Broadcasting Many SSIDs

TL;DR

Broadcasting 10,000 unique SSIDs is generally not practical or recommended due to limitations of Wi-Fi hardware and security concerns. However, you can achieve a similar effect by using multiple access points (APs) and carefully managing your SSID list. This guide outlines how to do this effectively.

Understanding the Limitations

Standard Wi-Fi equipment has limits on the number of SSIDs it can broadcast simultaneously. These limitations stem from both hardware capabilities and potential performance impacts. Broadcasting a very large number of SSIDs will likely cause:

• Reduced Performance: The AP spends more time scanning for clients and managing different SSIDs, reducing overall throughput.
• Increased Overhead: More beacon frames are transmitted, increasing network congestion.
• Client Compatibility Issues: Some older devices may struggle to handle a large number of available networks.

Solution: Multiple Access Points

The most practical approach is to distribute the SSIDs across multiple access points.

Step 1: Determine Hardware Requirements

1. AP Capacity: Check the specifications of your chosen APs. Most enterprise-grade APs can handle a reasonable number (e.g., 16-32) of SSIDs, but consumer-grade APs often have lower limits (e.g., 4).
2. Number of APs: Divide the total number of SSIDs (10,000) by the capacity of each AP to determine how many APs you’ll need. For example, with APs that support 32 SSIDs, you would require approximately 313 APs (10,000 / 32 = 312.5).
3. Coverage: Ensure sufficient coverage across your desired area by strategically placing the APs. Overlapping signal ranges are important for seamless roaming.

Step 2: Configure Access Points

1. SSID Assignment: Divide the list of 10,000 SSIDs evenly among your access points. Keep a clear record of which APs are broadcasting which SSIDs.
2. Security Settings: Implement strong security protocols (WPA3 is recommended) for each SSID. Avoid using weak or default passwords.
3. Channel Selection: Configure non-overlapping channels on your access points to minimize interference. Use a Wi-Fi analyzer tool to identify the least congested channels in your environment.

   iwconfig wlan0 channel 1

   (example command for Linux, adjust interface name as needed)

4. DHCP Configuration: Ensure each AP has its own DHCP scope or is configured to use a central DHCP server with sufficient address pools.

Step 3: Centralized Management (Recommended)

Managing hundreds of access points individually can be challenging. Consider using a centralized Wi-Fi management platform.

• Controller Software: Options include cloud-based solutions or on-premise controllers from vendors like Ubiquiti, Cisco Meraki, or Aruba Networks.
• Benefits: Centralized configuration, monitoring, firmware updates, and troubleshooting capabilities.

Step 4: Testing and Optimization

1. Roaming Tests: Verify seamless roaming between access points as clients move around the coverage area.
2. Performance Monitoring: Monitor network performance (throughput, latency) to identify any bottlenecks or issues caused by the large number of SSIDs.
3. Client Device Compatibility: Test with a variety of client devices to ensure compatibility and optimal connectivity.

Security Considerations

Broadcasting many SSIDs can increase your cyber security risk.

• SSID Spoofing: Attackers could create rogue access points with similar SSIDs to trick users into connecting.
• Management Overhead: More SSIDs mean more configurations to maintain and secure, increasing the potential for errors or vulnerabilities.
• MAC Address Filtering (Not Recommended): While possible, MAC address filtering is easily bypassed and doesn’t provide strong security.

Prioritize strong encryption (WPA3), regular security audits, and intrusion detection/prevention systems to mitigate these risks.