Perimeter Security: Defend Your Network Against Malicious Attacks

Perimeter Security technologies offer a wide range of security services, from basic firewall protection to end-to-end network and business security. In essence, perimeter security is a defense system built around your network to prevent malicious attacks from entering.

The need for securing the perimeter of the network

Hackers launch attacks every 39 seconds, or 2,244 times per day. Small businesses are the target of 43 percent of cyber-attacks, and 64 percent of businesses have experienced web-based attacks. Phishing and social engineering attacks were experienced by 62% of respondents. Malicious code and botnets were experienced by 59% of businesses, and denial of service attacks were experienced by 51%.

The statistics are concerning, but this is largely due to the fact that many businesses do not adequately defend their networks. When deciding what type of security to implement, cost can be a factor. The average cost of a ransomware attack on a business is $133,000, so cybersecurity should be viewed as an investment rather than an expense.

What Is Perimeter Security?

In the IT world, perimeter security entails protecting a company’s network boundaries from hackers, intruders, and other undesirable individuals. It entails detecting surveillance, analyzing patterns, recognizing threats, and dealing with them effectively. Every private network is surrounded by a perimeter. It acts as a secure barrier between networks, such as your company’s private intranet and the ‘public’ internet.

In the cases of big organizations, the security perimeter is secured by the network support company, or, in some cases, the internal IT department, deploys systems that keep your network secure from public web threats. Hacking attempts, malware, ransomware, and other infiltration attempts are among the threats.

There are a few components of a network perimeter including:

  • firewalls
  • border routers
  • Intrusion Detection Systems (IDS)
  • Intrusion Prevention Systems (IPS)
  • Unified Threat Management (UTM) systems

Border Routers

Routers are devices that direct traffic into and out of networks; border routers are the last on a company’s private network before traffic is routed to public networks on the internet.


A firewall is a device that contains a filtering mechanism and a predefined set of rules that allow and restrict traffic from the public network to enter the private network and vice versa. It is an additional safeguard designed to protect a company’s network from unwanted data packets that may contain threats.

Intrusion Detection Systems – IDS

Intrusion detection systems monitor network traffic and information ‘packets’ as they travel between public and private networks.

It compares all data to a known list of cyber-attack signatures and the IT department should take the necessary steps to prevent harmful data from entering your company’s private network.

They can compare network activity to a prebuilt threat database, which detects various security violations, port scanners, and malware.

The IDS is essentially an alarm system that notifies the company of any suspicious activity. It can be constructed from a single device or from strategically placed sensors on different points of a network.

Intrusion Prevention Systems – IPS

Intrusion prevention systems are control systems that can accept or reject data packets based on a predefined set of rules that are either manually or automatically updated by your managed service provider. In contrast to a traditional IDS system that alerts administrators and MSPs to threats, intrusion prevention systems can include an automated defense mechanism that prevents data from entering the network without the need for human intervention.

Unified Threat Management (UTM) Systems

Unified Threat Management (UTM) systems safeguard the network by combining IDS and IPS features. From a single point in the private network, a single security device performs multiple security functions. The information entering a company’s network is protected by antivirus, firewall, anti-spyware, anti-spam, virtual private network (VPN), and other functions.

Because of deep packet inspection, a UTM system protects against viruses, hacking attempts, malware, malicious attachments, and other threats. Deep packet inspection (DPI) evaluates the data being transmitted over the network from the inside out and checks for compliance violations such as spam, Trojans, viruses, or other defined criteria. If it detects these violations, it prevents data from being received or transmitted.Defining & Defending The Network Perimeter

To provide the best possible security, your IT department must understand the entire layout of your network perimeter. Continuous scanning and assessment of this perimeter can assist you in determining when company resources and data are being misused by individuals or are under attack by hackers. However, it has become dynamic as a result of the ability to work remotely and with your own devices (BYOD), but this does not negate the fact that entry and exit points for a private network, such as that of a business, must be protected.

Monitor Passively

Passive monitoring tools can be useful for discovering network-connected devices and determining how much access and discretion they have been granted. These tools scan the network for flaws and vulnerabilities, locating the various devices that are connected to it.

Remote servers, routers, desktops, security devices, application routers, and firewalls are examples of such devices. The monitoring tool can examine these devices’ configuration, operating system, installed apps, and patch levels to identify vulnerabilities that allow hackers unauthorized access. To perform vulnerability checks, the IT department must manually activate or schedule the passive tools.

Monitor Actively

Active monitoring tools allow for continuous network surveillance, scanning for irregular traffic patterns, unknown IP structures, communications, and data transmission. These tools can assist the IT department in mapping out the architecture for your company’s private network and in establishing guidelines for network communication between devices. This assists your employees in adhering to company policies.

These tools monitor your most critical business assets and apps, taking action against unauthorized access, employee resource misappropriation, malicious content, and other security ramifications. They audit your security in real time, creating logs and reports to ensure compliance with security policies.

Network Zoning

The concept of zoning considers all areas of a network and categorizes them as controlled, uncontrolled, restricted, or secure. The main benefit of zoning is that it confines a potential security breach to the individual zones where it occurred, preventing it from spreading to other zones. Network boundaries aid in the separation of networking zones with varying security policies. These boundaries impose restrictions on the types of traffic permitted in various zones. For example, HTTP traffic may be restricted to specific ports, or HTTPs traffic from other public network ports may be restricted (internet and other uncontrolled networks).

Firewalls can be used to allow and restrict traffic – the firewall sends back the information packet or traffic from which it originated by readdressing – the traffic being sent back appears to have originated from an address connected to the firewall. The identity of the trusted network is thus concealed from the other untrusted networks connected to the internet.

Mitigating risks from remote work

A solid remote security policy is essential for day-to-day operations and network resilience. Here are some strategies that employers can use to protect their data regardless of location.

1. Move your applications to the cloud

Cloud applications such as Office 365 and QuickBooks Online provide access 24 hours a day, seven days a week. They include updated security features that are in accordance with industry standards.

2. Use VPNs to connect

VPNs, or virtual private networks, are similar to firewalls. They are one of the most popular remote worker security tools because they protect laptop data online while maintaining the same security, functionality, and appearance as if they were on the company network.

3. Implement multi-factor authentication

Many businesses are hesitant to implement multi-factor authentication because it is inconvenient. Many people would prefer not to wait for an authentication code. This one practice, on the other hand, is remarkably effective in preventing security breaches.

4. Enforce BYOD/MDM Policies

Enforcing BYOD (bring your own device) and MDM (mobile device management) policies safeguards users against a variety of threats.

5. Use password managers

To ensure password security, require employees to use encrypted password software. Password managers that are popular include: 1Password, LastPass etc.

6. Training on best security practices

Establish clear security guidelines, so that everyone knows how to protect themselves and their data.

Final words

Perimeter security is a philosophy that involves setting up functional devices, tools, and techniques around the boundary of a network to secure its data and resources. It is one facet of the greater security field and plays a vital role in active system protection.

So essentially, perimeter security experts take a perimeter-based approach to secure your systems and ward off any threats before they enter the network. They follow best practices like threat recognition, pattern analysis, and surveillance detection to set up high-quality and highly efficient processes to ensure internal security. If you would like to know more about perimeter security or have any questions or concerns that need answering, please don’t hesitate to get in touch, or browse our blog for more free articles.

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