in exam questions.
Feb 1996 · Pradeep Sindhu · M40 · Junos
Juniper's M40 (1998) forwards packets in custom ASICs at line rate under a FreeBSD-based OS, Junos. The core-router market has to speed up.
Sindhu came from Xerox PARC. Separating the control plane (routing software) from the forwarding plane (silicon) became the standard router architecture.
1996 · Jeff Hussey, Michael Almquist · BIG-IP
BIG-IP spreads web traffic across server farms and checks their health. Application delivery controllers become a standard layer in the data centre.
The company name comes from the most violent rating on the Fujita tornado scale.
1996 · Ciena and others · ITU-T wavelength grid
Dense wavelength-division multiplexing sends many colours of light down one fibre. Ciena's first 16-channel system went to Sprint in 1996; modern systems carry tens of terabits per fibre pair.
Because EDFAs amplify all the wavelengths together, adding colours multiplied capacity without laying new cable.
1997 · Joseph Lechleider (Bellcore), CableLabs · ADSL · DOCSIS
DSL squeezes megabits through telephone copper and DOCSIS (1997) does the same over cable TV networks. Always-on connections replace dial-up modems.
Lechleider's late-1980s insight was to make download faster than upload, which reduced interference between pairs in the same cable. Asymmetry still defines most home connections.
Jun 1997 · Vic Hayes (chair); CSIRO's John O'Sullivan · IEEE 802.11 · 2.4 GHz
The first 802.11 standard runs at 2 Mbit/s. 802.11b (1999) reaches 11 Mbit/s and the Wi-Fi Alliance starts certifying equipment.
‘Wi-Fi’ was a brand name from the agency Interbrand and does not stand for anything. Australia's CSIRO won patents on key techniques that came out of radio astronomy work hunting for exploding black holes.
1998 · IEEE 802.1 · IEEE 802.1Q · 12-bit VID
A 4-byte tag lets one switch carry many isolated LANs and trunks carry them between switches. Cisco's proprietary ISL is gradually retired.
The VLAN ID is 12 bits, hence 4,094 usable VLANs, and hence VXLAN later on with 24 bits and about 16 million segments.
1998 · Nortel · SynOptics + Wellfleet
Canada's Nortel pays about $9 billion for Bay Networks, betting on data networking. At its 2000 peak Nortel made up about a third of the Toronto stock index.
Nortel filed for bankruptcy in 2009. Its patents sold for $4.5 billion in 2011 to a consortium including Apple and Microsoft.
1998 · Tom Leighton, Danny Lewin · CDN
Copies of content are served from caches close to users. CDNs now deliver most web and video traffic.
Lewin, the co-founder and CTO, was killed aboard American Airlines Flight 11 on 11 September 2001. Akamai's network carried much of the surge in news traffic that day.
Sep 1998 · Jon Postel · 13 root server identities
Management of names, numbers and the DNS root moves from a US government contract to a non-profit, ICANN.
In January 1998 Postel asked eight of the twelve root server operators to take the root zone from his server instead of Network Solutions. He called it a test. He died that October, weeks after ICANN was formed.
4 Sep 1998 · Larry Page, Sergey Brin · PageRank
PageRank uses the web's own links to rank pages. Google goes on to build some of the largest private networks and data centres on Earth.
Andy Bechtolsheim, co-founder of Sun and later of Arista, wrote a $100,000 cheque to Google Inc. before the company legally existed.
21 Jul 1999 · Apple, Lucent · 802.11b · 11 Mbit/s
Apple sells AirPort base stations and iBook cards at consumer prices. Laptop makers follow, and hotspots appear in cafés and airports.
At the launch Steve Jobs passed an iBook through a hoop to show there were no wires.
Mar 2000 · Cisco, the market · NASDAQ −78%
In March 2000 Cisco briefly becomes the world's most valuable company, worth over half a trillion dollars. Within two years the NASDAQ has lost about three-quarters of its value.
The bust left huge amounts of unused fibre in the ground. That cheap dark fibre later carried the broadband and video boom.
Broadband, Wi-Fi and smartphones. The network becomes ambient and video starts to dominate.
Jan 2001 · Cisco tag switching, Ipsilon, IETF · RFC 3031
Packets carry short labels so routers switch them along pre-set paths. MPLS VPNs and traffic engineering become the backbone of carrier services.
It began as a way to make routers as fast as ATM switches. By the time it was standardised, silicon made plain IP lookups fast too, so MPLS survived on its VPN and traffic-engineering features.
