Today, it is 50 years (1973-05-22) since Ethernet was invented at Xerox PARC (Palo Alto Research Center), in Palo Alto, California. This date specifically references a memo written by Bob Metcalfe (1946 – ). Ether refers to an omnipresent, luminiferous aether, that acts as a passive medium for the propagation of electromagnetic waves. In 1975, Xerox filed a patent application listing Metcalfe, David Boggs (1950 – 2022) , Chuck Thacker (1943 – 2017) and Butler Lampson (1943 – ) as Ethernet inventors.
Metcalfe’s law states that the impact of a telecommunications network is proportional to the square of the number of nodes, initially expressed as compatible communicating devices in, later as connected users of, the system (n2). The law was first proposed in 1983-12, in a 3Com sales presentation, given by Robert Metcalfe. The law was popularized by George Gilder in a 1993-09-13 Forbes article which specifically associated it with Ethernet users.
Some feel that this law overstates the case, in that not all nodes are born equal. Specifically, reference is made to the Dunbar number, originally expressed as a cognitive limit to the number of people with whom one can maintain stable social relationships. Anthropologist Robin Dunbar (1947 – ), who devised the concept, places the limit at about 150, for people. In terms of this weblog post, I have stated that I will know that I am doing something wrong, if the number of readers exceeds 100. It is only intended for family and friends, with whom I wish to maintain stable social relationships. In addition, it allows for, say, fifty people to disown me (or the weblog), for various reasons, real or imagined. In terms of Ethernet nodes, it is easier to reach some in contrast to others. Indeed, most people place considerable effort in evading contact by spammers, and other forms of Internet lowlife.
António Madureira, Frank den Hartog, Harry Bouwman and Nico Baken have, in 2013, empirically validated Metcalfe’s law, specifically looking at how Internet usage patterns changed over time, See: Information Economics and Policy, 25 (4): 246–256.
Ethernet was commercially available, starting in 1980. It was standardized in 1983 as IEEE 802.3. New versions of Ethernet have increased bit rates, the number of nodes connected, and link distances, yet retain considerable backward compatibility. Ethernet has largely replaced competing wired local-area network (LAN) technologies, such as the token-ring and aloha networks.
An Ethernet connection is made using a cable fitted with a male plug connector at both ends. One end of the connector (most often a 8P8C plug) usually attaches to a device (such as a laptop computer) fitted with a 8P8C jack, while the plug, at the other end is attached to the jack of a switch. The term RJ45 connector/ plug/ jack is often used. The original (telephone) RJ45 connector featured a key that disallowed 8P8C connectors. These RJ45 connectors are obsolete, but continue to be referenced in the language. There are variations in the termination of the wiring inside 8P8C connectors, with two distinct flavours, officially known as T568A and T568B. These are defined in ANSI/TIA-568. I have never known anyone who uses anything but B.
Connector installation improves with practice. We use purpose built tools and a tester to ensure that cables function properly.
Propaganda
It can be difficult for people to obtain appropriate information about Ethernet connections, and Internet operations, more generally .
Many people I associate with are surprised that Cliff Cottage, our residence, is wired with CAT 6A Ethernet cable. Gratuitous advice: If it is too difficult to put Ethernet cable inside a wall, fasten it outside, immediately above a baseboard. We have done this in select locations. We have also allowed the cable to be fitted inside door molding.
We use a power-over-Ethernet (PoE) switch with 24 ports, that are fitted to our server rack. This allows us to send data and electrical power in the same cable. Users in our household each have a PoE UniFi Flex Mini switch with five ports, operating at gigabit speed. We also have three UniFi Wi-Fi 6 lite access points at appropriate locations in the house, so that all portable/ hand-held devices can connect to the Internet..
Note: The publication date is also World Goth Day #15. It will not have a weblog post devoted to it this year, but will return to explore Gothic architecture on World Goth Day #16, 2024-05-22. As compensation, a weblog post about Wave Gotik Treffen, a Leipzig music festival, will be published 2023-05-27.