Editing Small Form-factor Pluggable (section)

== QSFP ==
[[file:QSFP-40G-SR4_Transceiver.jpg|thumb|QSFP+ 40&nbsp;Gb transceiver]]

''Quad Small Form-factor Pluggable'' (''QSFP'') transceivers are available with a variety of transmitter and receiver types, allowing users to select the appropriate transceiver for each link to provide the required ''optical reach'' over [[multi-mode fiber|multi-mode]] or [[single-mode fiber]].

; {{nowrap|4 Gbit/s}}: The original QSFP document specified four channels carrying [[Gigabit Ethernet]], 4GFC ([[FiberChannel]]), or DDR [[InfiniBand]].<ref name="inf8438">{{cite web|url=http://ftp.seagate.com/sff/INF-8438.PDF|title=QSFP Public Specification (INF-8438)|last1=SFF Committee|publisher=SFF Committee|page=12|access-date=2016-06-22}}</ref>
; {{nowrap|40 Gbit/s}} (QSFP+): QSFP+ is an evolution of QSFP to support four {{nowrap|10 Gbit/s}} channels carrying [[10 Gigabit Ethernet]], 10GFC [[FiberChannel]], or QDR [[InfiniBand]].<ref name="sff8436">{{cite web|last1=SFF Committee|title=QSFP+ 10&nbsp;Gbs 4X Pluggable Transceiver (SFF-8436)|url=http://ftp.seagate.com/sff/SFF-8436.PDF|access-date=2016-06-22|page=13}}</ref> The 4 channels can also be combined into a single [[40 Gigabit Ethernet#Connectors|40 Gigabit Ethernet]] link.
; {{nowrap|50 Gbit/s}} (QSFP14): The QSFP14 standard is designed to carry FDR [[InfiniBand]], [[Serial Attached SCSI|SAS-3]]<ref>{{cite web|last1=SFF Committee|title=QSFP+ 14&nbsp;Gb/s 4X Pluggable Transceiver Solution (QSFP14)|url=http://ftp.seagate.com/sff/SFF-8685.PDF|access-date=2016-06-22|page=5}}</ref> or 16G Fibre Channel.
; {{nowrap|100 Gbit/s}} (QSFP28): The QSFP28 standard<ref name="sff-8665" /> is designed to carry [[100 Gigabit Ethernet]], EDR [[InfiniBand]], or 32G Fibre Channel. Sometimes this transceiver type is also referred to as ''QSFP100'' or ''100G QSFP''<ref>{{Cite web |url=https://www.arista.com/assets/data/pdf/Arista100G_TC_QA.pdf |title=100G Optics and Cabling Q&A Document |website=www.arista.com |publisher=[[Arista Networks]]}}</ref> for sake of simplicity.
; {{nowrap|200 Gbit/s}} (QSFP56): QSFP56 is designed to carry [[200 Gigabit Ethernet]], HDR [[InfiniBand]], or 64G Fibre Channel. The biggest enhancement is that QSFP56 uses four-level pulse-amplitude modulation ([[PAM-4]]) instead of [[non-return-to-zero]] (NRZ). It uses the same physical specifications as QSFP28 (SFF-8665), with electrical specifications from SFF-8024<ref name="sff-8024">{{cite web|url=https://members.snia.org/document/dl/26423|title=SFF-8024: Management Interface for Cabled Environments|date=2019-02-14|publisher=SNIA SFF Committee|access-date=2019-04-04|version=4.6}}</ref> and revision 2.10a of SFF-8636.<ref name="sff-8636r2.9.2draft">{{cite web|url=https://members.snia.org/document/dl/26418|title=Management Interface for 4-lane Modules and Cables|date=2019-09-24|series=SFF-8636|publisher=SNIA SFF Committee|access-date=2019-10-11|edition=Rev 2.10a}}</ref> Sometimes this transceiver type is referred to as ''200G QSFP''<ref>{{Cite web|url=https://www.arista.com/assets/data/pdf/Datasheets/Arista-400G_Optics_FAQ.pdf|title=Arista 400G Transceivers and Cables: Q&A|website=www.arista.com|publisher=Arista Networks, Inc.|access-date=2019-04-04}}</ref> for sake of simplicity.

Switch and router manufacturers implementing QSFP+ ports in their products frequently allow for the use of a single QSFP+ port as four independent [[10 Gigabit Ethernet]] connections, greatly increasing port density. For example, a typical 24-port QSFP+ [[19-inch rack|1U]] switch would be able to service 96x10GbE connections.<ref>{{Cite web|url=http://www.cisco.com/c/en/us/products/collateral/switches/nexus-5624q-switch/datasheet-c78-733100.html|title=Cisco Nexus 5600 specifications}}</ref><ref>{{Cite web|url=https://www.finisar.com/active-optical-cables/fcbn510qe2cxx|title=Finisar 4 x 10GbE fanout QSFP}}</ref><ref>{{Cite web|url=https://www.arista.com/assets/data/pdf/40G_FAQ.pdf|title=Arista 40Gb port to 4 x 10GbE breakout}}</ref> There also exist fanout cables to adapt a single QSFP28 port to four independent [[25 Gigabit Ethernet]] SFP28 ports (QSFP28-to-4×SFP28)<ref>{{Cite web|url=http://www.prolabs.com/products/direct-attach-cables/msa_standard/QSFP28-SFP28/QSFP28-4XSFP28-DAC-3M-NC/|title=QSFP28-to-SFP28 breakout}}</ref> as well as cables to adapt a single QSFP56 port to four independent [[50 Gigabit Ethernet]] SFP56 ports (QSFP56-to-4×SFP56).<ref>{{cite web|url=https://www.te.com/usa-en/product-4-2334236-1.html|title=QSFP56 : 4-2334236-1 Pluggable I/O Cable Assemblies|website=TE Connectivity}}</ref>