Some of the main causes of network failure are as follows.
1. hacking attacks from external INTEL networks (e.g. Ddos attacks, etc.).
2. Attacks from intranet “insiders”.
3. an attack from a worm in the intranet.
4. an attack from an ARP spoofing Trojan in the intranet (i.e. ARP spoofing).
5. Network failures caused by broadcast storms, etc.
Prevention and Solutions.
1. first install high-end routers, hardware firewalls and other network devices.
2. install the sniffer packet capture and analysis tool and Lanexplorer network search tool on the computer.
3、Installation of genuine OS and timely OS patch update.
4. installing anti-virus software on each computer and updating the anti-virus software in a timely manner.
5. Close some unused services and ports, do not browse unsafe websites and do not open emails from unknown sources.
6. installing a personal version of the software firewall on each computer.
7. To prevent ARP spoofing, an ARP firewall should be installed on each computer (as I have described earlier).
8. Prevent LAN loops.
LAN loops can cause intermittent LAN cramps, and the following points should be noted when using hub.
1) Do not reconnect with a network cable between two small hubs that are already connected to the switch!
2) Do not connect two ports of the same hub or switch with a network cable.
3) Do not use network cables between the cascaded hubs to connect to the parent switch again.
Here’s a little more about the “radio storm”.
What is a broadcast storm?
A data frame or packet being transmitted to each node on the local network segment (defined by the broadcast domain) is a broadcast; due to network topology design and connectivity issues, or other reasons, the broadcast is replicated in large numbers within the segment, propagating data frames and causing network performance degradation or even network collapse, which is known as a broadcast storm.
What are the causes of the broadcast storm?
There are many reasons for the formation of radio storms, and the following five are given here.
★ Network equipment reason: the switch is point-to-point forwarding, generally will not generate broadcast storms. However, when we purchase network settings, the switch purchased, usually replaced by the crooks with a smart Hub. Thus, when the network is busy, the possibility of generating a broadcast storm up will be greatly increased.
★ NIC damage: The damaged NIC keeps sending a large number of packets to the switch, generating a large number of useless packets and generating a broadcast storm. The broadcast storm caused by physical damage of NIC is more difficult to troubleshoot because the damaged NIC is usually still able to access the Internet. Generally, you can borrow Sniffer LAN management software to check the network data traffic to determine the location of the failure point.
★ Network Loop: If there are two ends of a twisted-pair cable plugged into different ports of the same switch, it will lead to a sharp drop in network performance and make it very difficult to open web pages, which will lead to broadcast storms (this is only one type of network loop, I will introduce you to other types of network loops in the Knowledge Links section below). Network loops generally arise when both ends of a physical network line are connected to a single network device at the same time.
★ Network viruses: Some of the more popular network viruses such as Funlove, Shockwave, RPC, etc. will spread through the network as soon as a machine is poisoned. The spread of network viruses will then deplete a large amount of network bandwidth, cause network congestion, and cause broadcast storms.
★ The use of hacking software: some Internet users, often using network bailiffs, network scissors and other hacking software, the internal network of the Internet cafe to attack, due to the use of these software, the network may also cause a broadcast storm.