Беспроводные сети wi fi

2

.................................................................................................................................... 4 1. ......................................................... 6

1.1 Wi-Fi? ................................................................................................................ 61.2 .................................................................................................. 71.3 ........................................................... 8

1.3.1 ......................................................................... 81.3.2 ...................................................................................................... 111.3.3 ................................................................................................ 121.3.4 ............................................................................. 161.3.5 .................................................... 161.3.6 ......................................................................... 191.3.7 ........................................................................... 23

1.4 IEEE 802.11 ................................................................................................ 261.4.1 IEEE 802.11 .................................................................................. 271.4.2 802.11 ............................................................ 271.4.3 MAC- .............................................................................................. 32

1.5 IEEE 802.11 ................................................................................................... 361.5.1 IEEE 802.11 ................................................................................................................ 381.5.2 IEEE 802.11b .............................................................................................................. 411.5.3 IEEE 802.11 .............................................................................................................. 451.5.4 IEEE 802.11g .............................................................................................................. 47

1.6 ........................................................................ 501.6.1 Ad Hoc ........................................................................................................... 501.6.2 ...................................................................................... 561.6.3 WDS WDS WITH AP .............................................................................. 591.6.4 ................................................................................................... 671.6.5 .......................................................................................................... 68

1.7 ...................................................... 691.7.1 ............................................................................................................. 691.7.2 ......................................................................... 75

1.8 WiMAX ................................................................................ 771.8.1 WiMAX ............................................................................................. 771.8.2 ..................................................................................................... 781.8.3 ......................................................................................................... 80

2. ..................................................... 852.1 ..................................................... 852.2 ..................................................................................................... 89

2.2.1 ....................................................................... 892.2.2 ............................................................................................................ 89

2.3 ............................................................ 932.3.1 WEP ................................................................................... 942.3.2 WEP ................................................................................ 98

2.4 ...................................................................... 1032.4.1 IEEE 802.11 .............................. 1032.4.2 802.11 ................................................ 1072.4.3 WPA ............................................................................................... 1092.4.4 802.11i (WPA2) .......................... 1142.4.5 802.1x/EAP (Enterprise-) ............................................................. 116

2.5 ............... 1252.5.1 .............................................. 125

3

2.5.2 .......................................................... 1282.6 ........................................... 129

3. .............................................................................................................. 1343.1 ................................................................................................... 134

3.1.1 ................................................................................... 1343.1.2 ............................................................................................... 1353.1.3 .......................................................................... 135

3.2 .............................................................................................. 1373.2.1 ..................................................................... 1373.2.2 ..................................... 137

3.3 ........................................... 1383.3.1 ................................................................................................................. 1383.3.2 ........................................................................ 1393.3.3 .......................................................................................................................... 1393.3.4 ..................................................................................... 140

3.4 / ................................................ 1403.5 ...................................................................................... 142

3.5.1 ...................................... 1423.5.2 .............................................................................................. 144

3.6 - ... 1453.6.1 - ............................................................... 1453.6.2 - ........................................................................ 1503.6.3 , ........................................... 151

. D-Link ......................................... 153 . ............................... 165 . D-Link ................................................................................ 169 ............................................................................................................................. 174 .............................................................................................. 178

4

XIX

20- . 30- . 70- . , 80- GSM, , , , . 90-x . . , .

, CDMA (Code Division Multiple Access, ), GSM (Global for Mobile Communications, ), TDMA (Time Division Multiple Access, ), 802.11, WAP (Wireless Application Protocol, ), 3G ( ), GPRS (General Packet Radio Service, ), Bluetooth ( , , ), EDGE (Enhanced Data Rates for GSM Evolution, GSM), i-mode .. , .

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1.6 1.6.1 AD HOC

Ad Hoc (. 1.34) . -, . , .

51

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.

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(PCI, PCMCI, ExpressCard ..) .

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52

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1 (.1.34), . : Windows XP Windows Vista D-Link AirPlus XtremeG Wireless Utility, D-Link.

1) Windows. , Windows,

. Windows (. 1.36)

53

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IP-.

