↪️
ccie.nyquist.eu
  • Table of Contents
  • Layer 2 Technologies
    • Ethernet Switching
      • L2 Switch Operations
      • Spanning Tree
        • 802.1d – STP
        • 802.1w – RSTP
        • 802.1s – MSTP
      • VTP 101
      • Private VLANs
      • VLANs
      • EtherChannel 101
    • Layer 2 WAN Protocols
      • HDLC
        • HDLC 101
      • PPP
        • PPP 101
        • PPP Authentication - PAP
        • PPP Authentication – CHAP
        • PPP Authentication – EAP
        • PPP Multilink
        • PPPoFR – PPP over Frame Relay
        • PPPoE – PPP over Ethernet
      • Frame Relay
        • Frame Relay 101
        • Frame Relay 102
        • Frame Relay Encapsulations – IETF vs Cisco
        • Multilink Frame Relay
        • Frame Relay Switching
        • Routing over Frame Relay
      • Bridging
        • Bridging on a router
        • MTU 101
    • Wireless
      • Wireless Principles
      • Wireless Implementations
      • Wireless Roaming
      • Wireless Authentication
        • WPA2 PSK
        • WPA2 802.1X
  • IPv4
    • IPv4 Addressing
      • Backup Interfaces
      • FHRP 101
      • DHCP 101
      • DNS 101
      • ARP 101
      • IPv4 101
      • Tunnel Interfaces
        • GRE Tunnels
      • BFD – Bidirectional Forwarding Detection
    • IPv4 Routing
      • How the routing table is built
        • How CEF works
        • Routing Order of Operations
        • NSF – Non Stop Forwarding
      • RIP
        • RIP 101
      • EIGRP
        • EIGRP 101
        • EIGRP Metric
        • More EIGRP Features
      • OSPF
        • OSPF 101
        • OSPF Areas
        • OSPF LSAs
        • OSPF Mechanics
      • IS-IS
        • IS-IS 101
        • IS-IS Mechanics – CLNP
      • BGP
        • BGP 101
        • BGP Attributes
        • More BGP
      • Route Redistribution
      • Policy based Routing
      • PfR 101 – Perfromance Routing
      • ODR
  • IPv6
    • IPv6-101
    • IPv6 Routing
    • Interconnecting IPv6 and IPv4
  • MPLS
    • MPLS 101
    • MPLS L3 VPN
  • Multicast
    • Multicast 101
    • PIM 101
    • IGMP 101
    • Inter Domain Multicast
    • IPv6 Multicast
    • Multicast features on switches
  • Security
    • NAT 101
    • NAT for Overlapping Networks
    • ACLs 101
    • ACLs 102
    • Cisco IOS Firewall
    • Zone Based Firewall
    • AAA 101
    • Controlling CLI Access
    • Control Plane
    • Switch Security
      • Switchport Traffic Control
      • Switchport Port Security
      • DHCP Snooping and DAI
      • 802.1x
      • Switch ACLs
    • IPSec VPN 101
      • IKE / ISAKMP 101
      • IPSEC Crypto Maps 101
      • IPSEC VTI 101
      • DMVPN 101
    • EAP 101
  • Network Services
    • NTP 101
    • HTTP 101
    • File Transfer 101 – TFTP & FTP
    • WCCP 101
  • QoS
    • QoS 101
    • Classification and Marking
    • Congestion Management
      • Legacy Congestion Management
      • SPD – Selective Packet Discard
      • CBWFQ
      • IP RTP Priority
    • Congestion Avoidance – WRED
    • Policing and Shaping
      • CAR 101
    • Compression and LFI
      • Header and Payload Compression
      • LFI for MultiLink PPP
    • Frame Relay QoS
      • Per VC Frame Relay QoS
    • RSVP 101
    • Switching QoS
  • Network Optimization
    • NetFlow 101 – TNF – Traditional NetFlow
    • NetFlow 102 – FNF – Flexible NetFlow
    • IP SLA 101
    • IP Accounting 101
    • Logging 101
    • SNMP and RMON 101
    • Cisco CLI Tips and Tricks
    • AutoInstall
    • Enhanced Object Tracking
    • Troubleshooting 101
    • SPAN, RSPAN, ERSPAN
  • Network Architecture
    • Hierarchical Network Architecture
    • SD Access
    • SD WAN
Powered by GitBook
On this page
  • 802.1X
  • PKI and Certificate-Based Authentication

Was this helpful?

  1. Layer 2 Technologies
  2. Wireless
  3. Wireless Authentication

WPA2 802.1X

PreviousWPA2 PSKNextIPv4 Addressing

Last updated 2 years ago

Was this helpful?

802.1X

The 802.1X mechanism is similar to . With Wi-Fi, the 3 roles remain the same:

  • Supplicant: The wireless client

  • Authenticator: The AP

  • Authentication server: The server that manages the access requests (it can run on the same host as the authenticator) - typically RADIUS

In a wireless environment the process is as follows:

  1. The client (suplicant) sends an Authentication Request just like for Open Authentication.

  2. The AP (authenticator) responds with an Authentication Success

  3. The client sends an Association Request

  4. The AP responds with an Association Reponse that includes an ID.

  5. Even though Asscociation is completed, the virtual port is still not allowed to pass any traffic until the 802.1X authentication completes succesfuly. At this step the client can start the process or the authenticator can request the credentials

  6. The AP (authenticator) sends the 802.1X traffic encapsulated to the Authentication server while all other network traffic on that port is dropped. The response from the server is sent to the client (this way the client can also authenticate the server)

  7. On a succesful authentication the virtual port will be allowed to pass data.

One key aspect of 802.1x is that it will authenticate each supplicant independently and during the authentication process the server and the client derive an individual key that will be used by the client in this session. Because keys are different for each client and session based it is hard for an intruder to get access to the network.

PKI and Certificate-Based Authentication

  • The Certificate Authority (CA) is used to generate digital certificates for users (clients) and the Authentication servers in order to validate their identities

  • Clients requests a user certificate from CA and use it to authenticate themseleves to the server using 802.1X

  • Servers request a server certificate from CA or it can use a self-signed certificate when it acts as its own CA

  • WLCs that are used as the authentication servers use preinstalled certi

802.1X for wired networks