Network security is the field of cybersecurity focused on protecting computer networks from cyber threats¹. It has three main goals:

1. Prevent unauthorized access to network resources.
2. Detect and stop cyberattacks and security breaches in progress.
3. Ensure that authorized users have secure access to the network resources they need, when they need them.

As networks grow in size and complexity, so does the risk of cyberattack. For example, according to IBM’s Cost of a Data Breach 2022 report, 83 percent of organizations surveyed experienced more than one data breach. These attacks were expensive: The global average cost of a data breach is USD 4.35 million, and the average cost in the United States is more than twice that amount, USD 9.44 million.

Network security safeguards the integrity of network infrastructure, resources and traffic to thwart these attacks and minimize their financial and operational impact. Network security systems work at two levels: at the perimeter and inside the network. At the perimeter, security controls try to stop cyberthreats from entering the network. But network attackers sometimes break through, so IT security teams also put controls around the resources inside the network, like laptops and data.

To build network security systems, security teams combine several tools:

• Firewalls: A firewall is software or hardware that stops suspicious traffic from entering or leaving a network while letting legitimate traffic through.
• Network access control (NAC): NAC solutions act like gatekeepers, authenticating and authorizing users to determine who is allowed into the network and what they can do inside.

I hope this information helps! Let me know if you have any other questions.