Passwordless WiFi: What It Is and How to Implement It

This technical reference guide provides network architects and IT managers with a comprehensive blueprint for transitioning from vulnerable shared passwords to secure, certificate-based WiFi authentication. It covers 802.1X architecture, EAP-TLS deployment strategies, PKI management, and the measurable business impact of reducing helpdesk overhead while enhancing enterprise security posture and compliance readiness.

📖 8 min read📝 1,800 words🔧 2 examples❓ 3 questions📚 8 key terms

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[0:00 - 1:00] Introduction & Context
Hello, and welcome to this technical briefing from Purple. I'm your Senior Solutions Architect for today's session, and we're tackling a critical architectural shift for enterprise networks: the move to Passwordless WiFi.

If you're an IT director at a retail chain, managing a large hotel, or overseeing a public sector campus, you already know the pain of the Pre-Shared Key — the PSK. It's the single password that everyone shares. It's a security nightmare, it makes compliance audits like PCI DSS incredibly painful, and frankly, it's a massive drain on your helpdesk. Every time a staff member leaves, you technically should rotate that password. But you don't, because it breaks connectivity for every scanner, tablet, and laptop in the building. Today, we're discussing the solution: certificate-based, identity-aware WiFi authentication. It's secure, it's scalable, and it fundamentally changes the operational economics of managing wireless access. Let's dive into the architecture.

[1:00 - 6:00] Technical Deep-Dive
To understand passwordless WiFi, we need to look at the IEEE 802.1X standard. This isn't new technology, but the way we deploy it at scale has evolved significantly.

802.1X relies on three components. First, the Supplicant — that's the client device, your laptop or smartphone. Second, the Authenticator — typically your Wireless Access Point. And third, the Authentication Server — your RADIUS server, tied to an Identity Provider, or IdP, like Active Directory or Okta.

When we say 'passwordless' in an enterprise context, we are almost always talking about EAP-TLS — Extensible Authentication Protocol with Transport Layer Security. EAP-TLS is the gold standard because it mandates mutual authentication. The network proves it's legitimate to the device — preventing evil twin attacks — and the device proves its identity to the network using a unique digital certificate. No passwords are ever transmitted over the air.

The engine behind this is your Public Key Infrastructure, or PKI. This used to be a massive headache to set up on-premise. But today, cloud-managed PKI and RADIUS solutions have commoditised this infrastructure significantly.

The real magic happens in device onboarding. For your corporate assets — the laptops and managed tablets — you leverage your Mobile Device Management platform, like Intune or Jamf. The MDM uses a protocol called SCEP — Simple Certificate Enrollment Protocol — to silently request a certificate from the Certificate Authority and push it to the device. It's zero-touch for the user. They open their laptop, and it's securely connected. No password required. No helpdesk call needed.

For unmanaged devices — BYOD, or guests — we use onboarding portals. The user authenticates once against their corporate directory, or perhaps via a captive portal for guests, and a temporary certificate or a Passpoint profile is pushed to their device.

Speaking of Passpoint, or Hotspot 2.0, this is crucial for venues like stadiums, conference centres, or large retail environments. It allows devices to automatically discover and connect to authorised networks, much like cellular roaming. This is where platforms like Purple add immense value. Purple can act as the Identity Provider for services like OpenRoaming. A guest walks in, their device recognises the network, authenticates securely in the background using a certificate, and they are online. No captive portal every time they visit, but you still get the analytics and engagement capabilities on the back end.

Furthermore, 802.1X allows for dynamic VLAN assignment. The RADIUS server looks at the certificate, identifies the user's group, and tells the Access Point to place them on a specific VLAN. Your point-of-sale terminals are isolated from your corporate staff, who are isolated from the guest network. This is precisely how you achieve compliance and limit your blast radius in the event of a security incident.

[6:00 - 8:00] Implementation Recommendations & Pitfalls
When you're ready to deploy, take a phased approach.

First, audit your infrastructure. Ensure your Wireless LAN Controllers and Access Points support WPA3-Enterprise and 802.1X. Legacy hardware may require firmware updates or replacement.

Second, get your PKI and RADIUS sorted. I strongly recommend cloud-RADIUS for scalability and redundancy. On-premises RADIUS servers become single points of failure in distributed deployments.