, , (TCP/IP) (. 1.37)

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(1): 192.168.0.2, : 255.255.255.0.

54

Ad Hoc, (. 1.35) Windows. , , (. 1.38). SSID (, AdHocNet) . .

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Windows (. 1.38), (AdHocNet). , Ad Hoc. , , . . 2) D-Link AirPlus XtremeG

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55

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56

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57

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58

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59

1.6.3 WDS WDS WITH AP

WDS (Wireless Distribution System) . , . . , , , . uplink- (. 1.44).

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60

. 1.45 ,

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61

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AP , 15-20 . WDS-, uplink-.

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62

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63

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64

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65

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66

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67

. 1.53

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68

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73

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74

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75

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76

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77

, .

, . . 1.8 WIMAX 1.8.1 WIMAX

: , . WiMAX (Worldwide Interoperability for Microwave Access), IEEE 802.16.

WiMAX WiMAX-: http://www.wimaxforum.org IEEE 802.16, 1999 . , Nokia, Harris Corporation, Ensemble, Crosspan Aperto. 2005 230 . (World Summit on Information Society, WSIS) , WiMAX:

1) WiMAX , , , , 1,5 100 .

2) WiMAX , , 2005 960 . , 14,5 .

WiMAX , ( , , ) - . , :

1) (xDSL ), WiMAX - , , () .

2) ( ), ( ), , , .

3) , , , .

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78

5) . . WiMAX OFDM , .

6) WiMAX IP, .

7) WiMAX , .

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1) WiMAX, : .

2) WiMAX: (. 1.64).

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, WiMAX - , : , .

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79

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80

IEEE 802.16 : , 50 , . , . . Ethernet-, , 802.11 Wi-Fi Ethernet.

WiMAX. , . 1.8.3

802.16e-2005 .

1) Fixed WiMAX - ; 2) Nomadic WiMAX - ; 3) Portable WiMAX - ; 4) Mobile WiMAX - . .

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(xDSL, T1, ..). 10-66 . - (. 1.66).

81

. 1.66

, - . ( - 25 28 ), 120 /. 802.16d-2004 . , Fixed WiMAX, WiMAX.

Nomadic WiMAX () Fixed

WiMAX. WiMAX, , . , , , . , .

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82

( , , , , ..).

. 1.67

WiMAX (. 1.67). 2006 , WiMAX. , 2008 .

Mobile WiMAX 802.16e-2005

120 /. :

1) . 2) . 3) Time Division Duplex (TDD),

.

4) Hybrid-Automatic Repeat Request (H-ARQ), .

5) .

83

6) .

7) Network-Optimized Hard Handoff (HHO), 50 .

8) Multicast and Broadcast Service (MBS), DVB-H, MediaFLO 3GPP E-UTRA :

; ; ; .

9) Smart Antenna, , , , - , ().

10) Fractional Frequency Reuse, / .

11) 5 ( , ).

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, , - Fixed WiMAX. , , ( , ) .

WiMAX- , , , . Mobile WiMAX , , , : WiMAX-, .

, - , . ( ) , . , , .

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84

, , , - WiBro. , . , WiMAX, WiBro. , WiMAX-, . , - , .

, . Mobile WiMAX, . 802.16f (Full Mobile WiMAX) 802.16m.

. 1 / 100 /. 2008 2009 , .

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85

2. 2.1

. . . , , , . , , , , , .

, , . , 2.1.

. 2.1

, , , . , . , . .

86

, . , , , , . , . , , . , . , , , .

. Address Resolution Protocol (ARP). . MITM (man in the middle, ) . . MITM , : . . , , . , , .

ARP-, , , . .

, ( ). (Denial of Service, DOS)

DOS. , , , (. 2.2). . , . DOS . , .

87

. 2.2

, , , . .

, 2.3. , . , .

. 2.3

, 2.4. .

. 2.4

, . , , , . ,

88

, . , .

. .

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, , . ( , ). , . , , , . .

. , , . .

- . , , . , , , . , , .

