implementing-network-access-control

name	implementing-network-access-control
description	Implements 802.1X port-based network access control using RADIUS authentication, PacketFence NAC, and switch configurations to enforce identity-based access policies, posture assessment, and automatic VLAN assignment for authorized devices. . Use when working with implementing network access control.
domain	cybersecurity
tags	["network-security","nac","802.1x","radius","packetfence"]
subdomain	network-security
version	1.0
author	oyi77
license	Apache-2.0
nist_csf	["PR.IR-01","DE.CM-01","ID.AM-03","PR.DS-02"]

Implementing Network Access Control

Overview

Cybersecurity skill for implementing network access control. Follows industry best practices and security standards.

When to Use

Trigger phrases:

• "implementing network access control"

• "Implements 802"

• Enforcing identity-based network access where only authenticated and compliant devices connect to the network

• Implementing zero-trust networking at the access layer with dynamic VLAN assignment based on user role

• Quarantining non-compliant devices that fail endpoint posture checks (missing patches, disabled AV)

• Meeting compliance requirements (PCI-DSS, HIPAA, SOC 2) for network access controls

• Onboarding BYOD devices with automated provisioning and limited network access

Do not use as a standalone security solution without complementary controls, for networks with devices that do not support 802.1X supplicants, or without proper fallback mechanisms for critical infrastructure.

When NOT to Use

• When you lack proper authorization for testing
• For production systems without change management
• When the task requires legal or compliance expertise beyond technical scope

Prerequisites

• RADIUS server (FreeRADIUS, Microsoft NPS, or Cisco ISE) configured with user/device authentication
• Managed switches supporting 802.1X port-based authentication
• Certificate Authority for EAP-TLS certificate distribution (optional but recommended)
• PacketFence or similar NAC platform for posture assessment and remediation
• Active Directory or LDAP directory for centralized user authentication
• DHCP server integration for dynamic IP assignment per VLAN

Workflow

# Example: IOC detection
import re

IOC_PATTERNS = {
    "ip": r"\b(?:\d{1,3}\.){3}\d{1,3}\b",
    "domain": r"\b[a-z0-9-]+\.[a-z]{2,}\b",
    "hash_md5": r"\b[a-f0-9]{32}\b",
    "hash_sha256": r"\b[a-f0-9]{64}\b",
}

def extract_iocs() -> :
     {k: re.findall(v, text)  k, v  IOC_PATTERNS.items()}