Third, nail the onboarding experience. If it's hard for users to get their certificates, your helpdesk will be overwhelmed during the transition.

Now, what are the pitfalls? The biggest one is clock skew. EAP-TLS relies heavily on cryptography, which in turn relies on accurate time. If the time on your client device is out of sync with your RADIUS server, the certificate validation will fail — silently. The user just can't connect, and they don't know why. Ensure everything is syncing to a reliable NTP source.

Another common issue is certificate chain trust. If the client device doesn't have the root CA and any intermediate Certificate Authorities installed, it will reject the server's certificate. Always ensure your RADIUS server is configured to send the full certificate chain during the EAP exchange.

Finally, don't just turn off the old PSK network overnight. Run both SSIDs in parallel, but throttle the bandwidth on the legacy network to incentivise users to migrate to the secure SSID. Give yourself four to six weeks for the transition.

[8:00 - 9:00] Rapid-Fire Q&A
Question one: Is passwordless WiFi only for large enterprises? Not anymore. Cloud-managed RADIUS and PKI have made this accessible for mid-market organisations as well. The operational savings — in helpdesk reduction alone — often justify the investment within the first year.

Question two: What happens if a device is lost or stolen? This is the beauty of EAP-TLS. You don't change a password that affects every single user on the network. You simply revoke that specific device's certificate in your PKI. The RADIUS server checks the Certificate Revocation List, or uses OCSP — the Online Certificate Status Protocol — and immediately blocks that device from the network. Surgical, precise, and instant.

[9:00 - 10:00] Summary & Next Steps
To summarise, moving to passwordless WiFi via 802.1X and EAP-TLS is a strategic imperative for any organisation managing WiFi at scale. It eliminates the security vulnerabilities of shared passwords, it enables granular network segmentation for compliance with frameworks like PCI DSS and GDPR, and it drastically reduces helpdesk overhead.

For your next steps, I recommend conducting an infrastructure readiness assessment this quarter. Evaluate cloud-RADIUS providers, and look closely at how platforms like Purple can streamline the onboarding process — especially for guest and BYOD scenarios — turning what is fundamentally a security upgrade into a genuine business enablement tool.

Thank you for your time today. If you'd like to explore how Purple can support your passwordless WiFi deployment, visit purple dot ai.

Key Takeaways

✓Passwordless WiFi replaces shared passwords (PSKs) with unique digital certificates per device, fundamentally improving enterprise network security.
✓The IEEE 802.1X standard with EAP-TLS provides mutual authentication — both the device and the network verify each other's identity cryptographically.
✓Eliminating shared passwords drastically reduces helpdesk tickets related to connectivity issues, password rotation, and credential compromise.
✓Deployment requires three core components: a RADIUS server, an Identity Provider (IdP), and a Public Key Infrastructure (PKI) for certificate lifecycle management.
✓Mobile Device Management (MDM) with SCEP enables zero-touch certificate provisioning for corporate assets, requiring no user interaction.
✓Passpoint (Hotspot 2.0) and platforms like Purple provide seamless, secure onboarding for guest and BYOD access, acting as an IdP for OpenRoaming.
✓Dynamic VLAN assignment via RADIUS enables granular network segmentation based on user identity, a key requirement for PCI DSS and GDPR compliance.

Executive Summary

The transition from shared Pre-Shared Keys (PSKs) to certificate-based, passwordless WiFi authentication represents a critical architectural shift for enterprise networks. For IT managers and network architects operating at scale — whether across a 200-room hotel, a national retail chain, or a sprawling public-sector campus — the legacy approach of managing a single password for all guest or BYOD access is no longer viable. It introduces unacceptable security vulnerabilities, complicates compliance with frameworks like PCI DSS and GDPR, and generates a disproportionate volume of helpdesk tickets related to connectivity issues and password rotation.

Passwordless WiFi, fundamentally built upon the IEEE 802.1X standard and EAP-TLS (Extensible Authentication Protocol - Transport Layer Security), eliminates these friction points. By issuing unique, cryptographically secure certificates to individual devices, network administrators can enforce granular, identity-aware access control. This guide provides a comprehensive technical reference for implementing passwordless WiFi, detailing the underlying architecture, deployment methodologies, and the measurable return on investment (ROI) achievable through reduced operational overhead and mitigated risk. Furthermore, we explore how integrating a platform like Purple's Guest WiFi can streamline this transition, acting as a robust Identity Provider (IdP) to facilitate seamless, secure onboarding.

