IEEE 802.1xIEEE 802.11i

N9490012 2006/12/23

J.-C. Chen et al.Wireless LAN Security and IEEE 802.11i2004

WLANIEK-ITIS

IEK-ITIS

IEEE 802.11(b)IEEE 802.11(b)MAC

WEP(Wired Equivalent Privacy)

(client)(access point, AP)clientAP

(access control)

IEEE 802.11(b)WEPRC4IEEE

RC4,(WLAN ClientAccess Point)Key,Key

,RC4,24 bitsIV(initial vector, IV),IVWEP KeyRC4,Stream CipherXOR,,IV,IVWEP Key,

WEP Key24 bitsIVIVIV24bitsIV2^24(16777216)WEP Key2^24IV

IV(PCMCIA)IV

WEPWEP Key

share keyIEEE IEEE 802.1xWLANIEEE 802.11i

802.1xMAC 802.1xIP

802.1xIEEE 802.11(b)IEEE 802.1x

IEEE 802.1x EAPOL(EAP Over Lan)Authentication (AAA )

EAPOL(EAP Over Lan)IP Layer, EAP,EAPOL,Access PointAAA (Authentication, Authorization, and Accounting) Server.

Authentication Authentication

AAA IETF(The Internet Engineering TaskForce)RFC 2903RFC 2904RFC 2905RFC 2906RFC 2989

AAA RADIUS(Remote Authentication Dial In User Service)Diameter3GPP2 CDMA 2000 Diameter CDMA 2000

CISCO TACACS+(TerminalAccess Controller Access Control System)

RADIUSRequestResponseAccept Reject

Access RequestRADIUS

IEEE 802.1x

1. (Password base) 2. (Certificate base) 3. SIM(SIM card base)

EAP-MD5EAP-TLSEAP-SIM1,2EAP-TTLS

EAP-MD5 MD5

EAP EAP Authenticator (Identity)AuthenticatorAuthenticator AuthenticatorAuthenticator Authenticator AP

EAP-TLSMicroSoftCisco(PKI,Public Key Infrastructure)PKIPKI

EAP EAP Authenticator Authenticator Authenticator EAP-TLS TLS TLS EAP TLS TLS EAP-TLS WAP-TLS Authenticator Authenticator Authenticator

IETFIEEE 802.1X RADIUS Usage Guidelines802.1x RadiusAAAWEP KeyAccess PointWEP KeyWEP Key802.1xWEP KeyEAPOL-KeyWEP KeyWEP KeyWEP Key

802.1xWEP KeyHandshakingWEP KeyAccess PointWEP KeyWEP KeyKeyWEP Key

IEEE 802.11iIEEE 802.11iWIFIWIFI Protected AccessIEEE 802.11i Draft

802.11iTKIP (Temporal Key Integrity Protocol)AESTKIPWPA 1.x (WPA/SSN)

IEEE 802.11i

TKIP802.11RC4Key

WEP24-bitIVTKIP48-bit IVIVWPA802.1xEAPWPA TKIPWEPWPAWPAAESWPA TKIPWEPWEP KeyWPA TKIPKey

TKIP Per-Packet

TKIPRC4KeyTKIP128-bits WEP Key KeyWEP KeyWEP KeyIV RC4 KeyTKIPTKIP KeyIV128 bitsIV128 bits Key

48 bits IV(32 bits16 bits)Phase 1Phase 2Key

802.11i WPA

MIC

KeyWPAMIC(MessageIntegrity Code) MICCRC

MICMichael64 bitsMICMichaelMIC

IEEE 802.11iIEEE 802.1xTKIPAESTKIPRC4AESReal-Time

2002Wi-FiWPA(Wi-Fi Protected Access)WPATKIPWPAWPAIntersilAtherosAtmelAgereEnvaraIEEE 802.11iTKIPAES