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89

802.11 , . , . 2.2 2.2.1 : , ( , , , . .). : . : , . : , , , . : . : , , . : , / ; ; . : , / ; ; . : , . -: , ( ). , , . : , -. (Message digest): , - ( , ). : . : , ( ), . AAA (Authentication, Authorization, Accounting): , . VPN (Virtual Private Networks): . IDS (Intrusion Detection System): . 2.2.2

. , .

. , , , , . ( ) ().

90

, : , -.

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. 2.5

, Data Encryption Standard (DES), 3DES ( DES) International Data Encryption Algorithm (IDEA). 64 . 64 ( ), 64 , - . , , :

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(firmware). , . :

, ;

.

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91

. 2.6

: ; ; . /

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- , , , . (-), (. 2.7). ( ). - .

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92

, . 2.8.

. 2.8

. - .

, . X.509, :

; ; ; ; ; ; .

93

. 2.9

, , (Certification authority, CA), , . (. 2.9):

1) , ; 2) ; 3) ; 4) ; 5)

.

CA . PKI (Public Key Infrastructure). PKI , , , -.

PKI , . PKI , , , - , .

PKI , , . , , , . 2.3

94

, : , . (, , , , ..) .

, , . , , . 2.3.1 WEP

WEP (Wired Equivalent Privacy, ) RC4 (Rivests Cipher v.4, ), . , .

. , . , . , .

RC4 , . n . , n = 8, . . RC4 2n , . S-, S. 2n . i j.

RC4 . , Key, l .

S, . S, , S . 1) : for i = 0 to 2n 1 { S[i] = i j = 0 } 2) : for i = 0 to 2n 1 { j = j + S[i] + Key[i mod l] (S[i], S[j]) }

95

RC4 , S, S . RC4 n- K , . 3) : i = 0 j = 0 4) : i = i + 1 j = j + S[i] (S[i], S[j])

: K = S[S[i] + S[j]].

WEP-: ,

, ;

. , ;

: WEP ; ; WEP-

IEEE 802.11.

.

2 ( , XOR) , , . , , (. 2.10).

. 2.10

, . , XOR .

96

, (. 2.11). , 16- 38 16 1 6 , 10 .

. 2.11

(ECB). ECB , . , , , .

: 1) (Initialization Vectors, IVs) 2) (feedback modes)

40- 104- , . (IV). (Initialization Vector, IV)

. , , IV. . 2.12 , , .

97

. 2.12 WEP

IEEE 802.11 , . , , , .

24 40- 104- WEP, , 64- 128- . , , . , WEP 64 128 , 40 104 . 40- 5 ASCII- (58=40) 10 (104=40), 104- 13 ASCII- (138=104) 26 (264=104). 128- .

. . , (CBC).

XOR . , . . 2.13.

98

. 2.13 2.3.2 WEP

WEP : .

2001 ., . . (Fluhrer S., Mantin I., Shamir A.) , WEP , . WEP (Key Scheduling Algorithm, KSA) RC4. ( ) , .

AT&T/Rice University AirSnort 40 104 4 . 4 , .

WEP , .

99

WEP , .

WEP . , 2 (XOR) . .

, IEEE 802.11, (Message Intgrity Check, MIC). . , ICV (Integrity Check Value), , CRC32 (32-bit Cyclical Redundancy Check, 32- ), . , : (IV Replay) (Bit-Flipping).

1) (Initialization Vector Replay Attacks)

, , . 2.14.

100

. 2.14

1. (, IP-, , ..).

2. , .

3. , XOR .

4. , , .

, , , WEP.

, , , . 2.15.

101

. 2.15

1. , . ICMP (Internet Control Message Protocol, ), ping, , .

2. . 3. 256

ASCII-. 4.

, , ICMP.

5. , .

2) (Bit-Flipping Attacks) ,

, ICV. , .

2- () OSI (Open Systems Interconnection) 3- () . . 2.16.

1. 802.11.

2. 3- .

3. ICV ( ).

4. . 5. ( )

ICV .

102

6. ICV .

7. , . 8.

. 9. ,

. 10.

. 11.

. 12. ,

, .

. 2.16

ICV . ICV , (. 2.17):

1. F1 C1. 2. F2 , F1,

F1. 3. F3 XOR F1

F2. 4. 2 F3. 5. C3 F3 XOR

C1 C2.

