May 2025
Strengthening Network Security:
Best Practices for Administrators
With more than twenty years of experience delivering Managed Security Services, investigating incidents, and protecting client networks, Network Box has distilled its frontline expertise into a clear set of Best Practices for network security.
These principles guide how our engineers design defense systems, process policy change requests, and conduct configuration reviews. They are the foundation of how we help organizations build stronger, more resilient security environments.
While every organization defines its own policies, our mission is to inform, warn, and advise whenever those policies conflict with proven security standards or expose networks to unnecessary risk.
This month, we are focusing on three critical areas that every network administrator must prioritize:
1. Remote administrative access
2. Effective policy control
3. Network segmentation
Nearly every major security breach we have assisted with in recent years has involved a breakdown in at least one of these three areas.
1. Remote Administrative Access: Close the Open Doors
Leaving remote administrative access open to the public Internet is like leaving the front door of a secure facility unlocked. Services such as Secure Shell (SSH), Remote Desktop Protocol (RDP), or Virtual Network Computing (VNC) are frequent targets for attackers who use brute-force attacks, credential stuffing, and software exploits to gain access.
Even when these services are password-protected, the entire system is only as strong as its weakest password. One careless user or unpatched system can expose the entire network.
To mitigate these risks, administrators should enforce strict access controls:
Require VPN or SD-WAN connections for all remote administrative access. These technologies ensure that only authenticated and authorized users can reach internal systems.
Enable Multi-Factor Authentication (MFA) to prevent password-based breaches.
Restrict access by IP address so that only trusted sources can connect.
Disable unused remote services completely.
By closing unnecessary doors, administrators significantly reduce the likelihood of unauthorized access.
2. Effective Policy Control: Enforcing Security at Every Level
Weak or inconsistent security policies can open invisible gaps that attackers are quick to exploit. Poor password management, over-privileged user accounts, or a lack of logging and monitoring can easily lead to a breach.
For instance, leaving default credentials such as “admin/admin” unchanged is still one of the most common and damaging mistakes.
Every organization should adopt strong, clearly defined security policies that are actively enforced:
Mandate complex, unique passwords that are rotated regularly.
Use Role-Based Access Control (RBAC) to ensure users have only the permissions they need.
Conduct regular security audits to identify policy weaknesses and take corrective action.
Implement centralized logging and monitoring to detect suspicious activity early.
Policy control is not just about compliance. It is about accountability, visibility, and ensuring that every action taken on your network leaves a trace.
3. Network Segmentation: Containing Threats Before They Spread
A flat network, where every device can communicate freely, is a hacker’s dream. Once an attacker breaches a single system, they can move laterally across the entire network without resistance.
Proper network segmentation prevents this. By dividing the network into smaller, isolated zones, administrators can control and monitor how information flows between systems.
Use Virtual Local Area Networks (VLANs) and firewalls to separate sensitive resources from general access zones.
Define strict communication rules so that only necessary traffic passes between segments.
Review and update inter-segment policies regularly to remove outdated or unnecessary connections.
Segmentation turns what could have been a full-scale breach into a contained event. It limits damage, protects critical systems, and gives administrators valuable time to respond.
Building a Culture of Continuous Security
Security is not a single task: it is an ongoing process that evolves alongside the threats it defends against. Regular policy reviews, configuration audits, and vulnerability scans are essential to maintaining a strong posture.
At Network Box USA, we conduct external view scans and policy reviews to help clients identify conflicts, gaps, and common attack vectors. We inform and advise, but ultimately, you decide the policy.
By following these best practices (closing unnecessary remote access, enforcing strict policies, and segmenting your network) you create a stronger, more adaptable defense. The result is not just compliance, but true resilience against modern cyber threats.
