ZyXEL Communications VMG1312-B Series User Manual page 342

Appendix D Wireless LANs
IEEE 802.1x
I n June 2001, t he I EEE 802.1x st andard was designed t o ext end t he feat ures of I EEE 802.11 t o
support ext ended aut hent icat ion as well as providing addit ional account ing and cont rol feat ures. I t
is support ed by Windows XP and a num ber of net work devices. Som e advant ages of I EEE 802.1x
are:
• User based ident ificat ion t hat allows for roam ing.
• Support for RADI US ( Rem ot e Aut hent icat ion Dial I n User Service, RFC 2138, 2139) for
cent ralized user profile and account ing m anagem ent on a net work RADI US server.
• Support for EAP ( Ext ensible Aut hent icat ion Prot ocol, RFC 2486) t hat allows addit ional
aut hent icat ion m et hods t o be deployed wit h no changes t o t he access point or t he wireless
client s.
RADIUS
RADI US is based on a client- server m odel t hat support s aut hent icat ion, aut horizat ion and
account ing. The access point is t he client and t he server is t he RADI US server. The RADI US server
handles t he following t asks:
• Aut hent icat ion
Det erm ines t he ident it y of t he users.
• Aut horizat ion
Det erm ines t he net work services available t o aut hent icat ed users once t hey are connect ed t o t he
net work.
• Account ing
Keeps t rack of t he client 's net work act ivit y.
RADI US is a sim ple package exchange in which your AP act s as a m essage relay bet ween t he
wireless client and t he net work RADI US server.
Types of RADIUS Messages
The following t ypes of RADI US m essages are exchanged bet ween t he access point and t he RADI US
server for user aut hent icat ion:
• Access- Request
Sent by an access point request ing aut hent icat ion.
• Access- Rej ect
Sent by a RADI US server rej ect ing access.
• Access-Accept
Sent by a RADI US server allowing access.
• Access- Challenge
Sent by a RADI US server request ing m ore inform at ion in order t o allow access. The access point
sends a proper response from t he user and t hen sends anot her Access- Request m essage.
The following t ypes of RADI US m essages are exchanged bet ween t he access point and t he RADI US
server for user account ing:
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VMG1312-B Series User's Guide