The local area network is completely protected against lightning attacks.

High efficiency and security are one of the main theme of LAN device operation. However, when talking about LAN security, most people will focus on network anti-virus and network attack prevention, few consider that lightning strikes or inductive lightning strikes can pose a fatal security threat to lan devices. Today, with the increasing number of high-rise buildings, local area network devices are more and more likely to suffer from lightning strikes. If we do not take lightning protection measures in a timely manner, it is easy to make network devices unavailable, in severe cases, network equipment can be damaged or burned down, which can cause economic losses to us. In order to keep LAN equipment away from lightning attacks and improve the stability of network equipment, we must pay great attention to and actively respond to the LAN lightning protection problem. Next, I would like to give some comments on how to avoid lightning attacks on LAN devices. I hope you can criticize and correct them.
What attacks does lightning bring to the lan?

Because most of the network devices used in Lan are precision electronic devices, these electronic devices have limited ability to resist current, voltage, or electromagnetic pulse, in addition, most LAN devices need to work continuously. In this case, many important network devices must be in the starting status 24 hours a day, so long as the thunderstorm is approaching, lan devices may be attacked by lightning. If lightning occurs not far from the LAN, the strong current generated by lightning may intrude into the LAN system through the communication cables or power cables in and out of the LAN, once the LAN device does not take any lightning protection measures, these devices will certainly be unable to withstand up to tens of thousands of volts of high voltage or tens of thousands of amps of high current, in this case, the LAN device may experience incorrect operations, data loss, or crashes. In serious cases, computer systems or other network devices may be burned down, even if some network devices are not damaged by powerful lightning currents or voltages, some of their internal electrical properties will be affected to a certain extent, which will easily affect the stability of the overall LAN performance.

The reason why lightning brings disasters to the LAN system is not only related to the attack and destructive nature of lightning, it is also related to the failure of the network management personnel to correctly install the lightning protection equipment or the unqualified quality of the selected lightning protection equipment. Judging from the events of many network devices being attacked by lightning, some organizations or network staff have insufficient awareness of the importance of Lightning Protection in the LAN system. As long as the equipment is out of service, it cannot prevent lightning strikes, security risks are prominent. Some people think that their network equipment will not be attacked by lightning in the building. In particular, with the gradual popularization of Internet networks, the desire for Internet access from various departments or departments of the same unit is getting stronger and stronger, and network administrators can arrange network cables freely, because no lightning protection device is installed in the network connection line, the outdoor network connection line is almost changed to a lightning generator, which leads to frequent lightning strikes.

TIPS: Lightning Current, in addition to communication cables or power cables, can cause direct attacks to lan devices. In addition, lightning current can also cause indirect damage to LAN systems, for example, when the lightning current flows along the leader of the LAN building to the ground, a powerful electromagnetic field is generated around the leader. If the LAN equipment is close to the leader, then the network device will automatically generate a powerful lightning-induced current, which will easily damage the network device. In addition, when lightning currents leak to the ground through lightning protection leads, a high ground network potential is generated. These high potentials may intrude into the local area network device through the Local Area Network ground, thus causing damage to the network device.

4. Regular overhaul of Lightning Protection Facilities
Do not think that after the lightning protection facilities are installed, the LAN equipment will not be attacked by lightning. We should always establish a sense of lightning protection. When the annual thunderstorm season is approaching, carefully organize professional personnel to regularly repair and maintain the lightning protection equipment of the LAN system, and check whether the lightning protection facilities are aging or ineffective, and whether they are damaged or damaged by humans. If the lightning protection facilities are found to be unable to work properly, replace and install new devices in time to eliminate potential lightning hazards.

5. Correct grounding

Because lightning current or lightning voltage leak to the ground, the grounding effect directly affects the lightning protection effect, therefore, proper grounding of LAN equipment is a key link to prevent lightning strikes. Generally, each network device in the LAN should not be grounded independently. Otherwise, the grounding system of each device may generate a potential difference. When the difference reaches a certain value, it will also cause damage to the network device; in order to avoid potential difference between different grounding systems, it is best to share all the devices in the LAN with the same grounding system, so as to ensure that the Grounding Potential between various network devices is equal. In addition, the shield layer at both ends of the twisted pair line used in the LAN can be connected with the metal housing of the network equipment, and separate building grounding (of course, the building itself must meet the grounding requirements ).

6. Establish a strong awareness of Lightning Protection

Only by firmly setting up the awareness of lightning protection can we cultivate good operation habits in network management and maintenance work. For example, if a thunderstorm is coming soon, you should cut off the physical connection between the outdoor connection cable and the indoor network device in advance. It is recommended that you do not operate the computer during the occurrence of lightning, cut off all the power supplies in the LAN data center. Do not place important network devices close to the walls or lightning wires.

The above various lightning prevention measures should not be used independently, but should be used for LAN systems with multiple levels of lightning protection measures. Only in this way can the safe operation of LAN equipment be ensured, minimize the loss and harm caused by lightning current or voltage to the network system.