What Is DMZ Network? A Basic Overview For 2021

Introduction

DMZ helps to protect the organization’s private network by putting in an extra layer of security. For instance, In Korea, there is a four-kilometre wide strip of land that divides north from the south is called the dematerialized zone or DMZ. This strip of land is a security measure between the two nations. After the war, DMZ was created as a physical buffer to prevent or limit the effectiveness of an attack from another side. So, if one layer fails or is ineffective, another layer can mount a defence. From this, we get the network security concept of a DMZ.  In this article, we will learn about what is dmz, dmz server, what is dmz server, and dmz architecture.

To add security, there are firewalls and IPS between all of the networks. This adds up to several layers of security that need to be compromised before an attacker can reach our protected resources. Like the airlock chamber on spacecraft, a DMZ network keeps sensitive data safe from the external world. A DMZ network is placed between the internet and a company’s private network and is managing access and flow of traffic.

1. What is DMZ network?
2. How does a DMZ network work?
3. Benefits of using DMZ network
4. DMZ design and architecture
5. The Importance of DMZ Networks

1. What is DMZ network?

DMZ stand for The demilitarized zone (DMZ), also known as a perimeter network, is located between networks to improve the security of an organization’s network by preventing direct access from the insecure network to a protected network. In other words, DMZ is the network between the insecure area and the protected area. We will put the services that are allowed to be accessed from the internet inside the DMZ. We will keep our sensitive data out of the DMZ. So it’s like establishing two distinct networks, one external network that is exposed in the DMZ, and the other one is the company’s local area network (LAN) that is not exposed and is protected. 

In the military world, it’s an area where military operations are forbidden, or in space travel, it’s like the air chamber that enables astronauts to go in safely and out of space crafts and in the networking world, it’s a buffer zone that adds security to organization’s local area network.  

2. How does a DMZ network work?

Any device that is exposed to the internet will take most of the brunt of most attacks and therefore assumes the most risk. Companies with public servers that need to be accessed by people outside the organization are generally exposed to more attacks. DMZs act like a buffer zone between an external network and an internal network. Building a DMZ between two firewalls means that all incoming traffic is screened using a firewall or security appliance or firewall before they reach the organization’s server.

If a skilled bad guy has found a way past the company’s firewall and gains unauthorized access to those systems before they do any malicious activity or reach to organization’s sensitive data, those systems warn the host that a breach is underway.

3. Benefits of using DMZ network

The main purpose of using the DMZ network is to allow an organization to access necessary internet services securely. The DMZ network has various benefits. Some of these are as follows:

• Facilitate Access Control: An organization can give users access to services outside the organization’s network perimeter through the external network such as the internet. An additional layer of protection makes sure that only legitimate traffic can access the DMZ and also makes it a lot harder for the hackers to penetrate the company’s internal network because they would have to go through two different firewalls if they want to try and access the company’s internal network. 
• Prevents network reconnaissance: DMZ network allows an organization to access necessary internet services securely. It functions as a buffer and prevents a hacker from performing network reconnaissance. Even if a DMZ system gets compromised, the internal firewall isolates the protected network from the DMZ network and keeps it safe, and prevents external reconnaissance by the attacker by making it a lot harder. So compromising one part of the system has not compromised the entire system.
• Protects from Internet Protocol (IP) spoofing: Attackers can try to get access to systems by spoofing a legitimate IP address and impersonate other authorized devices on a network. A DMZ can detect and block potential spoofing efforts while another service authenticates the validity of the IP address. The DMZ also lays out a network segmentation that organizes an area where traffic can be arranged and public services to be accessed at a safe distance from the organization’s private network.

The most common services that are provided to users on the public network are listed below:

•           Web servers

•           Mail servers

•           FTP servers

•           DNS servers

•           Proxy servers

•           VoIP servers

Any service provided to users on the public internet should be placed in the DMZ network to prevent direct access from insecure networks to a protected network.

4. DMZ design and architecture

There are several ways to construct a network with DMZ. Most modern designs use two firewalls. 

• Single firewall: This design requires at least three network interfaces. The first one is the external network, which links the external network via an internet service provider (ISP) connection to the firewall. The internal private network interface is the second, while the third is linked to the DMZ. The firewall act as a shield for the network and must be able to manage all of the traffic going to the DMZ as well as the private network. 
• Dual firewall: It is generally more secure. There is one firewall to allow external traffic flow to the DMZ and another one to allow traffic from the DMZ to the internal network. An extra layer of protection to make sure that only legitimate traffic can access the DMZ and also makes it a lot harder for the hackers to penetrate the company’s internal network because they would have to go through two different firewalls if they want to try and access the company’s internal network.

5. The Importance of DMZ Networks

DMZ networks are important in securing an organization’s network, sensitive information, systems, and resources by keeping a private network away from the systems that can be a potential target for the attackers.

• The main purpose of using a DMZ is that it provides an additional layer of security to the organization’s private network by restricting access to servers and sensitive data of the organization. 
• We can put a reverse proxy server in the DMZ. Clients on the internet will access the reverse proxy server that does not have any sensitive data.
• DMZ is not only isolates and keeps potential target systems from internal networks but also reduces and controls access to those systems.
• With DMZ, users within the organization can still share and access content on the public internet, and unauthorized users outside of a network can still access relevant data from the network.
• Since a DMZ controls both external and internal traffic flow to and from a private network, there’s less possibility of hackers directly accessing the company’s system.
• DMZ is also useful in responding to the security threats posed by IoT devices, OT systems, etc.

Conclusion

Therefore, understanding the DMZ network is crucial in securing the organization’s sensitive data while using an unprotected network such as the internet. Hopefully, this article has helped in explaining it.

So, have you made up your mind to make a career in Cyber Security? Visit our Cyber Security Courses for further help. It is the first program in offensive technologies in India and allows learners to practice in a real-time simulated ecosystem, that will give you an edge in this competitive world.

ALSO READ

• 2021 Guide About Digital Security