Appendix D Wireless LANs
VMG1312-B Series User’s Guide
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password- guessing at t acks but it ’s st ill an im provem ent over WEP as it em ploys a consist ent ,
single, alphanum eric password t o derive a PMK which is used t o generat e unique t em poral
encrypt ion keys. This prevent all wireless devices sharing t he sam e encrypt ion keys. ( a weakness of
WEP)
User Authentication
WPA and WPA2 apply I EEE 802.1x and Ext ensible Aut hent icat ion Prot ocol ( EAP) t o aut hent icat e
wireless client s using an ext ernal RADI US dat abase. WPA2 reduces t he num ber of key exchange
m essages from six t o four ( CCMP 4- way handshake) and short ens t he t im e required t o connect t o a
net work. Ot her WPA2 aut hent icat ion feat ures t hat are different from WPA include key caching and
pre- aut hent icat ion. These t wo feat ures are opt ional and m ay not be support ed in all wireless
devices.
Key caching allows a wireless client t o st ore t he PMK it derived t hrough a successful aut hent icat ion
wit h an AP. The wireless client uses t he PMK when it t ries t o connect t o t he sam e AP and does not
need t o go wit h t he aut hent icat ion process again.
Pre- aut hent icat ion enables fast roam ing by allowing t he wireless client ( already connect ing t o an
AP) t o perform I EEE 802.1x aut hent icat ion w it h anot her AP before connect ing t o it .
Wireless Client WPA Supplicants
A wireless client supplicant is t he soft ware t hat runs on an operat ing syst em inst ruct ing t he wireless
client how t o use WPA. At t he t im e of writ ing, t he m ost widely available supplicant is t he
WPA pat ch
for Window s XP, Funk Soft ware's Odyssey client .
The Windows XP pat ch is a free download t hat adds WPA capabilit y t o Windows XP's built- in " Zero
Configurat ion" wireless client . However, you m ust run Windows XP t o use it .
WPA(2) with RADIUS Application Example
To set up WPA( 2) , you need t he I P address of t he RADI US server, it s port num ber ( default is 1812) ,
and t he RADI US shared secret . A WPA( 2) applicat ion exam ple wit h an ext ernal RADI US server
looks as follows. " A" is t he RADI US server. " DS" is t he dist ribut ion syst em .
1
The AP passes t he wireless client 's aut hent icat ion request t o t he RADI US server.
2
The RADI US server t hen checks t he user's ident ificat ion against it s dat abase and grant s or denies
net work access accordingly.
3
A 256- bit Pairwise Mast er Key ( PMK) is derived from t he aut hent icat ion process by t he RADI US
server and t he client .
Summary of Contents for VMG1312-B Series
Page 4: ...Contents Overview VMG1312 B Series User s Guide 4 Troubleshooting 289 ...
Page 14: ...Table of Contents VMG1312 B Series User s Guide 14 ...
Page 15: ...15 PART I User s Guide ...
Page 16: ...16 ...
Page 30: ...Chapter 2 The Web Configurator VMG1312 B Series User s Guide 30 ...
Page 35: ...Chapter 4 Tutorials VMG1312 B Series User s Guide 35 7 Click Apply to save your settings ...
Page 77: ...77 PART II Technical Reference ...
Page 78: ...78 ...
Page 166: ...Chapter 9 Routing VMG1312 B Series User s Guide 166 ...
Page 184: ...Chapter 10 Quality of Service QoS VMG1312 B Series User s Guide 184 ...
Page 210: ...Chapter 13 Interface Group VMG1312 B Series User s Guide 210 ...
Page 226: ...Chapter 15 Firewall VMG1312 B Series User s Guide 226 ...
Page 232: ...Chapter 17 Parental Control VMG1312 B Series User s Guide 232 ...
Page 242: ...Chapter 19 Certificates VMG1312 B Series User s Guide 242 ...
Page 246: ...Chapter 20 Log VMG1312 B Series User s Guide 246 ...
Page 250: ...Chapter 21 Traffic Status VMG1312 B Series User s Guide 250 ...
Page 256: ...Chapter 24 IGMP Status VMG1312 B Series User s Guide 256 ...
Page 260: ...Chapter 25 xDSL Statistics VMG1312 B Series User s Guide 260 ...
Page 262: ...Chapter 26 User Account VMG1312 B Series User s Guide 262 ...
Page 268: ...Chapter 29 TR 064 VMG1312 B Series User s Guide 268 ...
Page 272: ...Chapter 30 Time Settings VMG1312 B Series User s Guide 272 ...
Page 278: ...Chapter 32 Logs Setting VMG1312 B Series User s Guide 278 ...
Page 296: ...Chapter 36 Troubleshooting VMG1312 B Series User s Guide 296 ...
Page 336: ...Appendix C Pop up Windows JavaScripts and Java Permissions VMG1312 B Series User s Guide 336 ...
Page 350: ...Appendix D Wireless LANs VMG1312 B Series User s Guide 350 ...
Page 374: ...VMG1312 B Series User s Guide 374 Index ...