Technical Deep-Dive: The Architecture of Passwordless WiFi

To understand the implementation of passwordless WiFi, one must first deconstruct the core components of the 802.1X authentication framework. Unlike WPA2-Personal, which relies on a shared secret, 802.1X operates on a tripartite model: the Supplicant, the Authenticator, and the Authentication Server.

The 802.1X Tripartite Model

The Supplicant is the client device — a smartphone, laptop, or IoT sensor — attempting to connect to the network. In a passwordless environment, the supplicant must possess a valid digital certificate rather than a password. The Authenticator is typically the Wireless Access Point (WAP) or wireless LAN controller. It acts as a gatekeeper, not evaluating credentials itself, but encapsulating the supplicant's request and forwarding it to the authentication server via the RADIUS protocol. The Authentication Server is the centralized authority — often a RADIUS server integrated with an Identity Provider (IdP) such as Active Directory, LDAP, or a cloud-native directory service. The server validates the certificate presented by the supplicant against its database and a Certificate Revocation List (CRL).

EAP-TLS: The Gold Standard for Passwordless Authentication

While 802.1X supports various Extensible Authentication Protocol (EAP) methods, EAP-TLS is universally recognised as the most secure standard for enterprise deployments. EAP-TLS mandates mutual authentication: the RADIUS server presents its certificate to the supplicant, proving the network is legitimate and preventing evil twin attacks; and the supplicant presents its unique client certificate to the RADIUS server, proving its identity without transmitting any password hashes over the air. This mutual cryptographic handshake establishes a secure TLS tunnel through which the final authorisation and key derivation occur, ensuring maximum data integrity and confidentiality.

The Role of Public Key Infrastructure (PKI)

Implementing EAP-TLS requires a robust Public Key Infrastructure (PKI). The PKI is responsible for generating, issuing, and managing the lifecycle of digital certificates. Historically, managing a local Certificate Authority (CA) was a significant barrier to entry. However, modern cloud-managed PKI solutions and Mobile Device Management (MDM) integrations have automated the provisioning process, allowing certificates to be pushed silently to managed devices via protocols like SCEP (Simple Certificate Enrollment Protocol) or EST (Enrollment over Secure Transport).

For unmanaged devices — BYOD or guest access — onboarding platforms provide a self-service portal where users authenticate once (e.g., via OAuth or SAML against a corporate directory, or via a captive portal for guests) and are subsequently provisioned with a temporary certificate or a secure profile such as Passpoint/Hotspot 2.0.

Implementation Guide: Step-by-Step Deployment

Deploying a passwordless WiFi architecture requires careful planning and phased execution. The following steps outline a vendor-neutral approach suitable for large-scale enterprise environments, such as those found in Healthcare or Transport sectors.

Phase 1: Infrastructure Assessment and Readiness

Before altering authentication methods, ensure the underlying network infrastructure supports the required protocols. Verify that all Wireless LAN Controllers and Access Points support 802.1X and WPA3-Enterprise — legacy hardware may require firmware updates or replacement. Select a robust RADIUS solution capable of handling the expected authentication load; cloud-RADIUS solutions offer high availability and scalability compared to on-premises deployments. Determine the primary source of truth for user identities (e.g., Azure AD, Okta, Google Workspace) and confirm the RADIUS server can communicate with this directory.

Phase 2: PKI Setup and Certificate Management

The foundation of passwordless access is certificate lifecycle management. Deploy a trusted Certificate Authority: for internal corporate devices, an internal CA is sufficient; for guest access or BYOD, consider a public CA or a specialised onboarding service. Define clear certificate validity policies — corporate devices might receive certificates valid for one year, while guest certificates might expire after 24 hours. Configure revocation mechanisms, ensuring the RADIUS server checks Certificate Revocation Lists (CRLs) or uses OCSP to immediately block access for lost or compromised devices.

