How to prevent Thunder in LAN

High efficiency and safety is one of the main themes of LAN equipment work, but mention LAN security, I believe most people will focus on network anti-virus, network defense attacks, and very few people will consider lightning or induction lightning can also cause a fatal security threat to LAN equipment. In the increasing number of high-rise buildings today, LAN equipment is more and more likely to be struck by lightning, if we do not take the lightning measures in time, so light will easily lead to network equipment can not work properly, serious words can damage or burn network equipment, so that we bring economic losses. In order to keep LAN equipment away from Thunder attack and improve the working stability of network equipment, we must attach great importance to and actively deal with the problem of LAN lightning protection. Below, the author of LAN equipment How to avoid lightning attacks, put forward some of their views, I hope you can criticize the Netizen.

What attacks Lightning will bring to the LAN

Since most of the network devices used in the LAN are sophisticated electronic devices, these electronic devices are very limited in their ability to resist current, voltage, or electromagnetic pulses, and most of the LAN devices need to work continuously, so that many important network devices must be powered up for 24 hours, Such a dozen to thunderstorm weather, LAN equipment may be hit by lightning. If the lightning occurs in the local area network not far from the location, then the strong current generated by lightning, may pass through the LAN communication cable or power cable, intrusion into the LAN system, once the LAN equipment did not take any lightning protection measures, Then these devices must be unable to withstand up to tens of thousands of volts of strong voltage or tens of thousands of amps of strong current, such as light will cause LAN equipment error operation, data loss or a crash phenomenon, serious words can burn computer systems or other network equipment, and even the life of the local area network staff pose a threat; Even if some network devices are not damaged by a powerful lightning current or voltage, some electrical properties within them will be affected to a certain extent as long as they suffer from lightning attacks, which can easily affect the stability of the overall performance of the LAN. (Computer science)

Thunder and lightning will bring disaster to LAN system, in addition to the attack and destructive power of lightning, but also with the network management personnel not in accordance with the provisions of the correct installation of lightning protection equipment or the selection of lightning protection equipment quality. From many network equipment by lightning attack events, some units or network staff on the LAN system to prevent the importance of awareness, lightning protection equipment for years of disrepair, simply can not play a role in the prevention of lightning, security risks are more prominent; there are some people with paralysis, luck, Think that their network equipment inside the building will not be attacked by lightning. In particular, with the gradual popularization of Internet networks, units or the same unit in various departments of the Internet desire more and more strong, network management staff at random to decorate the situation is also more common, because the network cable does not install lightning protection devices, outdoor network cable almost become a lightning fuse, Thus, lightning failure occurs frequently.

Small tip: Lightning Current in addition to through the communication cable or power cable, in addition to direct attacks on LAN devices, it is possible to indirectly damage the LAN system by inducing lightning currents, such as lightning currents that generate a strong electromagnetic field around the lightning leads as they flow to the ground along the lightning-prevention leads in the building where the LAN is located. If the LAN device is closer to the lightning-free lead, then the network equipment "body" will automatically generate a powerful lightning current, these strong currents will easily damage the network equipment; In addition, lightning current through the lightning leads to the ground leakage, will produce a very high ground net potential, These high potentials may invade the LAN equipment through the grounding line of the LAN, thereby causing damage to the network equipment.

How to carry out effective lightning protection

Since lightning attacks can cause a fatal threat to LAN devices, in the summer of thunderstorms, we should actively take effective measures to avoid the local area network equipment under lightning attacks. Because of the lightning protection of LAN equipment, not only with the local area network of various communication cables and power cable, but also with the local area network equipment quality, location, use conditions and surrounding environment, so only a variety of preventive measures multi-pronged, in order to effectively prevent lightning current damage to network equipment attacks.

1, comprehensive wiring should be strictly standardized

Perhaps many people do not understand, LAN thunder how can and integrated wiring related? In fact, the integrated wiring is the basis of lightning protection, only in the initial period of the formation of local area network, strictly in accordance with the norms and standards for wiring, strictly prohibit unauthorized wiring, in order to avoid the relatively poor shielding effect of the twisted pair becomes a lightning fuse, In order to avoid the local area network system Legacy Lightning protection, if not in accordance with the requirements of the wiring, the twisted pair or other communication cables erected in the vicinity of the window or with the lightning leads around, or directly to the communication cables exposed to outdoor air without taking any lightning protection measures, Then lightning current or lightning induced currents will easily be through these communications cables or power cables, intrusion into the LAN system, so that the LAN equipment to cause a fatal blow.

Small tip: In order to prevent the upper body, the LAN should be set up as far as possible not to decorate the cable in the outdoor, also do not close the network line to the Lightning leader; If you do need to have the network cable in the outside, the network cable can not use ordinary twisted-pair, but should use fiber cable, and cable is best not to use overhead wiring, as far as possible to bury the connection cable buried in the ground. In addition, the LAN network equipment in the computer room, but also from the angle of the lightning protection to choose a good location, the room is best in the location of multi-storey buildings in the three or four-storey, and can not be in the top floor or corner position of the building.

