Editing Backplane (section)

==Midplane==
Some backplanes are constructed with slots for connecting to devices on both sides, and are referred to as midplanes. This ability to plug cards into either side of a midplane is often useful in larger systems made up primarily of modules attached to the midplane.

Midplanes are often used in computers, mostly in [[blade server]]s, where server blades reside on one side and the peripheral (power, networking, and other I/O) and service modules reside on the other. Midplanes are also popular in networking and telecommunications equipment where one side of the chassis accepts system processing cards and the other side of the chassis accepts network interface cards.

Orthogonal midplanes connect vertical cards on one side to horizontal boards on the other side.<ref>Kevin O’Connor.
[http://www.ecnmag.com/articles/2010/12/orthogonal-backplane-connector-technology-offers-design-flexibility "Orthogonal Backplane Connector Technology Offers Design Flexibility"] {{Webarchive|url=https://web.archive.org/web/20130704032443/http://www.ecnmag.com/articles/2010/12/orthogonal-backplane-connector-technology-offers-design-flexibility |date=4 July 2013 }}.
2010.</ref><ref>Pete.
[http://www.connector.com/2011/02/high-speed-orthogonal-connectors-optimize-signal-integrity/ "High-Speed Orthogonal Connectors Optimize Signal Integrity"] {{Webarchive|url=https://web.archive.org/web/20150428122800/http://www.connector.com/2011/02/high-speed-orthogonal-connectors-optimize-signal-integrity/ |date=28 April 2015 }}.
2011.</ref>
One common orthogonal midplane connects many vertical telephone [[line card]]s on one side, each one connected to copper telephone wires, to a horizontal communications card on the other side.<ref>[http://www.fci.com/en/products/backplane-connectors/airmax-vs-backplane/airmax-vs-orthogonal.html "AirMax VS Orthogonal"] {{Webarchive|url=https://web.archive.org/web/20140614151402/http://www.fci.com/en/products/backplane-connectors/airmax-vs-backplane/airmax-vs-orthogonal.html |date=14 June 2014 }}.</ref>

A "virtual midplane" is an imaginary plane between vertical cards on one side that directly connect to horizontal boards on the other side; the card-slot aligners of the card cage and self-aligning connectors on the cards hold the cards in position.<ref>
Michael Fowler.
[http://electronicdesign.com/boards/virtual-midplane-realizes-ultrafast-card-interconnects "Virtual Midplane Realizes Ultrafast Card Interconnects"].
Electronic Design.
2002.
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Some people use the term "midplane" to describe a board that sits between and connects a hard drive hot-swap backplane and redundant power supplies.<ref>[https://archive.today/20140329190529/http://h20000.www2.hp.com/bizsupport/TechSupport/Document.jsp?lang=en&cc=us&objectID=c00881823&jumpid=reg_r1002_usen_c-001_title_r0001 "HP StorageWorks Modular Smart Array 70 Enclosure - Replacing the Backplane"].</ref><ref>
[http://download.intel.com/support/motherboards/server/s5520ur/sb/r2612ur_service_guide_14.pdf "Intel Server System SR2612UR Service Guide"].
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