Phase 3: Device Onboarding and Provisioning

The onboarding experience dictates the success of the deployment. For managed corporate devices, leverage an MDM solution (e.g., Microsoft Intune, Jamf) to silently push the CA certificate and the unique client certificate using SCEP or EST. This requires zero user interaction. For unmanaged BYOD devices, implement a secure onboarding portal where users connect to an open provisioning SSID, authenticate via corporate credentials (SAML/OAuth), and download a configuration profile that installs the necessary certificates and configures the secure SSID. For guest access in environments like Hospitality or Retail , integrate with a platform like Purple's WiFi Analytics . Purple can act as the IdP, allowing guests to authenticate via social login or a customised portal, after which they are seamlessly transitioned to a secure, encrypted connection — often leveraging OpenRoaming or Passpoint standards — without ever typing a network password.

Phase 4: Network Configuration and Testing

Create the new SSID configured for WPA3-Enterprise (or WPA2-Enterprise if legacy support is required) and 802.1X authentication, pointing the authenticator to the RADIUS server. Configure the RADIUS server to return specific attributes upon successful authentication — for example, assigning the user to a specific VLAN based on their group membership, placing staff on a corporate VLAN and guests on an isolated internet-only VLAN. Roll out the secure SSID to a small pilot group first (the IT department is usually ideal) and monitor authentication logs meticulously to identify any certificate validation errors or RADIUS timeouts before a full deployment.

Best Practices for Enterprise Environments

Enforce Mutual Authentication: Never deploy EAP-TLS without requiring the supplicant to validate the server's certificate. Failure to do so exposes the network to Man-in-the-Middle (MitM) attacks.

Implement Strict Certificate Validation: Configure supplicants to explicitly trust only the specific CA that issued the RADIUS server's certificate, and verify the server's Common Name (CN) or Subject Alternative Name (SAN).

Leverage Passpoint (Hotspot 2.0): For public-facing venues, Passpoint is the future of passwordless connectivity. It allows devices to automatically discover and securely connect to authorised networks using credentials provided by their mobile operator or a third-party IdP, functioning much like cellular roaming. Purple's Connect licence facilitates this by acting as an identity provider for services like OpenRoaming.

Segment Traffic: Always use dynamic VLAN assignment via RADIUS to logically separate different classes of users (POS terminals, corporate staff, IoT devices, guests). This limits the blast radius of any potential compromise. For a deeper dive into segmenting specialised networks, see our guide on WiFi in Hospitals: A Guide to Secure Clinical Networks .

Troubleshooting & Risk Mitigation

Even with meticulous planning, issues can arise. Understanding common failure modes is critical for rapid resolution.

Clock Skew is the single most common cause of EAP-TLS authentication failures. Certificate validation relies on accurate timekeeping; if the time on the supplicant, RADIUS server, or CA is out of sync by more than a few minutes, validation will fail silently. Ensure all infrastructure relies on a reliable NTP source.

Certificate Chain Issues occur when the supplicant does not have the complete chain of trust — including intermediate CAs — installed. It will reject the server's certificate. Always ensure the RADIUS server is configured to send the full certificate chain during the EAP exchange.

RADIUS Timeouts can occur if the latency between the authenticator (WAP) and the RADIUS server is too high, causing the EAP handshake to time out. This is common in distributed deployments using a centralised cloud RADIUS. Adjust timeout values on the WLC or consider deploying regional RADIUS proxies.

Stale Certificates: Devices attempting to authenticate with expired certificates will be silently rejected. Implement robust monitoring to alert administrators of impending certificate expirations before they impact users.

For risk mitigation, maintain the legacy PSK network temporarily during the transition, but restrict its bandwidth or access privileges to incentivise migration. Forward all RADIUS authentication logs to a SIEM platform and conduct periodic reviews of the PKI infrastructure and RADIUS policies to ensure alignment with current security standards.

ROI & Business Impact

The transition to passwordless WiFi is a strategic investment with a measurable return across several dimensions.

Metric	Shared PSK	Certificate-Based (802.1X)
Helpdesk tickets (connectivity)	High — frequent password resets	Near-zero — automated provisioning
Security risk	High — single credential for all	Low — unique, revocable per device
Compliance readiness	Poor — no individual accountability	Strong — full audit trail per device
Onboarding time (corporate)	Minutes (manual)	Seconds (MDM automated)
Credential revocation	Disruptive — requires full PSK rotation	Instant — revoke individual certificate

Reduction in Helpdesk Overhead: Managing shared passwords is a significant drain on IT resources. Passwordless authentication, particularly when automated via MDM or a self-service onboarding portal, virtually eliminates password-related helpdesk tickets.