103

. 2.17 WEP

IEEE 802.11 . , WEP , . IEEE 802.11 , , , . . D-Link . .

, , , / . . 2.4

IEE 802.11, WPA, WPA2 802.1x. .

2.4.1 IEEE 802.11

IEEE 802.11 (Tradition Security Network, TSN) : (Open Authentication)

104

(Shared Key Authentication). 802.11, (Service Set Identifier, SSID) MAC- (MAC Address Authentication).

(SSID) , . , SSID , . SSID , . , , , SSID. IEEE 802.11

IEEE 802.11 , . IEEE 802.11 (. 2.18):

1. (Client) Probe Request . 2. (Access Point, AP),

, Probe Response. 3.

(Authentication Request).

4. (Authentication Reply).

5. (Association Request).

6. (Association Response).

7. .

. 2.18 802.11

, Probe Request. Probe Request , , SSID . Probe Request Probe Response,

105

. , , . , , .

, , . . , , , 1997 IEEE 802.11 . , IEEE 802.11- ( - . .), , .

: (Authentication Request); (Authentication Response). ,

. , , SSID , . WEP . WEP-, , , (. 2.19).

. 2.19

IEEE 802.11. WEP. . 2.20:

1. , .

106

2. , Challenge Text.

3. Challenge Text WEP-, .

4. Challenge Text, , .

. 2.20 MAC-

MAC- IEEE 802.11, , D-Link. MAC- MAC- , (. 2.21). MAC- IEEE 802.11 .

. 2.21

2.1: WEP-. 1. , , SSID, ,

1.4. Authentication () Shared Key ( ) (. 2.22).

107

. 2.22

2.

WEP, Encryption () Enable. 3. (Key Type) (Key Size). 4. , Valid Key

( ). 64- ASCII 5- , pass1.

, , , , .

2.4.2 802.11

SSID Beacon , , . . , SSID 802.11, Sniffer Pro Wireless. , D-Link, SSID Beacon. SSID Probe Response, . SSID . , SSID

108

.

, . , WEP.

D-Link WEP. , WEP (, ), -.

WEP- Challenge Text, . Challenge . , Challenge Text, , , (Man in the middle Attack). Challenge Text, Challenge Text, (. 2.23). WEP XOR , (Cipher-Text). , XOR . , .

. 2.23

109

MAC-

IEEE 802.11 MAC- . , MAC-, MAC- . MAC- , MAC-. IEEE 802.11 MAC- . 2.4.3 WPA

2001 . 802.11 IEEE 802.11e, . 802.11i 802.11, , .

Wi-Fi- WECA (Wireless Ethernet Compatibility Alliance), Wi-Fi Alliance, IEEE 802.11i, IEEE 2002 . Wi-Fi Protected Access (WPA), .

WPA , WEP. WEP 802.11i , .

IEEE (Temporal Key Integrity Protocol, TKIP).

, TKIP: . WEP ,

; .

;

.

, WEP, IV (Initialization Vectors), , AirSnort, , , IV. WEP-, , , .

IEEE , (per-frame keying). , , , IV, MAC- WEP- . 104- WEP- 24- IV.

110

IEEE 24- 48-- IV.

. 2.24 48- IV , IV .

. 2.24 48- IV

(. 2.25): 1) WEP- 32 48- IV

(32- 0-4 294 967 295) MAC- . 1- . 1- .

2) 1- IV MAC- .

3) (IV), , 16 (16- 0-65 535). 8 ( 24- IV) , .

4) WEP- . 5) 16- IV , 1-

32 1. 6) , 2.

111

. 2.25 WPA

. IV, 0. -

000000000000000000000000000000000000000000000000. 32 IV ( 32 )

WEP- (, 128- ) MAC- ( 48- ) 1- (80- ).

1- () 32 IV MAC- , 128- , 16 IV (16 ).

1. IV , IV 1- (32 ) 1 ( 31 , 00000000000000000000000000000001) ..

WEP , . -, ( TKIP ) WEP 802.11. , .

