Basic Knowlege You Have to Know About 25G Transceivers

NADDOD Edward Jan 14, 2023

With the advent of the 5G era, the demand for optical transceiver is rising rapidly. Energy saving and cost are two indispensable conditions for data centers to deploy networks. 40G optical transceiver and 100G optical transceiver are expensive and consume too much power, while the speed of 10G optical transceiver cannot meet the network demand. 25G SFP28 optical transceiver make up for the shortcomings of the first three, greatly increases the port density and reduces the network deployment cost, and the power consumption is relatively low.

Basic Knowlege You Have to Know About 25G Transceivers

25G Optical Transceiver

Brief Introduction of 25G Optical Transceiver

The 25G optical transceiver is an optical transceiver with transmission rate of 25 Gbps. It is mainly used in 25G Ethernet and 100G Ethernet (4 X 25 Gbps) and form factored as SFP28. The 25G optical transceiver is used to interconnect data center servers and switches.

The following table lists the details of the 25G Ethernet interface standards specified by the IEEE 802.3 Working Group.

Classification and Application of 25G Optical Transceiver

With the rapid development of Internet cloud computing and big data, the construction of IT infrastructure data centers is further accelerated. SFP-25G-SR optical transceiver and SFP-25G-LR optical transceiver are favored by the majority of data center users because they can provide 25G and 100G network solutions economically and efficiently. The 25G optical transceiver is classified into SFP- 25G-SR and SFP- 25G-LR. For details, see the following table.

1.SFP-25G-SR Optical Transceiver

The SFP-25G-SR optical transceiver complies with multiple standards and specifications of IEEE 802.3SFF-8472 SFF-8402 SFF-8432 and SFF-8431, its central wavelength is 850nm. Since the transmitter inside the SFP-25G-SR is a vertical cavity surface emitting laser (VCSEL), it needs to be used together with OM3/OM4 multimode fiber. It is a short-range transmission transceiver. The SFP-25G-SR has DOM function, which helps network management to monitor all aspects of the optical transceiver information in real time. It is mainly applicable to 25G Ethernet switch, router, network interface cards and storage network devices.

2.SFP-25G-LR Optical Transceiver

SFP-25G-LR optical transceiver complies with multiple standards and specifications such as IEEE 802.3, SFF-8472, SFF-8402, SFF-8432 and SFF-8431. Its central wavelength is 1310nm, and it is usually used together with single-mode optical fibers. The transmission distance can be up to 10km, which is suitable for long-distance data transmission. The SFP-25G-LR optical transceiver uses the DFB laser.

Introduction of NADDOD’s 25G SFP28 Optical Transceiver

25G SFP28 SR Optical Transceiver

The 25G SFP28 SR 100m optical transceiver is a single-channel, hot swappable optical module for 25 gigabit Ethernet and Infiniband EDR applications. It is a high-performance short-range data communication transceiver that transmits 70m on OM3 multimode fiber and 10m on OM4 multimode fiber. The transceiver is designed to use a multimode optical fiber system with wavelength of 850nm. The electrical interface uses 20 contact edge type connectors. The optical interface adopts duplex LC.

Supports hot-swappable SFP28 form factor
The maximum transmission distance is up to 70m in the multi-mode OM3 and 100m in the multi-mode OM4
850nm VCSEL laser and light detector
Both the transmitting and receiving channels have built-in CDRS
Duplex LC optical port
Single power supply 3.3V
The power consumption is less than 1W
Supports I2C communication interface and digital diagnosis function
Meet RoHS6 (lead-free)
Operating temperature: 0~70℃

25G SFP28 LR 10km Optical Transceiver

25 Gbit/s SFP28 LR 10km optical transceiver Single-channel, supports hot swappable 25 Gbps Ethernet, and InfiniBand EDR applications. It is a high performance transceiver for short range data that supports communication and interconnection applications with transmission distances up to 10 km at 25.78125 Gbps. This transceiver mainly uses 1310nm wavelength single-mode fiber. The optical interface uses duplex LC.

Hot-swappable SFP28 form factor
Supports 25Gbps data rate
Supports 10 km link
DFB laser and PIN photodetector
Both transmitter and receiver have built-in CDRS
Duplex LC
3.3V power supply
Power consumption < 1.5w
Digital diagnosis function, I2C communication interface
RoHS6 (lead-free)
Operating temperature: 0℃ + 70℃

Technical Development of 25G SFP28 Optical Transceiver

The 25G SFP28 optical module is mainly used to interconnect servers and switches in data centers. It is a new Ethernet standard with many advantages. It was proposed by IEEE 802.3 working group in July 2014, and fully revised in June 2016. The biggest advantage of 25G Ethernet technology for data centers is that it can maximize bandwidth and port density, and it can also use 25Gb/s single-channel physical layer technology to achieve 100Gb data transmission.

Features and Advantages of the 25G SFP28 Optical Transceiver

The 25G SFP28 optical transceiver offers 2.5 times the optimal input/output (I/O) performance and fiber capacity of 10G Ethernet, with higher port density, it can save operating costs by reducing the number of ToR switches and cables.

Compared with 100G optical transceiver, 25G SFP28 optical transceiver also has less loss. In addition, the 25G SFP28 optical transceiver can use two fiber channels to achieve a transmission rate of 50G. Compared with the 40G optical transceiver using four 10G Fibre channels, the 25G SFP28 optical transceiver is undoubtedly a better choice.