Appendix D Wireless LANs
P-870H/HW Series User’s Guide
308
• Access-Challenge
Sent by a RADIUS server requesting more information in order to allow access.
The access point sends a proper response from the user and then sends another
Access-Request message.
The following types of RADIUS messages are exchanged between the access point
and the RADIUS server for user accounting:
• Accounting-Request
Sent by the access point requesting accounting.
• Accounting-Response
Sent by the RADIUS server to indicate that it has started or stopped accounting.
In order to ensure network security, the access point and the RADIUS server use a
shared secret key, which is a password, they both know. The key is not sent over
the network. In addition to the shared key, password information exchanged is
also encrypted to protect the network from unauthorized access.
Types of EAP Authentication
This section discusses some popular authentication types: EAP-MD5, EAP-TLS,
EAP-TTLS, PEAP and LEAP. Your wireless LAN device may not support all
authentication types.
EAP (Extensible Authentication Protocol) is an authentication protocol that runs on
top of the IEEE 802.1x transport mechanism in order to support multiple types of
user authentication. By using EAP to interact with an EAP-compatible RADIUS
server, an access point helps a wireless station and a RADIUS server perform
authentication.
The type of authentication you use depends on the RADIUS server and an
intermediary AP(s) that supports IEEE 802.1x. .
For EAP-TLS authentication type, you must first have a wired connection to the
network and obtain the certificate(s) from a certificate authority (CA). A certificate
(also called digital IDs) can be used to authenticate users and a CA issues
certificates and guarantees the identity of each certificate owner.
EAP-MD5 (Message-Digest Algorithm 5)
MD5 authentication is the simplest one-way authentication method. The
authentication server sends a challenge to the wireless client. The wireless client
‘proves’ that it knows the password by encrypting the password with the challenge
and sends back the information. Password is not sent in plain text.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
