GBIC, SFP, SFP+ and XFP are all terms for a type of transceiver optics that plugs into a special port on a switch, router or other network device to convert the port to a copper or fiber interface. The commonly used SFP, SFP+ and XFP are all with LC connector. SFP and SFP+ with an identical pinout that is different with XFP optics. Both SFP+ and XFP with DDM function as default, whereas SFP partly support DDM function.
Comparison: SFP vs GBIC vs SFP+ vs XFP
	
		
			|  Optics Type | 
			Standard | 
			Data Rate | 
			Wavelength | 
			Fiber Type | 
			Max Distance | 
			Typical Connector | 
			DOM | 
			Operating Temperature | 
		
		
			|  SFP | 
			SFP MSA | 
			155Mbps 
			622Mbps 
			1.25Gbps 
			2.125Gbps 
			2.5Gbps 
			3Gbps 
			4.25Gbps | 
			850nm 
			1310nm 
			1550nm 
			CWDM 
			DWDM 
			BIDI | 
			OM1 
			OM2 
			OS1 
			OS2 | 
			160km | 
			LC   SC    RJ-45 | 
			No or Yes | 
			Commercial 
			Industrial | 
		
		
			|  GBIC | 
			GBIC MSA | 
			155Mbps 
			622Mbps 
			1.25Gbps | 
			850nm 
			1310nm 
			1550nm 
			CWDM 
			DWDM 
			BIDI | 
			OM1 
			OM2 
			OS1 
			OS2 | 
			120km | 
			SC   RJ-45 | 
			No | 
			Commercial 
			Industrial | 
		
		
			|  SFP+ | 
			IEE802.3ae 
			SFF-8431 
			SFF-8432 | 
			6Gbps 
			8.5Gbps 
			10Gbps | 
			 850nm 
			1310nm 
			1550nm 
			CWDM 
			DWDM 
			BIDI 
			Tunable 
			Copper | 
			OM3 
			OM4 
			OS1 
			OS2 | 
			120km | 
			LC | 
			Yes | 
			Commercial 
			Industrial | 
		
		
			|  XFP | 
			IEE802.3ae 
			XFP MSA | 
			6Gbps 
			8.5Gbps 
			10Gbps | 
			850nm 
			1310nm 
			1550nm 
			CWDM 
			DWDM 
			BIDI 
			Tunable 
			Copper | 
			OM3 
			OM4 
			OS1 
			OS2 | 
			120km | 
			LC | 
			Yes | 
			Commercial 
			Industrial | 
		
	
SFP VS SFP+ (SFP Plus)
SFP and SFP+ with a similar form factor dimension,hence looks like the same.
SFP optics usually support 155Mb/s,1.25Gb/s to 4.25Gb/s while SFP+ ones supports data rates up to 8.5Gb/s and 10Gb/s.
SFP is for Fast Ethernet ,Gigabit Ethernet,1x/2x/4x Fiber Channel and SDH/SONET with data rate below 2.488Gb/s applications. SFP+ for 10 Gigabit Ethernet,10G SDH/SONET applications. SFP is compliant with IEEE802.3, INF-8074 and SFF-8472 while SFP+ is compliant with the protocol of IEEE 802.3ae, SFF-8431, SFF-8432.
XFP VS SFP+ (SFP Plus)
XFP is a separate standard that also supports 10Gb/s speeds for applications of 10 Gigabit Ethernet, 10 Gbit /s Fibre Channel, Synchronous optical networking (SONET) at OC-192 rates, Synchronous optical networking STM-64, 10 Gbit /s Optical Transport Network (OTN) OTU-2, and parallel optics links.4. The primary difference between SFP+ and the slightly older XFP standard is that SFP+ without chip for clock and data recovery that makes an 
SFP+ smaller than an XFP, enabling greater port density. However, some SFP+ optics manufacturer like Fiberland have develop SFP+ with CDR that for special applications. XFP is defined by XFP Multi Source Agreement that is different with SFP+ MSA. Since SFP+ smaller dimension than XFP that provide a higher port density in switch and routers,nowadays it becomes more and more popular.
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XFP module,
XFP transceiver Which is good? First choice Fiberland!Thanks for your concern, to learn more about Fiberland, please enter Fiberland website: 
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