2. Network equipment should have lightning protection function

Because most of the equipment in the LAN needs to work continuously, this requires the quality of these devices themselves, it is best to contain the ability to prevent lightning, so as to ensure that they work in a long period of time to maintain a stable performance, if the selected equipment itself has a lightning protection function, even if we did not take other measures to prevent lightning, Lightning currents also do not cause fatal damage to these devices. In addition, once the network equipment of their own quality, you can ensure that they have enough resistance to external interference, so as to ensure the performance of local area network stability.

3, the correct installation of lightning protection equipment

Using lightning protection equipment to protect the local area network is one of the most direct and effective methods.

First, the LAN room where the building should be installed lightning rods, which can effectively avoid the LAN equipment directly affected by lightning current attack; At present, many new buildings have been installed on the top of the lightning rod, do not need our network management personnel to consider separately.

Secondly, the communication cable from the outside to connect with the network equipment inside the LAN, it is best to install the rj10m/100m signal Lightning protection device between the communication cable and network equipment, so that the lightning current can be avoided by the communication cable damage to the LAN equipment connected with it.

Third, now many LANs are no longer an isolated network, it is often through broadband optical fiber, 5 of unshielded twisted-pair or telephone lines and other communication media and other networks to connect and exchange to meet the needs of people exchanging information, at this time we need to be in the LAN out of the home line to install a special signal arrester to ensure that the local area network switch , routers, hubs and other network equipment are not affected by lightning strike current; In some very important network devices, such as the core servers in the LAN, it is best to use multi-level lightning protection measures to achieve a complete limit of lightning overvoltage, discharge lightning strong current purposes, so as to protect the LAN core equipment security.

Four, in the LAN room or network equipment in a more centralized location, should be in the general power supply or distribution counters installed professional power Lightning, through the device can be invaded to the local area network system lightning instantaneous voltage quickly into the form of electric current and through the ground to vent to the surface, And the lightning voltage quickly reduced to the LAN equipment can withstand the degree.

Tips: In order to prevent professional lightning protection equipment because of their own quality is not perfect for users to bring losses, in the selection of lightning protection equipment, we must check whether there is a "sales license" mark on the device shell, if there is no such sign, it indicates that the lightning protection equipment may not meet the mine standards or simply unqualified, at this time don't covet cheap, Buy these defective goods back, so as to bring lightning hazards in the future. In addition, professional lightning protection devices are mostly connected in tandem to the LAN communication line, therefore, in the selection of lightning protection equipment in addition to see whether the lightning performance to meet the requirements, but also to check whether the lightning protection equipment to meet the local area network transmission bandwidth or other network indicators requirements, as long as the above requirements of the Lightning protection equipment, is the first choice for everyone.

4, regular maintenance of lightning protection facilities

Do not think that the installation of lightning protection facilities, LAN equipment will not be hit by lightning, we should always set up the awareness of lightning, in the annual thunderstorm season is approaching, seriously organize professionals regularly to the LAN system of lightning protection equipment overhaul and maintenance, check the Lightning protection facilities aging, failure, whether by man-made damage or damage , once found that the lightning protection facilities can not work correctly, should be replaced in a timely manner to install new equipment to completely eliminate the hidden dangers of lightning.

5, the correct grounding

Because lightning current or lightning voltage are all through the ground to the surface of the leak, the quality of the grounding effect directly affect the quality of lightning protection, so properly do the grounding of LAN equipment is the key to prevent lightning. Generally speaking, the network equipment in the LAN is not suitable for individual grounding, otherwise, the grounding system of each equipment will easily produce potential difference, this difference reached a certain value, but also damage to network equipment; In order to avoid the potential difference of different grounding systems, it is best to share the same grounding system for all the devices in the LAN. This ensures that the grounding potential of each network device is equal. In addition, the isolated shielded twisted-pair cables used in the local area network can be connected to each other with the metal casing of the networking equipment, and the building is grounded (of course, the building itself must meet the grounding requirements).

6, firmly establish lightning protection awareness

Only the heart firmly set up lightning awareness, will be in peacetime network management and maintenance work, training into a good lightning protection practices. For example, once the thunderstorm weather is approaching, the physical connection between the outdoor cable and the indoor network equipment should be cut off in advance; it is best not to operate the computer during the Thunder and lightning, and to cut off all the power of the LAN room;

The above measures to prevent lightning strikes, should not be isolated to use alone, but should be for the LAN system to take a multi-level lightning protection measures, the only way to ensure the safe operation of LAN equipment, to minimize the lightning current or voltage on the network system caused by the loss and harm.