sfp+ vs sfp28 : What's the difference?

Recognizing the difference between SFP+ and SFP28 Transceiver

SFP+ is commonly used for 10 Gbps networking applications, while SFP28 Transceiver is used for 25 Gbps applications. The main difference between the two is their data rate capability, with SFP+ supporting up to 10.3 Gbps and SFP28 supporting up to 25 Gbps. Additionally, SFP28 transceivers are typically smaller in size compared to SFP+ transceivers. Both SFP+ and SFP28 transceivers are designed to be hot-swappable, allowing them to be easily inserted and removed from a system without disrupting the network. However, the physical and electrical interfaces for SFP+ and SFP28 transceivers are not the same, so they are not interchangeable. It is important to use the correct transceiver type for the intended application.  
SFP+ and SFP28 are both small form-factor pluggable transceivers, but they cater to different data rates and applications. Here are the key differences between them:
1.Data Rate:
· SFP+: Primarily designed for 10 Gbps, used mainly for 10 Gigabit Ethernet applications.
· SFP28: Specifically designed for 25 Gbps, making it suitable for 25 Gigabit Ethernet applications. The "28" in SFP28 refers to its maximum data rate capability of 28 Gbps, though for Ethernet applications it's typically run at 25 Gbps.
2.Form Factor:
· Both maintain the same compact physical form factor, making SFP28 backward compatible with SFP+ ports. That means you can insert an SFP+ module into an SFP28 port (and it will run at 10Gbps), but you can't exploit the full potential of an SFP28 module in an SFP+ port.
3.Applications:
· SFP+: 10 Gigabit Ethernet, 8G and 16G Fibre Channel, etc.
· SFP28: Primarily 25 Gigabit Ethernet, but can also be used for other high-speed applications, such as 32G Fibre Channel.
4.Power Consumption:
· SFP28 is designed with higher performance levels but also with considerations for energy efficiency. It generally has improved power efficiency compared to SFP+.
5.Cables and Distance:
· Both SFP+ and SFP28 support direct attach copper (DAC) cables and active optical cables (AOC). However, the lengths and types of fiber supported might differ based on the specific use-case and data rate.
6.Backward Compatibility:
· As mentioned, SFP28 ports are backward compatible with SFP+ modules. However, an SFP28 module will not run at 25Gbps in an SFP+ port, given the latter's limitation to 10Gbps.
7.Market Adoption:
· SFP+ has been widely adopted in data centers for 10G applications.
· SFP28 is seeing increasing adoption, especially in modern data centers looking to upgrade their infrastructure to handle more substantial bandwidth demands but aren't yet moving to 100G.
In summary, while SFP+ and SFP28 might look identical from the outside, their primary distinction lies in the data rates they support and their associated applications. When planning a network infrastructure, it's essential to choose the appropriate transceiver based on the specific needs and future-proofing considerations.
 
 
 
 

What do SFP+and SFP28 mean respectively?

 

What is SFP+

SFP+ (Small Form-factor Pluggable Plus) is an enhanced version of the standard SFP (Small Form-factor Pluggable) transceiver. While the SFP+ and SFP form factors are the same, SFP+ is designed to handle data rates up to 10 Gbps, making it suitable for 10 Gigabit Ethernet applications.
Here are some key points about SFP+:
1.Data Rate: SFP+ supports data rates up to 10 Gbps, making it ten times faster than the standard SFP transceivers that support 1 Gbps.
2.Form Factor: Even though it supports higher data rates, the SFP+ maintains the same compact form factor as the SFP.
3.Applications: Apart from 10 Gigabit Ethernet, SFP+ modules are also used in other applications including 8G Fibre Channel, 10G Fibre Channel over Ethernet (FCoE), and high-speed storage networking.
4.Types: SFP+ modules are available in various types to cater to different networking requirements. These can be based on different distances they cover, such as SR (Short Range), LR (Long Range), and ER (Extended Range), as well as the type of fiber (single-mode or multi-mode).
5.Direct Attach Copper (DAC): SFP+ interfaces also support direct-attach copper cables, which are passive or active copper cables with SFP+ connectors on each end. They're used for short-range connections and can be more cost-effective than fiber optic cables for short distances.
6.Power Consumption: SFP+ modules generally consume less power than older 10G modules like XENPAK, XFP, or X2, making them a more energy-efficient option for 10G connectivity.
7.Backward Compatibility: While an SFP module can fit into an SFP+ port, it will only function at the 1 Gbps rate. Conversely, an SFP+ module won't fit into an SFP port because the higher speed is not supported by the SFP port.
The introduction and widespread adoption of SFP+ have played a significant role in enabling cost-effective, high-speed network connections in both data centers and enterprise environments.
 
