Recently, the company has had a network problem, the ping delay is large, and the packet loss is sti

You're clearly a network protocol attack!

There is currently a large number of cyber attacks and spoofing within the local area network. The main reasons for network inaccessibility are:

1) There is a large number of network protocol spoofing in the LAN, which will cause your host to be deceived by false information and cannot find the real device or the request cannot be responded to by the real host. For example, ARP spoofing is more familiar.

2) There are a large number of protocols and traffic attacks in the network, and network channels cause network cards or switches to be unable to transmit or exchange data. This way, your computer host will not be able to access the server. For example:

Network protocol attacks such as DDoS attacks and SYN flood attacks.

Traditional solutions: (1) ARP binding, which can alleviate the problem to a certain extent.

Note: There are now seven forms of cyber attacks or spoofing using the ARP protocol, especially the second-generation ARP that will clear your bindings. Therefore, ARP binding is a symptomatic (not necessarily effective) but not a cure.

2) There is also a rough way to redo the system and let this kind of protocol attack program be eliminated.

Note: It takes time and effort, and the problem can definitely be solved at that time. You will also be exposed to various channels and will definitely have the same problem in the future.

The solution that I have come across that can completely solve the problem of network server access is to use the Patrol Immunity Network Security Solution to install the "Terminal Immunity Driver" on each computer network card in the network The terminal MAC is taken from the physical network card instead of the system, which effectively prevents MAC cloning and counterfeiting; The terminal driver achieves two-way control, not only to defend against external threats to the machine, but more importantly, to suppress attacks from the machine. In this way, network protocol spoofing and overload attacks are directly intercepted on the network card, and you can access the server normally.

Speaking of which, I will briefly introduce the patrol immunity network security solution, in fact, there are a large number of network protocol attacks in the network of many companies, which have caused some applications (network printers can not be connected, internal server access is fast and slow, voice ** is unclear and even the computer is like a cow) can not be used normally. For these people, including me, I originally thought that it was caused by system viruses or external network attacks, and it was clear after communicating with professionals, simply put: 80% of many network problems are caused by internal network problems (network protocol attacks), and the traditional solutions (firewalls, intrusion detection systems, and anti-virus) are mainly passive prevention of external networks, system Trojan viruses and file viruses, and there is no effective solution to network protocol attacks.

The Patrol Immune Network Solution is not a separate product, but a complete set of components composed of software and hardware, intranet security protocols, and security policies. It is composed of an access module, an operation center, a terminal immunity drive, an intranet security protocol, and a security policy, which solves the attack problem from the perspective of the intranet, coping with the current trend of cyber attack complexity, diversity, and more initiation from the intranet, and more effectively solving cyber threats. Through this solution, our network can become physically strong, so that our network can defend itself and manage.

It's as simple as a reboot.

Route each port with port security.

It would be better if there was a firewall.

But according to what you say, there shouldn't be!

In addition to testing the connectivity, the ping command can also see that the target has a lot of latency.

It is normal for the packet loss rate of large ping packets to become larger, and when the network transmits large packets, it will be split into many small packets, and if one of the packets is lost, the ping is considered to have failed, so the packet loss rate will inevitably increase. Generally, there is no need to ping a large packet test.

This is in the IP protocol, you can check the relevant documentation of the IP protocol. To put it simply, if the MTU value is exceeded during the transmission of an IP packet, it will be split, the MTU value is not fixed, each network is different, and the MTU value of Ethernet that we commonly use is 1514.

Inferring that you are ping the local router, latency and packet loss should be a problem with the LAN. Directions that can be checked:

1. If you are using a network cable, please check whether the wire sequence of the twisted pair is correct (generally use the 568b standard network cable stranding method:

That is, from left to right: orange white, orange, green white, blue, blue and white, green, brown white, brown). If the line sequence is incorrect, external electromagnetic interference will affect network communication, resulting in packet loss, and devices with frequent packet loss will continue to retransmit, reducing network efficiency and high latency.

2. If you are using wireless, there should be serious interference nearby (for example, there is wifi next door and using the same frequency band), as long as the frequency band in the WLAN settings of the wireless router is set to manual, try a few more to see which band has less packet loss.

Possible causes: 1. Router; 2. The network cable from the router to the computer; 3. Computer network card.

Check the method. 1. Try to change the network cable, if it is normal after changing. It's a matter of line;

2. Find a laptop to try it, if it is normal after changing. It's a problem with the computer network card;

3. The line and the computer have been replaced, and it is not normal. The only way to do that is to change the router.

It's all plugged in the network cable or what's going on,If it's wireless, there may be wireless signal interference,If there are other wifi around,It is recommended to enter and set the channel,Generally, the default channel is 6 or 11,It seems to be 1-12。 You say the channel will revert back to its original state?

Channel 3 interferes with channel 1 6, channel 9 interferes with channel 6 13, etc., so to ensure the stable operation of multiple wireless networks in the same coverage area, it is recommended to use (or 13) these three channels. For example, in the office there are three Wi-Fi, in order to avoid drying.

scrambling and overlapping, these three channels should be used sequentially.

I don't know if there is a switch in your LAN, if so, see if the network cable connection between the route to the switch is reliable, whether the network cable is aging, worn, and whether the crystal head is standardized, you can consider reproducing a network cable.

You are ping the router has packet loss, but ping other computers do not, and there is also a possibility that one of the computers in your LAN has installed P2P software, or similar software. This software can monitor all hosts in the network, control the traffic, let you not go to the network, or drop the connection during the interruption time, and even control your QQ, and then QQ is up and down. It is recommended that you enable a firewall and install anti-ARP software.

Knowledge and ability are limited, hope it helps you

Possible causes:

1. The wireless network card of the notebook is not installed with a driver or the driver is incorrect;

2. The IP setting of the notebook is incorrect;

Solution: 1. Right-click "My Computer" - Device Manager, and in the window on the right, check whether the wireless network card is installed.

2. If the driver is incorrect, you can uninstall it and reinstall it.

3. Go to "Network Connection" to check the IP settings of the wireless network.

1) Right-click on "Network" -- Properties -- Change adapter settings. Once entered, right-click on "Wi-Fi" and click on Properties.

2) The "Wireless Network Properties" option pops up, double-click "Internet Protocol Version 6" on the page that appears, and check "Automatically get IPv6 address".

4. If the above methods still cannot connect to the network, please check whether the connection between the router and the cat is normal.

There are two scenarios that determine the delay in ping test results:

1) Is the CPU of that machine very busy, can it handle your requests in time, and if it can't take care of it, it will lose packets. Recorders along the way will also lose packets because they can't take care of it.

2) Network transmission delay, the farther the path, the greater the delay.

In the same LAN, other computers do not lose packets without delay, while the router connected to the local area loses packets and delays, it is likely that the router is busy or has other problems such as its own configuration or failure.

Is it that the router has done a rate limit on this IP, if it is to turn off the rate limit, try it!