Enhanced Security Posture: By eliminating shared secrets, the risk of credential theft and unauthorised network access is drastically reduced. Each device has a unique, cryptographically secure identity that can be instantly revoked if the device is lost or compromised.

Simplified Compliance: Frameworks like PCI DSS require strict access controls and individual accountability. Certificate-based authentication provides a clear audit trail of exactly which device accessed the network and when, simplifying compliance reporting.

Improved User Experience and Data Capture: Once provisioned, the connection process is entirely transparent to the user. In environments like Retail , this frictionless connectivity encourages users to join the network, allowing venues to capture valuable first-party data and drive personalised engagement through platforms like Purple.

For organisations managing complex RF environments, understanding the interplay between authentication and physical infrastructure is crucial. Further reading on infrastructure considerations can be found in Your Guide to a Wireless Access Point Ruckus . Additionally, understanding how broader networking concepts apply can be useful; see our guide on Personal Area Networks (PANs): Technologies, Applications, Security, and Future Trends .

Key Terms & Definitions

802.1X

An IEEE standard for port-based network access control, providing an authentication mechanism to devices wishing to attach to a LAN or WLAN. It is the foundational protocol for enterprise-grade, passwordless WiFi.

The core standard that underpins all enterprise WiFi authentication, replacing the shared PSK model.

EAP-TLS (Extensible Authentication Protocol - Transport Layer Security)

A highly secure EAP method that requires mutual authentication using digital certificates on both the client and the server. No passwords are transmitted over the air.

Considered the gold standard for wireless security. The method of choice for any organisation serious about eliminating credential-based risk.

RADIUS (Remote Authentication Dial-In User Service)

A networking protocol that provides centralised Authentication, Authorisation, and Accounting (AAA) management for users who connect and use a network service.

The engine that processes authentication requests from Access Points and validates them against a directory. A RADIUS server is a mandatory component of any 802.1X deployment.

Supplicant

The client device (e.g., laptop, smartphone, IoT sensor) attempting to access the network. In 802.1X, the supplicant must present a valid certificate or credential to gain access.

The starting point of every authentication request. Understanding the supplicant's capabilities (e.g., whether it supports EAP-TLS) is critical during the planning phase.

PKI (Public Key Infrastructure)

A set of roles, policies, hardware, software, and procedures needed to create, manage, distribute, use, store, and revoke digital certificates and manage public-key encryption.

The underlying system required to issue and manage the certificates used in EAP-TLS. Without a functioning PKI, certificate-based authentication is not possible.

Passpoint (Hotspot 2.0)

A Wi-Fi Alliance standard that streamlines network access, allowing devices to automatically discover and connect to authorised WiFi networks without manual authentication steps.

Enables a seamless, cellular-like roaming experience for users across different venues. Particularly relevant for hospitality, retail, and public-sector deployments.

Dynamic VLAN Assignment

The process where a RADIUS server instructs the Authenticator to place a successfully authenticated user onto a specific Virtual LAN based on their identity or group membership.

Crucial for network segmentation, ensuring that IoT devices, guests, and corporate staff are logically isolated from one another — a key requirement for PCI DSS compliance.

SCEP (Simple Certificate Enrollment Protocol)

A protocol that enables network devices to automatically request and receive digital certificates from a Certificate Authority, typically orchestrated by an MDM solution.

The mechanism that enables zero-touch certificate provisioning for corporate devices, eliminating the need for manual certificate installation.

Case Studies

A national retail chain with 500 locations is currently using a single WPA2-Personal (PSK) network for both store operations (inventory scanners, POS tablets) and corporate staff laptops. The IT director needs to improve security to meet PCI DSS compliance and reduce the operational burden of rotating the PSK every time an employee leaves. How should they implement passwordless WiFi?

Deploy a Cloud-RADIUS solution integrated with the central Identity Provider (e.g., Azure AD). 2. For corporate laptops, use the existing MDM (Microsoft Intune) to push a unique client certificate via SCEP, configuring devices to connect to a new 'Corp-Secure' SSID using EAP-TLS. 3. For inventory scanners and POS tablets, utilise an onboarding portal to provision device-specific certificates, binding them to a dedicated 'Ops-Secure' VLAN via RADIUS attributes. 4. Retain the PSK network temporarily, but change the password and restrict it to a quarantine VLAN to identify legacy devices that failed to migrate. 5. Once all devices are verified on the 802.1X network, decommission the PSK SSID.

