Within a computer system, there are internal networks and external networks such as the internet. The internal system is always trusted because only the user has access to this network. However, the internet can be malicious. Several types of malware and cyber hacking codes can infect networks and dramatically damage them instantaneously. As a result, firewall network security features diverse types of methods to combat damaging malware. The method for intrusion prevention depends on the type of firewall in effect and the predicted dangers.
To know more: need of firewall in network security
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