, (ICV) 802.11, (MIC). MIC , .. IEEE , Michael (), ICV 802.11.

MIC , , . MAC- MAC- , . . 2.26 Michael MIC.

112

. 2.26

TKIP :

1) - (. 2.27).

2) MIC MIC . 3) MAC

. 4) . 5) .

113

. 2.27 TKIP

TKIP,

(. 2.28). 1) 1- . 2) IV, WEP,

2- . 3) IV , , . 4) -

(ICV). 5) ,

. 6) ,

. 7) MIC ,

MIC . 8) , . 9) , , MIC

MIC.

. 2.28 TKIP

MIC : 1) . 2) . 3) , ,

60 , . 4) .

WPA : Enterprise () Pre-Shared Key ().

114

, 802.1x , RADIUS (Remote Authentication Dial-In User Service). Enterprise- .

WPA , .. , . WPA-PSK ( , , , ). , . , WPA-PSK , WEP, - .

, WPA/TKIP , WEP , 802.11 .

MIC MIC. , . , Enterprise-, 802.11i . 2.4.4 802.11I (WPA2)

2004 . IEEE 802.11i.

, WPA . WEP, , Wi-Fi-. WPA , .

WPA, , . RC4 TKIP. , - .

, WEP, . . 802.11i, WPA2 Wi-Fi Alliance.

802.11i (Robust Security Network, RSN), , . , .. , RSN, WEP. RSN, WEP ( WPA/TKIP , ), WEP .

802.11i TKIP, RSN AES (Advanced Encryption Standard) CCMP (Counter Mode CBC MAC Protocol) , , .

115

RSN AES , , RC4 WPA. , WEP. AES , 128 . CCMP, , , AES. TKIP WPA. CCMP MIC, Cipher Block Chaining Message Authentication Code (CBC-MAC). .

WEP . . WEP ( ), .

RSN , TKIP. AES/CCMP, , 512 , TKIP. - , . , -. 128- , (128 ). , - . , , WPA.

802.11i (WPA2) , , , .

802.11i . , . , 802.11i , ; . , , WPA , , , RSN.

, , 5-20% WEP, WPA. , AES TKIP, - . , WPA2- .

WPA2, WPA, : Enterprise () Pre-Shared Key ().

2.2:

WPA2-PSK.

1. , , SSID, , 1.4. Authentication () WPA2-PSK (. 2.29).

116

. 2.29

2. (Cipher Type). : AUTO,

TKIP, AES. AUTO, .

3. (Group Key Update Interval), .

4. PassPhrase , 8 , secretpass.

, , , , .

2.4.5 802.1X/EAP (ENTERPRISE-)

, 802.11 . , :

1) ; 2) ; 3) .

IEEE 802.1x IEEE 802.1x .

117

Extensible Authentication Protocol EAP ( ) . IEEE 802.1x

IEEE 802.1x (. 2.30):

(Supplicant) ; (Authenticator)

; (Authentication Server) RADIUS-.

. 2.30 IEEE 802.1x

IEEE 802.1x . .

, , . . , .

118

, 802.1x Ethernet. , , , . RADIUS-, , RADIUS, LDAP, NDS Windows Active Directory. , .

( ). , . IEEE 802.1x, . ( ) EAP Start ( EAP) (. 2.31) .

EAP Request Identity ( EAP) (Identity). EAP Response ( EAP), , .

. 2.31 802.1x/EAP

RADIUS-ACCEPT () RADIUS-REJECT () . RADIUS-ACCEPT , .

119

802.1x , .

802.11 , . , , , . WPA - (Master Key). . 2.32 .

. 1) (

-, PMK, . Pairwise Master Key), 802.1x.

2) , (Authenticator Nonce, ANonce), EAPoL-Key 802.1x.

3) , (Supplicant Nonce, SNonce).

4) (Pairwise Transient Key, PTK) PMK, SNonce, ANonce, MAC- , MAC- . MAC- , MAC- MAC- . , MAC- (. 2.33).

5) (Pseudo Random Function, PRF), 512- PTK.

6) SNonce, 3, EAPoL-Key 802.1x, EAPoL-Key MIC.