Jun 2003 · IEEE 802.3 · IEEE 802.3af · 15.4 W
Power travels down the data cable. IP phones, access points and cameras need no local socket, and 802.3bt (2018) reaches 90 W.
PoE is why ceilings are full of access points: one cable run to the switch is cheaper than a cable plus an electrician.
25 Jan 2003 · Unknown author · UDP/1434 · 376 bytes
A worm in a single UDP packet infects around 75,000 servers in about ten minutes, doubling roughly every 8.5 seconds.
It carried no payload beyond spreading, yet the traffic alone disrupted cash machines, airline check-in and much of South Korea's internet. A patch had been available for six months.
2004 · Andy Bechtolsheim, David Cheriton, Ken Duda · EOS · merchant silicon
Arista builds data-centre switches on merchant silicon, running EOS, a Linux-based OS that exposes its state to software. Cloud providers buy them by the tens of thousands.
Founded as Arastra. Bechtolsheim and Cheriton had sold an earlier switch start-up, Granite Systems, to Cisco in 1996.
2000–2007 · Ken and Michael Xie (Fortinet); Nir Zuk (Palo Alto Networks) · App-ID · FortiGate
Fortinet (2000) folds intrusion prevention, antivirus and VPN into one box on custom silicon. Palo Alto Networks (2005) classifies traffic by application and user instead of port.
Zuk had been a principal engineer at Check Point, working on stateful inspection, before setting out to replace it.
2005–2007 · Chad Hurley, Steve Chen, Jawed Karim; Netflix · Video > 60% of traffic
YouTube launches in 2005 and Netflix starts streaming in 2007. Video becomes the majority of internet traffic and drives CDN and peering growth.
The first YouTube video, ‘Me at the zoo’, is 19 seconds long and was filmed at San Diego Zoo.
Mar 2006 · Amazon Web Services · S3 · EC2 · VPC
Amazon rents storage (S3, March 2006) and servers (EC2, August 2006) by the hour. Virtual private clouds (2009) move network design into software and APIs.
Cloud data centres forced new designs: leaf-spine fabrics, overlays such as VXLAN, and custom switches built by the operators themselves.
29 Jun 2007 · Apple · EDGE · Wi-Fi
A full web browser in a pocket. Mobile data traffic starts growing at rates carriers had not planned for.
The first iPhone lacked 3G and used the slower EDGE network, and AT&T's network struggled in some US cities.
Mar 2008 · Nick McKeown, Martin Casado, Scott Shenker · Controller · flow tables
A Stanford paper proposes switches whose forwarding tables are programmed by an external controller. Software-defined networking spreads to data centres and WANs.
Casado's company Nicira sold to VMware for $1.26 billion in 2012. In 2013 Google revealed that B4, its inter-data-centre WAN, ran on SDN.
2008 · Cisco · Nexus 7000 · ASR 1000
Cisco moves its operating systems onto Linux. NX-OS ships with the Nexus 7000 and IOS XE with the ASR 1000, bringing process isolation and APIs.
Classic IOS was one monolithic image, where a single misbehaving process could take down the box. On Linux, features can restart independently.
14 Dec 2009 · TeliaSonera (Stockholm, Oslo) · 3GPP Release 8 · all-IP
The first commercial LTE networks launch. 4G is all-IP, so voice becomes a VoIP service (VoLTE) on the same network as data.
LTE ended the split between a circuit-switched voice core and a packet data core that mobile networks had carried since GSM.
3 Feb 2011 · IANA, the regional registries · Last five /8s
The central pool of IPv4 addresses is exhausted, and each regional registry receives one final /8. World IPv6 Launch follows on 6 June 2012.
RIPE NCC, which serves Europe, handed out its last block in 2019. IPv4 addresses now trade on a secondary market.
2006–2012 · IETF; Michael DeHaan (Ansible) · NETCONF · YANG · Python
NETCONF (2006) and the YANG data modelling language (2010) give devices structured APIs. Python libraries and Ansible (2012) begin replacing copy-and-paste CLI work.
Python is named after Monty Python's Flying Circus, not the snake.
Encryption by default, networks driven by APIs, and fabrics built for AI.
7 Apr 2014 · Found by Google and Codenomicon · CVE-2014-0160
A missing bounds check in OpenSSL's heartbeat feature lets attackers read server memory, including private keys. Around a sixth of secure web servers are exposed.
