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What is network security? 

Network security is the process of safeguarding a company’s networks and preventing unauthorized access or activities. The goal of network security is to protect network data and infrastructure from outside threats. In today’s hyper-connected world, security presents a greater challenge as more business applications move to public clouds. This trend requires applications to be virtualized and distributed across many locations, some of which are outside the physical control of IT security teams. Effective strategies have evolved beyond simple firewalls and high-level network segmentation to make security intrinsic to every aspect of a network, through multiple lines of defense and solutions that are scalable and automated.



Network security definition 

Network security is the set of strategies, processes and technologies designed to protect a company’s network from unauthorized access and harm. Typical threats to network data and infrastructure include hackers, malware and viruses—all of which may seek to access, modify or damage a network. A key priority of IT network security is to control access and prevent these threats from entering and moving throughout a network. 



How does network security works? 

Multiple lines of defense protect a network at its perimeter as well as within: 

  • Access controls are the first line of defense. This includes policies and controls that manage access to a network by authorized users, but also by devices and data. 
  • Firewalls, which can be either hardware or software, are another primary line of defense. They separate the network from other untrusted networks, such as the Internet. Firewalls monitor and control which traffic can enter or leave the network. 
  • Intrusion detection and intrusion prevention systems are used to analyze network traffic to identify and respond to threats on the network. 
  • Application security is an important subset of network security that involves protecting web applications and software used by a business, since these applications often have vulnerabilities.

A range of other strategies and technologies are used to maintain security across data centers, public and private clouds and more. 



What are the essential components of network security?

For a truly secure network, IT managers must consider many different aspects of network security. 

  • First, there is access control—who gets access to which parts of the network. Effective access control means preventing unauthorized users from accessing the network and any devices that connect to the network. Any cloud-based network needs security measures that extend to data passing between a data center or cloud in a hybrid cloud environment, or multiple public clouds in a multi-cloud environment.

  • Once a network’s access has been secured, organizations must implement effective user authentication measures. Multi-factor authentication is the most secure way to authenticate users. Employees, especially those who authenticate with just a username and password, can be a gaping security hole.

  • Employee education, especially about phishing and good password hygiene practices, is also critical to any organization’s network security.

  • Vulnerability testing is another important component of network security. Once all of the other practices have been put in place, they must be tested for vulnerabilities—often, as the threat landscape is continually evolving.

  • Finally, the network must be continually monitored for security threats.



What types of threats does network security prevent? 

Cyber criminals are continually coming up with new ways to access corporate networks, so it is important to stay aware of new cyber threat trends and ways to prevent them as well as staying on top of software updates and patches. Certain types of threats have been growing in popularity over the past few years, and there are many different network security tactics to prevent them: 

  • Ransomware has been one particularly lucrative type of attack, because many businesses simply cannot afford the down time. Backing up data off the network can render ransomware attacks ineffective. 
  • Botnets and Distributed Denial of Service attacks can be prevented by monitoring the network for malware and suspicious software. 
  • Phishing and Trojan horse attacks can be countered with employee education.



What are the types of network security?

There are three types of network security measures: threat prevention, detection and response. Different security products or tools address each of these aspects. Whichever network security software or hardware an organization uses, IT managers must stay vigilant with security patches and updates, as the cyber threat landscape evolves continuously. 

Network access control or NAC is the most basic aspect of network security. Network access control is the practice of restricting network access to only those devices that are authorized and compliant with security policies. With NAC, only devices and applications that have the required security patches and anti-intrusion software are allowed to connect to the network. Network operators define the security policies and endpoint security requirements to allow network access. Restricting network access applies to wireless networks as well. When using a Wi-Fi network, a network security key (Wi-Fi password) should be required to access it. Network security keys require the same best practices as user passwords.

Network securityfirewalls are one way that network administrators can prevent cyber criminals from gaining access to private networks. Firewalls can stop criminals from logging into a private network, but not all firewalls offer comprehensive anti-virus protection at the application level. For that, you need application security.

Application security is the process of developing, adding and testing security features within applications to prevent unauthorized access and modification. Developers can build security measures directly into application software, strictly defining which activities are allowed and which are prohibited.

Micro-segmentation can protect workloads that move among different cloud environments and require a specialized type of network security. Micro-segmentation is a network security technique where security architects use network virtualization to divide a data center into distinct security segments down to the individual workload level, and then define security controls for each segment. While micro-segmentation does not prevent malware from entering an environment, it does prevent it from migrating from server to server within the environment.

Speedy detection of an intrusion can help to contain an attack and minimize damage before it spreads across a network. Intrusion Detection Systems (IDS) and Intrusion Prevention Systems (IPS) scan the network for anomalies so that they can detect an intrusion while it is happening, or after the fact. Artificial Intelligence (AI) can automate and increase the effectiveness of intrusion detection.

Response is the last category of security measures, to be used only when other measures have failed. IT managers may choose to respond to a threat in a number of different ways, from simply notifying affected users to upgrading security protection to destroying a compromised system. Network engineers can sometimes trace the damage back to an attacker. 


Related Topics
Data Center Security
Application Security
Perimeter Firewall
Network Infrastructure Security
Cloud Security
Enterprise Security
Hybrid Cloud Security


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