QSFP vs SFP+ : What's the difference?

Comparison: SFP+ vs QSFP
 

Optics Type	Standard	Data Rate	Wavelength	Fiber Type	Max Distance	Typical Connector	DOM	Operating Temperature
SFP+ (Product)	IEE802.3ae SFF-8431 SFF-8432	6Gbps 8.5Gbps 10Gbps	850nm 1310nm 1550nm CWDM DWDM BIDI Tunable Copper	OM3 OM4 OS1 OS2	120km	LC RJ-45	YES	Commercial/Industrial
QSFP+ (Product)	IEEE 802.3ba QSFP+ MSA SFF-8436 SFF-8636 Infiniband 40G QDR	41.2Gbps	850nm 1310nm 832-918nm	OM3 OM4 OS1 OS2	40km	LC MTP/MPO	YES	Commercial/Industrial

SFP+ vs QSFP+
The primary difference between QSFP and SFP is the quad form. QSFP+ is an evolution of QSFP to support four 10 Gbit/s channels carrying 10-Gigabit Ethernet, 10G Fiber Channel, or InfiniBand, which allows for 4X10G cables and stackable networking designs that achieve better throughput. QSFP+ can replace 4 standard SFP+ transceivers, resulting in greater port density and overall system cost savings over SFP+.
 
 

What do sfp+and QSFP represent respectively?

 

What is an SFP+ Transceiver?

Compared to SFP transceivers, SFP+ transceivers are a more advanced version of the technology. SFP+ transceivers are most typically offered at 8Gbps, 10Gbps, or 16Gbps. They have the exact dimensions of SFPs, making it simple to integrate them into existing infrastructure. SFP+ transceiver is one of the most popular data center cabling applications.
Depending on the application, the SFP+ transceiver can be divided into five broad categories: Dual Fiber SFP+, BiDi SFP+, Copper SFP+, CWDM SFP+, and DWDM SFP+.
“SFP Plus”, or SFP+, are speed enhanced variations of the predecessor SFP form factor. SFP+ electrical and mechanical specifications were developed in 2006 under SFF Committee documents SFF-8431 and SFF-8432, which also defined the 10Gb/s Ethernet non-retimed high speed electrical interface. SFP+ is targeted at enabling 8Gb/s to 16Gb/s applications, such as 10Gb/s Ethernet as well as 8GFC and 16GFC Fibre Channel.
 

What is a QSFP+ Transceiver?

QSFP+, often known as QSFP, is an abbreviation for quad (4-channel) small form-factor pluggable. QSFP+ optics is yet another tiny, hot-pluggable transceiver used in data transmission. Compared to SFP+, QSFP+ supports 4x10G or 4x14G SFP+ data rates to enable increased bandwidth capabilities. It provides several data rate options for Ethernet, Fibre Channel, InfiniBand, and SONET/SDH technologies.
 
Definition and Application of QSFPQSFP also called QSFP+, it stands for Quad (4-channel) Small Form-factor Pluggable Optics Transceiver. It is a compact, hot-pluggable fiber optical transceiver used for 40 Gigabit Ethernet (40GbE) data communications applications. It’s designed according to QSFP+ Multi-source agreement and IEEE802.3ab, they are usually for the application of Data center, 40G Ethernet, Infiniband, and other communications standards.
It interfaces a network device (switch, router, media converter or similar device) to a fiber optic or copper cable. It is an industry standard format defined by the Small Form Factor Committee (SFF-8436, Rev 3.4, Nov. 12, 2009—Specification for QSFP+ Copper and The CFP MSA was formally launched at OFC/NFOEC 2009 in March by founding members Finisar, Opnext, and Sumitomo/ ExceLight. The format specification is evolving to enable higher data rates; as of May 2013, the highest supported rate is 4x28Gbps (112Gbps) defined in the SFF-8665 document (commonly known as QSFP28) which will support 100GE.
The QSFP MSA specification supports Ethernet, Fibre Channel, InfiniBand and SONET/SDH standards with different data rate options. The QSFP Multi Source Agreement (MSA) document specifies a QSFP optic transceiver mechanical form factor with the latching mechanism, host-board electrical edge connector and cage. QSFP+ optic transceivers are designed to support Serial Attached SCSI, 40G Ethernet, 20G/40G Infiniband, and other fiber optic communications standards as well as copper cable media. The QSFP optic modules highly increase the port-density by 4x compared to SFP+ optic modules.
 
 

Describe a QSFP port.

Another kind of tiny, hot-swappable transceiver is the QSFP (quad small form factor pluggable) device. With various data rate choices, it supports the Ethernet, Fibre Channel, InfiniBand, and SONET/SDH technologies. Several distinct types of QSFP modules are frequently available, including 4x28Gbps QSFP28, 4x28Gbps QSFP28, and 4x1Gbps cisco QSFP.
The most current variants, QSFP+ and QSFP28, offer a wide range of 40Gbps and 100Gbps applications. Four transmit and four receive channels are included in QSFP+ and QSFP28 modules. SFF-8436 is the foundation for the QSFP standards.

How Should I Pick an SFP Transceiver?

In addition to SFP vs. SFP+ vs. QSFP, you must also take the application into account. Depending on their intended usage, SFP transceivers come in a variety of kinds, such as single-mode vs. multimode SFP. Multimode SFPs are compatible with multimode fiber, whereas single-mode SFP transceivers only operate with single-mode fiber. There are also long-reach WDM SFP transceivers for multiplexing, simplex SFPs for use with a single fiber, video SFPs for high-definition video transmission, and PON SFP transceivers for use with fiber-based access networks. SFPs come with or without expanded diagnostics capabilities and in commercial and extended operating temperature ranges.

Cable QSFP+ to SFP+

A QSFP+ transceiver and four SFP+ transceivers make up a QSFP+ to SFP+ cable, as seen in the following diagram. The switch’s QSFP+ access port accepts a direct connection from the QSFP+ transceiver. The cables support simultaneous bidirectional communication on four connections using high-performance integrated duplex serial data lines. The Cisco SFP connections can handle up to 10 Gbps of data per link. There are two types of QSFP+ cable: passive and active. The transmission distance of passive QSFP+ cable is often less than that of active QSFP+ cable since there is no signal amplification integrated into the cable assembly.