The bug was committed on New Year's Eve 2011. OpenSSL was maintained largely by volunteers, and Heartbleed led to new funding for critical open-source projects.
May 2015 · IETF; Google's SPDY · RFC 7540
Multiplexed streams over one connection, header compression and binary framing, based on Google's SPDY.
Browsers only implemented HTTP/2 over TLS, which quietly pushed more of the web towards encryption.
Dec 2015 · ISRG; Josh Aas, Eric Rescorla and others · ACME · RFC 8555
Free, automated TLS certificates. Within a few years the share of encrypted page loads in Firefox goes from under half to over 80 per cent.
Run by a non-profit, it became the largest certificate authority in the world. Its ACME protocol is now an IETF standard.
21 Oct 2016 · Three college students · Telnet default passwords
A botnet of cameras and home routers with default passwords floods DNS provider Dyn, disrupting Twitter, Netflix, Reddit and others.
Its authors built it to attack Minecraft servers. After the source code leaked, copies multiplied.
2017 · Viptela, VeloCloud and others · Overlay · central controller
Branch networks are steered by central controllers across broadband, LTE and MPLS. Cisco buys Viptela and VMware buys VeloCloud in 2017.
SD-WAN brought SDN ideas to the enterprise WAN, where expensive MPLS circuits had been the default for 15 years.
Aug 2018 · IETF TLS working group · RFC 8446
One round-trip handshakes, forward secrecy by default and removal of weak ciphers. Middleboxes that inspected traffic had to adapt.
During testing, some middleboxes broke on the new version number, so a TLS 1.3 handshake disguises itself to look like a TLS 1.2 session resumption.
3 Apr 2019 · Carriers in South Korea and the US; Wi-Fi Alliance · 3GPP Rel-15 · 802.11ax
5G launches in April 2019 and Wi-Fi 6 certification starts in September. Both use OFDMA to serve many devices at once.
The Wi-Fi Alliance renamed standards by generation in 2018, so 802.11n, ac and ax became Wi-Fi 4, 5 and 6.
23 May 2019 · SpaceX · LEO · laser links
The first 60 production Starlink satellites launch. Low orbits cut latency to tens of milliseconds, and newer satellites pass traffic between each other by laser.
Satellite was one of the three networks in TCP's first internetworking test in 1977. Forty years later it returned as a mass-market access network.
Mar 2020 · Everyone · Peak-hour traffic
Lockdowns push traffic up by around 30 per cent on many networks within weeks as work, school and family move to video calls. The networks hold.
The European Commission asked streaming services to reduce quality, and Netflix and YouTube cut default bitrates in Europe.
May 2021 · Jim Roskind (Google); IETF · RFC 9000 · RFC 9114 · UDP/443
Transport moves into user space over UDP with encryption built in and no head-of-line blocking between streams. HTTP/3 (2022) runs on it.
Roskind designed QUIC at Google around 2012. A large share of web traffic now runs over UDP, which older firewalls treated with suspicion.
4 Oct 2021 · Meta · AS32934
A maintenance command cuts Facebook's backbone, and its DNS servers withdraw their BGP routes. Facebook, Instagram and WhatsApp vanish for about six hours.
Engineers had trouble getting into data centres because the building access systems depended on the same network.
Dec 2022 · University of Southampton spin-out Lumenisity; Microsoft · Light through air
Light travels through air at the fibre's centre instead of glass, cutting latency by about a third. Microsoft buys Lumenisity in 2022 to deploy it.
Lumenisity came out of Southampton's Optoelectronics Research Centre, the same group that developed the erbium-doped amplifier.
2023–2025 · IEEE 802.3; Ultra Ethernet Consortium · IEEE 802.3df · UEC 1.0
AI training clusters need lossless, low-latency fabrics joining tens of thousands of GPUs. 800 Gb Ethernet is standardised in 2024, and the Ultra Ethernet Consortium (2023) publishes its 1.0 specification in 2025.
Fifty years after Metcalfe's 2.94 Mbit/s coax, the same frame format is being stretched to carry the traffic of AI clusters.
Jan 2024 · Wi-Fi Alliance · 802.11be · 320 MHz · MLO
Certification starts in January 2024. Multi-link operation lets a device use the 2.4, 5 and 6 GHz bands at the same time.
Its theoretical peak of about 46 Gbit/s is more than 20,000 times the 2 Mbit/s of the first 802.11 standard in 1997.
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