Editing 10BASE2 (section)

==Network design==
10BASE2 coax cables have a maximum length of {{convert|185|m|ft}}. The maximum practical number of nodes that can be connected to a 10BASE2 segment is limited to 30<ref>IEEE 802.3 ''10.7.2.2 MAU placement''</ref> with a minimum distance of {{convert|0.5|m|in}} between devices.<ref>IEEE 802.3 ''10.7.2.1 Cable sectioning''</ref> In a 10BASE2 network, each stretch of cable is connected to the [[Medium Attachment Unit|transceiver]] (which is usually built into the network adaptor) using a BNC [[T-connector]],{{efn|Other connectors such as [[EAD socket]]s were promoted as a less error-prone alternative to BNC connectors.}} with one stretch connected to each female connector of the T. The T-connector must be plugged directly into the network adaptor with no cable in between.

As is the case with most other high-speed [[Transmission line|buses]], Ethernet segments have to be [[Electrical termination|terminated]] with a [[resistor]] at each end. Each end of the cable has a {{val|50|ul=Ω}} resistor attached. Typically this resistor is built into a male [[BNC connector|BNC]] and attached to the last device on the bus. This is most commonly connected directly to the T-connector on a workstation.{{efn|A few devices such as Digital's DEMPR and DESPR have a built-in terminator and so can only be used at one physical end of the cable run.}} If termination is missing, or if there is a break in the cable, the [[alternating current|AC]] signal on the bus is reflected, rather than dissipated, when it reaches the end. This reflected signal is indistinguishable from a collision, so no communication can take place.

Some terminators have a metallic chain attached to them for grounding purposes. The cable should be [[ground (electricity)|grounded]] only at one end. Grounding the terminators at both may produce a [[Ground loop (electricity)|ground loop]] and can cause network outages or data corruption when swells of electricity traverse the coaxial cabling's outer shield.

When wiring a 10BASE2 network, special care has to be taken to ensure that cables are properly connected to all T-connectors. Bad contacts or shorts are especially difficult to diagnose. A failure at any point of the network cabling tends to prevent all communications. For this reason, 10BASE2 networks can be difficult to maintain and were often replaced by [[10BASE-T]] networks, which (provided [[category 5 cable]] or better was used) also provided a good upgrade path to [[100BASE-TX]].