Editing 10BASE5

{{Short description|First commercially available variant of Ethernet}}
{{use mdy dates|date=September 2021}}
{{Use American English|date=May 2020}}

[[Image:ThicknetTransceiver.jpg|thumb|10BASE5 [[vampire tap]] [[Medium Attachment Unit]] (transceiver)]]
[[Image:10Base5transcievers.jpg|thumb|10BASE5 transceivers, cables, and tapping tool]]

'''10BASE5''' (also known as '''thick Ethernet''' or '''thicknet''') was the first commercially available variant of [[Ethernet]]. The technology was standardized in 1982<ref name=VonBurg2003>{{cite journal |last=von Burg |first=Urs |last2=Kenney |first2=Martin |title=Sponsors, Communities, and Standards: Ethernet vs. Token Ring in the Local Area Networking Business |journal=Industry & Innovation |date=December 2003 |volume=10 |issue=4 |pages=351–375 |doi=10.1080/1366271032000163621 |url=http://hcd.ucdavis.edu/faculty/webpages/kenney/articles_files/Sponsors,%20Communities,%20and%20Standards:%20Ethernet%20vs.%20Token%20Ring%20in%20the%20Local%20Area%20Networking%20Business.pdf |archive-url=https://web.archive.org/web/20111206202221/http://hcd.ucdavis.edu/faculty/webpages/kenney/articles_files/Sponsors,%20Communities,%20and%20Standards:%20Ethernet%20vs.%20Token%20Ring%20in%20the%20Local%20Area%20Networking%20Business.pdf |archive-date=December 6, 2011 |url-status=dead |access-date=17 February 2014 |df=mdy }}</ref> as [[IEEE 802.3]]. 10BASE5 uses a thick and stiff coaxial cable<ref name="Belden9880">{{cite web |last1=Belden |title=Product 9880 |url=https://catalog.belden.com/techdata/EN/9880_techdata.pdf |website=catalog.belden.com |publisher=Belden |access-date=8 April 2023}}</ref> up to {{convert|500|m|sp=us}} in length. Up to 100 stations can be connected to the cable using [[vampire tap]]s and share a single [[collision domain]] with 10&nbsp;[[megabit per second|Mbit/s]] of [[Bandwidth (computing)|bandwidth]] shared among them. The system is difficult to install and maintain.

10BASE5 was superseded by much cheaper and more convenient alternatives: first by [[10BASE2]] based on a thinner coaxial cable (1985), and then, once [[Ethernet over twisted pair]] was developed, by [[10BASE-T]] (1990) and its successors [[100BASE-TX]] and [[1000BASE-T]]. In 2003, the IEEE 802.3 working group [[deprecated]] 10BASE5 for new installations.<ref>IEEE 802.3-2005 ''8. Medium attachment unit and baseband medium specifications, type 10BASE5''</ref>

==Name origination==
The name ''10BASE5'' is derived from several characteristics of the physical medium. The ''10'' refers to its transmission speed of 10&nbsp;Mbit/s. The ''BASE'' is short for [[baseband]] signaling (as opposed to [[broadband]]{{efn|The choice for ''broadband'' as the opposite is exemplified by Ethernet standards such as [[10BROAD36]]. Later, the term ''broadband'' came to be used more commonly for different concepts, and the terms ''[[passband]]'' or ''[[modulated]]'' would be used to describe non-baseband signaling.}}), and the ''5'' stands for the maximum segment length of {{convert|500|m|sp=us}}.<ref>{{cite book|last=Stallings|first=William|title=Local and Metropolitan Area Networks|year=1993|publisher=Macmillan Publishing Company|isbn=0-02-415465-2|pages=[https://archive.org/details/localmetropolita0000stal/page/107 107]|url=https://archive.org/details/localmetropolita0000stal/page/107}}</ref>