 

What is SFP28?

SFP28 is an enhanced version of the SFP+ transceiver designed specifically for 25Gbps data rate applications. The "28" in SFP28 refers to the electrical interface, which can handle up to 28Gbps, but it's typically limited to 25Gbps when used for Ethernet applications.
Here are the main points about SFP28:
1.Data Rate: SFP28 supports data rates of 25 Gbps, which fills the gap between 10 Gbps (SFP+) and 100 Gbps (QSFP28).
2.Form Factor: SFP28 maintains the same compact form factor as the SFP and SFP+.
3.Applications: SFP28 is primarily used for 25 Gigabit Ethernet, but it can also be used for other applications such as 32G Fibre Channel.
4.Types: Like other optical transceivers, SFP28 modules come in various types based on distance and the type of fiber (single-mode or multi-mode), such as SR (Short Range) and LR (Long Range).
5.Direct Attach Cables (DAC): SFP28 also supports direct-attach copper cables, similar to SFP+. These are passive or active copper cables with SFP28 connectors on each end and are typically used for short-range connections.
6.Low Power Consumption: SFP28 modules are designed for energy efficiency, which is critical for large-scale data centers where power consumption can significantly impact operational costs.
7.Backward Compatibility: SFP28 ports can accept SFP and SFP+ modules, making them compatible with 1G and 10G network equipment. However, when using an SFP or SFP+ module in an SFP28 port, the speed will be limited to the module's respective rate (1G or 10G).
The emergence of SFP28 is primarily driven by the increasing demand for higher data rates in data centers, especially with the rapid growth of cloud services and big data applications. It offers a cost-effective upgrade path from 10G to 25G before potentially moving to 50G or 100G.
 

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Is SFP28 compatible with SFP+?

Is SFP28 compatible with SFP+? Can SFP28 run at 10gb speeds? Can you plug SFP+ into SFP28 ports on my switch? These are some of the questions we hear from customers quite often. SFP28 transceivers are nothing new in the market, but somehow we feel that there is quite a lot of uncertainty on different application aspects between these different (but in real life almost identical) form factors – SFP+ and SFP28. In this article we will try to answer all common questions on 10/25Gbe SFP28 cross-compatibility.

SFP28 SFP+ Compatibility

The most commonly asked question on SFP28 SFP+ compatibility is - Is SFP28 compatible with SFP+? Generally speaking, the short answer is yes. SFP optics work in SFP+ ports, but not vice versa. Understanding this point, review the relationships between SFP28 vs SFP+. SFP28 (small form-factor pluggable 28) is the enhanced version of SFP+ because it upgrades data rates while inheriting the same package type as SFP+. SFP28 is designed for 25Gb/s data rate transmission, yet it has backward compatibility with SFP+. For example, if plugging an SFP+ module into the switch SFP28 port, the SFP+ module will work well but the max transmission speed will auto-negotiate down to 10Gb/s.

QSFP28 QSFP+ Compatibility

Now we step into the high-speed era. Is QSFP28 compatible with QSFP+? Through the previous knowledge, you may already have the answer yourself. Let us go over the previous to find the answer. In most situations, SFP optics can be plugged into SFP+ ports while SFP+ optics cannot be plugged into SFP ports. Similarly, QSFP+ optics works in QSFP28 ports but QSFP28 optics cannot work in QSFP+ ports. Let's go back to the reason behind it. The size of the 100G QSFP28 optical module and QSFP+ module is identical. The former also has four parallel data channels, but the transmission rate of each channel has been increased from 10 Gbit/s to 25 Gbit/s, thus reaching a transmission rate of 100Gbps. QSFP28 supports not only full speed 1x 100GbE, but also 4x 10GbE and 4x 25GbE. Therefore it is feasible to plug QSFP+ optics into QSFP28 ports to run at 40Gbps.