Difference between industrial Ethernet switch and industrial EPON

In industrial communication products, industrial Ethernet Switch and industrial EPON are two common products, each with its own characteristics. Today, EPON is simply compared in terms of protocol, industrialization degree and networking mode.
1. Protocol standardization

The use of switches has been very mature, and the standardization of their protocols has long been completed, including underlying protocols, network redundancy protocols, management protocols, network precise clock transmission protocols, etc. the products of different manufacturers have good interoperability and can realize hybrid networking.

The EPON standard was officially released in 2004, and the industrial EPON standard has only been improved in recent years, so many specific implementation details need to be standardized. For example, dynamic bandwidth DBA algorithm, ranging implementation algorithm, encryption algorithm, etc. from the current state, there are still some risks in interoperability, which will take some time.

The concept of industrial Ethernet switch has been put forward since 2000 and has experienced rapid development for more than ten years. The whole industrial chain is very mature in terms of chip and market. EMMC, high and low temperature and other industrial characteristics can be fully met. It has been widely used in markets other than distribution network.
As a relatively new technology, EPON has a short industrialization time, and is mainly concentrated in the power industry, with insufficient actual operation experience. The Optical Splitter is a passive component with high stability. However, OLT and ONU are active devices, and most of them are not as industrialized as industrial Ethernet devices.
2. Networking mode
EPON can form point to multipoint network mode through beam splitter, which is very suitable for the actual distribution of distribution network. Each ONU is connected in parallel, with strong anti multipoint failure ability. The possible disadvantage is that all business processing is concentrated on OLT, and the stability of OLT is very important. After OLT takes effect, the whole network will be paralyzed and the communication between underlying nodes will be interrupted.
Due to the insertion loss of the optical splitter, the network cannot be too long, which can not exceed 20km at most. For the capacity expansion of new nodes, the direction can be increased by replacing the optical splitter, which is very convenient.
Industrial Ethernet switches mainly adopt segmented redundancy, intersecting ring, tangent ring and other methods to improve the reliability of networking and have weak ability to resist multi-point failure. In its peer-to-peer communication mode, the failure of a single node will not have a fatal impact on the whole network. By selecting the appropriate optical module, the transmission distance can reach up to 100 km. For capacity expansion, the switch of the connected node needs to be replaced to support more optical ports, and the cost will increase.
For the two-way advantages of EPON single fiber, firstly, at present, only one Optical Fiber will not be laid during wiring, and the industrial Ethernet switch can also support single fiber transmission through the optical port of single fiber.