==Network design and installation==
For its [[Ethernet physical layer|physical layer]] 10BASE5 uses cable similar to RG-8/U [[coaxial cable]] but with extra braided shielding. This is a stiff, {{convert|0.375|in|adj=on}} diameter cable with an impedance of 50&nbsp;[[Ohm (unit)|ohms]], a solid center conductor, a foam insulating filler, a shielding braid, and an outer jacket. The outer jacket is often yellow-to-orange [[fluorinated ethylene propylene]] (for fire resistance) so it often is called "yellow cable", "orange hose", or sometimes humorously "frozen yellow garden hose".<ref>{{cite book |title=All-in-One Networking+ Certification Exam Guide |author=Mike Meyers |edition=3rd |publisher=McGraw-Hill |date=2004 |page=79}}</ref> 10BASE5 coaxial cables had a maximum length of {{convert|500|m|sp=us}}. Up to 100 nodes could be connected to a 10BASE5 segment.<ref>{{cite web |url= http://computernetworkingnotes.com/n_plus_certifications/10base_ethernet.htm |title= 5-4-3 rule |access-date= 2010-06-30 |archive-date= June 11, 2010 |archive-url= https://web.archive.org/web/20100611104753/http://computernetworkingnotes.com/n_plus_certifications/10base_ethernet.htm |url-status= dead }}</ref>

[[Transceiver]] nodes can be connected to cable segments with [[N connector]]s, or via a ''[[vampire tap]]'', which allows new [[node (networking)|node]]s to be added while existing connections are live. A vampire tap clamps onto the cable, a hole is drilled through the outer shielding, and a spike is forced to pierce the outer three layers and contact the inner conductor while other spikes bite into the outer braided shield. Care is required to keep the outer shield from touching the spike; installation kits include a "coring tool" to drill through the outer layers and a "braid pick" to clear stray pieces of the outer shield.

Transceivers should be installed only at precise 2.5-meter intervals. This distance was chosen to ''not'' correspond to the signal's wavelength; this ensures that the reflections from multiple taps are not in phase.<ref>{{Citation | title = IEEE Standard 802.3-1985 | pages = 121 | isbn = 0-471-82749-5 | publisher = [[IEEE]] | author = Technical Committee on Computer Communications of the IEEE Computer Society | year = 1985}}</ref> These suitable points are marked on the cable with black bands. The cable is required to be one continuous run; T-connections are not allowed.

As is the case with most other high-speed buses, segments must be [[Electrical termination|terminated]] at each end. For coaxial-cable-based Ethernet, each end of the cable has a 50&nbsp;ohm resistor attached. Typically this resistor is built into a male N connector and attached to the cable's end just past the last device. With termination missing, or if there is a break in the cable, the signal on the bus will be reflected, rather than dissipated when it reaches the end. This reflected signal is indistinguishable from a [[Carrier-sense multiple access with collision detection|collision]] and prevents communication.

==Disadvantages==
Adding new stations to the network is complicated by the need to pierce the cable accurately. The cable is stiff and difficult to bend around corners. One improper connection can take down the whole network and finding the source of the trouble is difficult.<ref>{{cite web |url=http://hcd.ucdavis.edu/faculty/webpages/kenney/articles_files/Sponsors,%20Communities,%20and%20Standards:%20Ethernet%20vs.%20Token%20Ring%20in%20the%20Local%20Area%20Networking%20Business.pdf |title=Sponsors, Communities, and Standards: Ethernet vs. Token Ring in the Local Area Networking Business |archive-url=https://web.archive.org/web/20120618164900/http://hcd.ucdavis.edu/faculty/webpages/kenney/articles_files/Sponsors,%20Communities,%20and%20Standards:%20Ethernet%20vs.%20Token%20Ring%20in%20the%20Local%20Area%20Networking%20Business.pdf |archive-date=2012-06-18 |url-status=dead |author1=Urd Von Burg |author2=Martin Kenny |date=December 2003 |access-date=2012-03-25 }}</ref>

==See also==
{{Commons category}}
* [[Classic Ethernet]]
* [[EAD-socket]]

==Notes==
{{notelist}}

==References==
{{Reflist}}

{{Ethernet}}

[[Category:Ethernet standards]]