What is Network Segmentation?

Network segmentation is a network security technique that divides a network into littler, particular sub-networks that empower network teams to compartmentalize the sub-networks and convey unique security controls and services to each sub-network.

The process of network segmentation includes dividing a physical network into diverse logical sub-networks. Once the network has been subdivided into smaller more manageable units, controls are connected to the person, compartmentalized fragments.

How Does Network Segmentation Work?

Network segmentation security controls in place, security teams have much more influence over how traffic flows within their network. They can choose to prevent all traffic from one subnet from reaching another, or restrict it according to its type, source, destination.

Network segmentation works through the process of separating, or segmenting, a network into smaller subnets. A company’s network security team will first group, or segment, its data, applications, assets, and services according to their security requirements, before applying flexible, finely-tuned security policies and controls to each compartmentalized subnet.

The purpose is to improve network performance and security. Other terms that often mean the same thing are network segregation, network partitioning, and network isolation.

An example of how network segmentation can be used is for implementing a company’s guest WIFI network. The company’s IT team can create a subnet for guests to log into that provides them with internet access while isolating them from the network’s critical data and applications. This keeps the guest’s devices away from finance and HR servers, for example, which contain sensitive data and needn’t communicate with external traffic.  

Types of Network Segmentation:

There are two types of network segmentation.

• Physical Segmentation:

Physical Network Segmentation involves rearchitecting a network into subnets through devices such as firewalls, switches and routers. This physically changes the network topology with traffic rerouted to different segments of the network through the additional devices.

• Logical Segmentation:

Logical Segmentation creates subnets using one of two primary methods: virtual local area networks (VLANs) or network addressing schemes. VLAN-based approaches are fairly straightforward to implement because the VLAN tags automatically route traffic to the appropriate subnet. Network addressing schemes are equally effective but require more detailed understanding of networking theory.

Logical Segmentation is more complicated to implement than physical segmentation, it’s more flexible and cost-effective as it doesn’t require any physical changes to the network’s topology.

Benefits of Network Segmentation:

Network Segmentation can help organizations make security, performance, and compliance improvements with greater efficiency. The most significant include benefits the following:

• Stronger Network Security:

Segmentation splits the network into smaller subnetworks, isolating network traffic lessens the attack surface, obstructing lateral movement. Segmentation also isolates attacks before they spread. For instance, a malware infection in one subnetwork would not impact systems in another.

• Reduces Congestion, Better Performance:

Network segmentation reduces congestion. When a network has too many network hosts, congestion ensues because too many packets are transmitted. In some cases, performance can suffer to a degree wherein no packet is delivered. Subnetting, or breaking the network into small segments, relieves congestion significantly.

• Limit Cyber Attack Damage:

Segmentation improves cybersecurity by limiting how far an attack can spread. Segmentation keeps a malware outbreak in one section from affecting systems in another.

• Reduce the Scope of Compliance:

Compliance costs can be reduced using network segmentation, as it limits the amount of in-scope systems.