Инструкция для ZYXEL P-334 EE

(скачивание инструкции бесплатно)
Формат файла: PDF
Доступность: Бесплатно как и все руководства на сайте. Без регистрации и SMS.
Дополнительно: Чтение инструкции онлайн
background image

Prestige 334 User’s Guide

Chapter 11 Firewall

126

C

H A P T E R

11

Firewall

This chapter gives some background information on firewalls and explains how to get started 
with the Prestige firewall.

11.1  Introduction

11.1.1  What is a Firewall?

Originally, the term 

firewall

 referred to a construction technique designed to prevent the 

spread of fire from one room to another. The networking term "firewall" is a system or group 
of systems that enforces an access-control policy between two networks. It may also be 
defined as a mechanism used to protect a trusted network from an untrusted network. Of 
course, firewalls cannot solve every security problem. A firewall is one of the mechanisms 
used to establish a network security perimeter in support of a network security policy. It 
should never be the only mechanism or method employed. For a firewall to guard effectively, 
you must design and deploy it appropriately. This requires integrating the firewall into a broad 
information-security policy. In addition, specific policies must be implemented within the 
firewall itself. 

11.1.2  Stateful Inspection Firewall. 

Stateful inspection firewalls restrict access by screening data packets against defined access 
rules. They make access control decisions based on IP address and protocol. They also 
"inspect" the session data to assure the integrity of the connection and to adapt to dynamic 
protocols. These firewalls generally provide the best speed and transparency; however, they 
may lack the granular application level access control or caching that some proxies support. 
Firewalls, of one type or another, have become an integral part of standard security solutions 
for enterprises.

11.1.3  About the Prestige Firewall

The Prestige firewall is a stateful inspection firewall and is designed to protect against Denial 
of Service attacks when activated (click

 FIREWALL

 and then click the 

Enable

 

Firewall 

check box). The Prestige's purpose is to allow a private Local Area Network (LAN) to be 
securely connected to the Internet. The Prestige can be used to prevent theft, destruction and 
modification of data, as well as log events, which may be important to the security of your 
network. 

The Prestige is installed between the LAN and a broadband modem connecting to the Internet. 
This allows it to act as a secure gateway for all data passing between the Internet and the LAN.

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
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
Оглавление инструкции

Document Outline