7) SNonce PTK , .

8) EAPoL-Key MIC - .

9) EAPoL-Key, , PTK ANonce, EAPoL-Key MIC. , ANonce, 2, .

10) EAPoL-Key, EAPoL-Key MIC, , .

120

. 2.32

. 2.33

121

- (PMK) (PTK)

. , . , . ( BSS, ) , , .

. - (Group Master Key, GMK) . GMK PRF, 256- GMK. PRF-256 ( Nonce), , MAC- (NTP). . 2.34 .

. 2.34

-, , MAC- GNonce (, ) PRF, 256- (Group Transient Key, GTK). GTK 128- - / , 64- MIC (transmit MIC key) 64- MIC (MIC receive key).

, , - (PMK).

EAPoL-Key. EAPoL, . , - - BSS. MIC, , .

122

, , RADIUS- . ( ). , WEP.

802.11 , . , .

802.1x EAP, (IETF). EAP CHAP (Challenge Handshake Authentication Protocol, ), (Point to Point Protocol, -), . EAPOL , 802.3, 802.5 802.11. , 802.1x, 2.35.

EAP , (authentication, authorization, and accounting, AAA), . AAA- ( AAA, ), EAP, , . , . .

. 2.35 802.1x/EAP

, -. , . , , :

EAP-MD5 , 802.1x, . CHAP.

123

EAP-MD5 . -, . , , . , , ;

EAP-TLS (EAP-Transport Layer Security, ) . EAP-TLS SSLv3 . TLS SSL PKI (Public Key Infrastructure): . AAA- . PKI. RADIUS- EAP-TLS. 802.1x/EAP, . EAP-TLS (. 2.36):

. 2.36 EAP-TLS

EAP-LEAP (Lightweight , EAP) Cisco , Cisco. LEAP ( ) 802.1x, . LEAP Free-RADIUS, , . , , . , EAP-LEAP , .

124

, .

PEAP (Protected , EAP) EAP-TTLS (Tunneled Transport Layer Security , EAP), Certicom and Funk Software. , , D-link. EAP-TTLS , , , . EAP-TTLS , PAP, CHAP, MS-CHAP, MS-CHAPv2 EAP-MD5. , EAP-TTLS TLS , . EAP-TTLS Odyssey Funk Software. EAP-TTLS, CHAP. PEAP-MS-CHAPv2 PEAP-EAP-TLS, . D-link, Windows XP Service Pack 2. (.2.37):

. 2.37 PEAP

EAP-SIM - SIM USIM.

125

IETF GSM, 802.11. , EAP-SIM .

, 802.1x 2.38.

. 2.38 802.1x

WPA WPA2. 2.5

2.5.1

(Virtual Private Network, VPN) ,

, . 802.11 , VPN , .

, . - . VPN, , 802.11i RADIUS- .

(PSK) 802.1x . VPN , . VPN , . .

VPN , . VPN , , (Layer Two Tunneling

126

Protocol, L2TP). , , , , , . , . , (-, , ) .

VPN : , . , VPN DoS- DDoS- .

VPN, , , , , . , WEP . VPN , . , , - . VPN . VPN , .

VPN, -, - -. -

VPN- (. 2.39).

127

. 2.39 -

VPN , , .

, , VPN- . , RFC 1918 , . .

. , , . , WEP TKIP , , , . -

.

, VPN-. . VPN.

128

VPN -, , VPN - . . -

, -, . , . VPN. , . , . , VPN - (Ad Hoc) . 2.5.2 IPSec

IPSec , VPN. . IPSec , , IP. ( 3) OSI , IP. , , IPSec, , IP-. ( 2) , , IP.

IPSec : (Authentication Header, ); (Encapsulating Security Payload,

ESP); (Internet Key Exchange, IKE). IP

. , , . ESP , , , . , IKE -.

(Point-to-Point Tunneling Protocol, ) Microsoft, VPN. , MS-CHAP, CHAP, SPAP . , ,

129

VPN, .

: -, - ; -, VPN-

; -,

.

