All you want to know about 100G optical module is here

In order to adapt to the scale deployment of AI, deep learning, big data computing and other businesses, the data center network has begun to move towards 100G or even higher. During the construction of 100G network, a large number of 100G optical modules need to be used, and the cost accounts for a high proportion of the total construction cost. How should we choose a more cost-effective 100G optical module?

What is a 100G optical module?

As the name implies, the 100G optical module means that the propagation rate reaches 100G. However, in order to meet 100G interconnection scenarios at different distances, the standardization organizations of the major optical modules have formulated different standards for 100G optical modules. Now we will explain the application of 100G optical modules of different standards.

1、 Application of 100G optical module

1. Short distance transmission

100G optical module standards for short distance transmission are mainly 100GBASE SR10 and 100GBASE SR4. Among them, the 100GBASE - SR10 standard was the first to be used, because the switch ASIC chip electrical interface at that time could only support 10G at most. Its principle was to use 10 x 10Gbps parallel channels to achieve 100Gbps point-to-point transmission.

However, with the increase of the switch ASIC chip's electrical interface speed from 10Gpbs to 25Gbps, and the electrical interface standard from CAUI-10 (10 channels x 10Gbps) to CAUI-4 (4 channels x 25Gbps), the 100GBASE SR4 optical module standard was born.

100GBASE - SR4 requires fewer optical modules than 100GBASE - SR10, making the optical module smaller in size, lower in cost and lower in power consumption.

Due to the reduction of the optical module size, the 100G ports of the switch interface board can be made more dense. Based on the above advantages, 100GBASE-SR4 has become the mainstream 100G short-range optical module standard. The 100G QSFP28-SR4 optical module is commonly used in this standard. It is a parallel 100G optical module that provides four independent sending and receiving channels. Each channel can operate at 25Gbps at 70/100m of OM3/OM4 MMF. The overall data rate is 100Gbps, which is widely used in data centers.

2. Medium distance transmission

100G optical module standards for medium distance transmission are mainly 100GBASE-PSM4 and 100GBASE-LR4. The transmission distance of PSM 4 is within 500M, and the transmission distance of 100GBASE-LR4 is within 10KM. The main optical modules are 100G QSFP28 PSM4 optical module and 100G QSFP28 LR4 optical module.

100G QSFP28 PSM4 optical module is a high-speed and low-power product, which is specially used for optical interconnection in data communication applications. It conforms to the PSM4 MSA optical interface specification, has a hot pluggable QSFP shape, built-in digital diagnostic function, and a total of four independent full duplex channels. Each channel can reach a data rate of 25.78Gbps and a wavelength of 1310nm. It is mainly used in 100G Ethernet.

The working principle of 100G QSFP28 LR4 optical module is to multiplex 1270nm, 1290nm, 1310nm and 1330nm to a single mode optical fiber for signal transmission through rough wavelength division multiplexing technology. The transmission rate of 100G QSFP28 LR4 optical module is 103.1Gbp, and the transmission distance is 10KM. It is mainly used in computing, high-frequency trading and other fields.

3. Long distance transmission

The 100G optical module standard for long-distance transmission is mainly 100GBASE-ER4. Its representative optical modules are 100G QSFP28-ER4, whose maximum transmission distance can reach 40km. Its principle is to convert four 25Gbps electrical signals into four LAN WDM optical signals, and then use MUX or WDM to multiplex them into a single channel to achieve 100G optical signal transmission. At the receiving end, the module uses DEMUX to demultiplex 100G optical input into 4-channel LAN WDM optical signal, and then converts it into 4-channel electrical signal and then outputs the channel.

Deep Analysis of the Categories and Applications of Ethernet Switches

As one of the most widely used network equipment, ethernet switch plays a more and more important role in data communication. its development is of great significance to manufacturing industry and communication industry.

Ethernet switches, from the earliest Layer 2 switches to the current Layer 3 switches and multi service switches, have more and more functions; Switches play more and more roles, including routers, firewalls, wireless AC, etc.