Implementation Notes: This phased approach minimises disruption while achieving the core objectives. Leveraging MDM for laptops provides a zero-touch experience for staff. Segmenting the POS and scanner traffic via dynamic VLAN assignment directly addresses PCI DSS requirements by isolating in-scope systems from general corporate traffic. The temporary quarantine VLAN is a critical risk mitigation step to ensure business continuity during the transition.

A large conference centre wants to offer seamless, secure WiFi to attendees without printing passwords on badges or requiring them to re-enter a captive portal every day. They want to leverage their existing Purple analytics platform. How can they achieve this?

The venue implements a Passpoint (Hotspot 2.0) enabled network infrastructure. 2. They utilise Purple's Connect licence, configuring Purple as the Identity Provider (IdP) for OpenRoaming. 3. When an attendee arrives, if their device already has an OpenRoaming profile (e.g., from their mobile carrier or a previous venue), they connect automatically and securely via EAP-TTLS or EAP-TLS. 4. For users without a profile, they connect to a standard onboarding SSID, authenticate once via the Purple captive portal (providing valuable first-party data), and are prompted to download a secure Passpoint profile. 5. For the remainder of the event, and on subsequent visits, the user connects automatically to the secure network without any passwords.

Implementation Notes: This solution balances security, user experience, and marketing objectives effectively. By utilising Passpoint and OpenRoaming, the venue provides a cellular-like connectivity experience. Integrating Purple as the IdP ensures the venue still captures the necessary analytics and marketing opt-ins during the initial onboarding phase, while eliminating the friction of daily captive portal logins.

Scenario Analysis

Q1. You are deploying EAP-TLS across a university campus. During the pilot phase, several Windows laptops fail to connect, reporting an authentication error. The RADIUS logs show the server rejected the client certificates. The certificates are valid and issued by the correct internal CA. What is the most likely cause, and how do you resolve it?

💡 Hint:Consider the environmental factors that cryptographic certificate validation relies upon, beyond the certificate content itself.

Show Recommended Approach

The most likely cause is Clock Skew. EAP-TLS certificate validation is highly sensitive to time discrepancies. If the system time on the Windows laptops is significantly out of sync with the RADIUS server or the Certificate Authority, the certificates will be deemed invalid even if they are within their stated validity period. Resolution: ensure all devices and infrastructure components are configured to sync with a reliable NTP server. Verify time synchronisation on the RADIUS server, the CA, and the client devices.

Q2. A hospital IT director wants to implement passwordless WiFi for all clinical devices (infusion pumps, mobile workstations) but is concerned about the administrative overhead of managing certificates for thousands of headless devices that cannot use an onboarding portal. What is the recommended approach?

💡 Hint:Think about automated provisioning protocols used by device management systems, and how certificates can be delivered without user interaction.

Show Recommended Approach

The recommended approach is to leverage a Mobile Device Management (MDM) or Unified Endpoint Management (UEM) solution integrated with the hospital's PKI. Using protocols like SCEP (Simple Certificate Enrollment Protocol) or EST (Enrollment over Secure Transport), the MDM can silently request and install unique client certificates onto the clinical devices over the air, requiring zero manual intervention from IT staff or clinicians. The MDM should also be configured to automatically renew certificates before they expire.

Q3. Your organisation is transitioning from a shared PSK network to an 802.1X EAP-TLS network. You plan to run both SSIDs concurrently for one month. However, you want to ensure that users who have successfully migrated to the secure network do not accidentally fall back to the less secure PSK network. How can you configure the infrastructure to prevent this?

💡 Hint:Consider how the RADIUS server can be used to control access on the legacy network, and what information is available to it about devices that have already been provisioned.

Show Recommended Approach

Implement a RADIUS policy on the legacy PSK network that uses MAC Authentication Bypass (MAB) to identify devices. When a device successfully authenticates via EAP-TLS on the new network, its MAC address is recorded in the RADIUS database. The RADIUS policy for the legacy PSK network can then be configured to deny access — or assign to a quarantine VLAN with restricted bandwidth — for any MAC address known to be provisioned for 802.1X. This forces the device to use the secure SSID and prevents accidental fallback.