Windows- Intranet. L2TP

, Cisco, Microsoft 3Com, . , L2TP (Layer Two Tunneling Protocol, ) Cisco Layer Two Forwarding (L2F). L2TP - IP- . CHAP, , , L2TP .

L2TP ( 2), -IP . L2TP , ATM, Frame Relay 802.11. , . 2.6

(Intrusion Detection System, IDS) . : .

(Network Intrusion Detection Systems, NIDS) ( ). . (Network Node IDS).

(Host Intrusion Detection Systems, HIDS). , ..

NIDS : . IDS , . , , , . - , , , . , , , . IDS , ,

130

. IDS .

IDS 2.40.

. 2.40 IDS

, , . IDS , . - . , , , IDS, . , ?

IDS . . , . , , . , , , , . , . , , , . IDS . , , , IDS (. 2.41).

131

. 2.41

, , , , , . 802.1x/LEAP . , , , , . - DoS- , , . , IDS , TCP SYN, DoS-, , , ( 1).

1) : ; ,

; ; ,

; ,

/. ,

, , , 1 2.

2) , : ; ; ; , ; ;

132

, ;

; ; , SSID SSID ; SSID; SSID; SSID ,

; -, ; -; -. ,

, , , -, , SSID 2, .

3) , 802.1x/: ,

802.1x; ,

; ; ; ; ; . ; , (

); 802.1x/.

, 802.1x, DoS-, . , 1.

4) , WEP: ; , WEP-; , WEP- ; IV; IV; IV; WEP , TKIP; WEP-. ,

.

133

5) , : ; ; ; ; ; .

. , IDS, , .

6) : , ; ,

IDS; , ; ; , MIC,

; . ,

, , , DoS- 802.11i . , , , .

IDS . AirDefense Guard Isomair

Wireless Sentry. .

134

3. 3.1

,

. , . , , , .

, , . , .

, .

3.1.1

. . , . .

. , . , (. 3.1). , . . 3.1 ( ).

() () . 3.1

135

. , . , . . 3.1 ( ). ; . 3.1.2

. , ( ) (. 3.2).

() ()

. 3.2 () ()

, . . , , , .

E H . - , . , , .

, , , . .

3.1.3

. , , ,

136

.

(dB), (dBi) ,

. , (. (3.1) (3.2)).

=

==

2

110

2

110 log2log V

VPP

(3.1)

=

==

2

110

2

110 log20log10 V

VPP

(3.2)

1P (), 2P (),

1V (), 2V ().

3.1:

100 , 50 , :

L 350100lg10 ==

, .

10 5 3 . 3.2:

, . , , , 4 , 12 , - 35 , - 10 . (-12+35-10)=13 . :

4lg1013

PG ==

P 8,791043,1 ==

, . , . 1 , dBW (-). :

1

,lg10, = (dBm) (-

). 1 .

137

1

,lg10, =

. , . , , ( ), . 3.2

, , , . 3.2.1

(. . 3.3) . , . 2 . , , . .

. 3.3 ( 2 )

, . 3.2.2

30 , . (. 3.4).

138

. 3.4 ( 30 )

30 . , . . , . . , , . , . , 802.11a, 802.11b 802.11g , , . 3.3

, . . , . , . , . :

; ; ; ;

3.3.1

. , , . , ( ) . .

1) , .

2) ,

139

, . 3) ,

.

. . , , . , , . , , .

. , , , . . , , . 3.3.2

. , , , . . , , . . tP rP . , 10.

( ) ( )2

224

trr

t

GGd

PP = (3.3)

tP ;

rP , ; ; d , ;

tG ;

rG . ,

, .

3.3.3

, , , , ,

140

. . , .

: ; ; ; .

. , .

, . , , , . , , 1f

2f , 21 ff + . , 21 ff + .

, . . , . . , , . , ( ) . . , , .

, . , (, ) () . 3.3.4

, . ( , ) , , . . , , , , . 3.4 /

141

/. / 1

1 ( )0NEb . , , R /. , 1 = 1 /, : bb STE = ( S ; bT ). R bTR 1= . , , 1 ,

kTN =0 (/), (3.4)

0N 1 ; k , k 23103803,1 = ; T ( ),

, ,

kTRS

NRS

NEb ==

00

. (3.5)

0NEb , () . 0NEb , , . , 0NEb R .

