what is network security

Network security is a set of technologies that protects the usability and integrity of a company’s infrastructure by preventing the entry or proliferation within a network of a wide variety of potential threats.  

A network security architecture is composed of tools that protect the network itself and the applications that run over it. Effective network security strategies employ multiple lines of defense that are scalable and automated. Each defensive layer enforces a set of security policies determined by the administrator

What are the key tools of network security?

A multi-layered approach to network security implements controls at numerous points within a network to provide comprehensive access control and threat control.  

• Firewall : A firewall establishes a barrier between the trusted and the untrusted areas of a network. Thus, a firewall performs access control and macro-segmentation based on IP subnets. The same firewall may also perform more granular segmentation, known as micro-segmentation. 
• Load Balancer :  A load balancer distributes load based on metrics. By implementing specific mitigation techniques, a load balancer can go beyond traditional load balancing to provide the capability to absorb certain attacks, such as a volumetric DDoS attack. 
• IDS/IPS : The classic IDS/IPS is deployed behind a firewall and provides protocol analysis and signature matching on various parts of a data packet. Protocol analysis is a compliance check against the publicly declared specification of the protocol. Signature matching prevents known attacks such as an SQL injection.  
• Sandbox :  A sandbox is similar to an IDS/IPS, except that it does not rely on signatures. A sandbox can emulate an end-system environment and determine if a malware object is trying, for example, to execute port scans.  
• NTA/NDR : NTA/NDR looks directly at traffic (or traffic records such as NetFlow) and uses machine learning algorithms and statistical techniques to evaluate anomalies and determine if a threat is present. First, NTA/NDR tries to determine a baseline. With a baseline in place, it identifies anomalies such as traffic spikes or intermittent communication.