IP Blacklisting Guide[/caption]
IP blacklisting is a method that is used to filter out malicious IP addresses from getting access to your network. IP blacklists include ranges of IP addresses that you wish to block. These lists can be used in combination with intrusion prevention systems, firewalls, and other tools that are used to filter traffic. Making and applying blacklists let you filter out illegitimate or malicious traffic as per policies or via the manual addition of IP addresses.
Some Challenges With IP Blacklisting
Even though blacklisting can be a great way to prevent some IP addresses from gaining access to your network, it might not be a foolproof method. The reason is that attackers have come up with many different ways to get around blacklisting. Some of these are:
Changing IP Addresses
Many attackers change their IP addresses periodically to avoid being put on blacklists. These attackers can have a range of IP addresses that they can use, which enables them to change IP addresses when they find that one is blocked. Changing the IP addresses periodically can also make it difficult to track attackers, which can help avoid the risk of prosecution.
Botnets
Many cybercriminals operate botnets which can include millions of IoT devices or end-user devices. These devices will be compromised by the attackers and they will take control of these devices. Attackers may also rent a botnet service on the dark web. Due to the massive size and increased availability of botnets, many of the attacks will be done using a large number of IP addresses, which can change constantly as devices leave and join the botnet. IP blacklisting can be an ineffective method to avoid this attack.
IP Spoofing
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Inaccurate IP Detection [/caption]
In the case of network layer attacks, attackers can make use of IP spoofing to make it appear that they are connecting through a different IP address. This will let the attackers bypass blacklisting while keeping their identity a secret.
Inaccurate IP Detection
This is another challenge that you will face when you have many people using the same IP address. When the IP addresses are dynamically assigned, you will not have a way to know the end-user that is currently using an IP address.
Shared above are some of the important things that you should know about IP blacklisting. It will be beneficial for you to understand these things while planning IPv4 rent or looking to sell IPv4 addresses.