. , , . , .

3.3:

, , 0NEb 8,4 10-4 ( 1 10000). 290 , 1 /, , ?

: (3.5) S :

kTRNE

S b0

= :

)(log10log10 1000

10 kTRNEkTR

NES

bb +

=

=

1 = 1048576 , 37,135)10485762901038,1(log104,8 2310 =+= S

SS

1410 10904,210 ==

142

, -135,37 .

3.5 3.5.1

. :

)lg(lg2033 DFFSL ++=

FSL (free space loss) (); F (); D ().

FSL .

: rtrtt LLPGGPY ,,min,,,, ++= (3.6)

tP , ;

tG , ;

rG , ;

Pmin, ;

tL , ;

rL , . .

(, 1-2 ) : 90 94 . , . 3.1 802.11a,b,g.

3.1

54 / -66 48 / -71 36 / -76 24 / -80 18 / -83 12 / -85 9 / -86 6 / -87 .

-

. , .

FSL : SOM-YFSL = (3.7)

143

SOM (System Operating Margin) (). , :

;

: , , ; , , - . SOM 10 . , 10-

. F 3.2.

3.2

() 1 2412 2 2417 3 2422 4 2427 5 2432 6 2437 7 2442 8 2447 9 2452 10 2457 11 2462 12 2467 13 2472 14 2484

:

= FFSL

Dlg

2033

2010 . (3.8)

3.4: , 56

/ 6 / DWL-2100AP DWL-G132. :

DWL-2100AP DWL-G132: 16 ; DWL-2100AP 54 /: -66 ; DWL-2100AP 6 /: -88 ; DWL-G132 54 /: -66 ; DWL-G132 6 /: -87 ; DWL-2100AP: 2 . DWL-G132: 0 .

- , .. .

: 1) 54 /. FSL

4710-)66(216 =+=FSL (3.8) ( ):

144

D 50046,0102437lg

2033

2074

54 ==

2) 6 /. FSL

9610-)88(216 =+=FSL (3.8) :

D 580579,0102437lg

2033

2096

6 ==

3.5.2

, (. 3.5). (, , ) (, ) , , .

. 3.5 ,

:

DSSD

fR +=

13,17 (3.9)

R ();

DS , ();

f (). :

20% . 40% , .

, . . , .

145

, .

3.5: 10 (. . 3.5),

7 .

: S, D 3.2 (3.9), :

R 06,167373

437,213,17 =+

= . , , 16 .

3.6 -

, , . , , , , .

, , , , . , ( ) , , , , , .

, , (indoor) . (outdoor) . 3.6.1 -

. 3.6 - , . , . , , , .

146

. 3.6 -

1. D-Link

25 (, DWL-2100AP, DWL-3200AP, DWL-8200AP, DWL-2700AP, DWL-7700AP, DWL-G520 ..) , . , .

, - . :

, () - ().

, .

2. , , ,

, . , , , . . , , , . , , , , , , 1,5 .

, , NCS F24XXX, . , , .

3. SMA-RP-plugN-type-male pigtale

indoor , SMA-RP ( SMA),

147

- N-type (. 3.7).

. 3.7 pigtale

Pigtale- (outdoor) D-Link, . 0,5 .

4.

( 0,5 ) , 220. 2 N-type-female. .

5. TLK-N-type-MM N-Type Male-Male (. 3.8)

female male, , ( N-type-maleN-type-female).

. 3.8 TLK-N-type-MM

, , , , , , , , (female), , (male). ,

148

. N-type-maleN-type-male.

6. (, HQNf-Nm15) 15 N-type (female)N-type (male) (. 3.9).

. 3.9 N-type (female)N-type (male)

, , 15- ( ), :

,

, .

7. 2,4 (, NCS24XX) (. 3.10)

, .

149

. 3.10 2,4

. . . :

, - , - , , . , , , .

3.6:

200 NCS2405, 10-100 , 500 . 100 , .. 3 , 0,3 / 2,4 .

,

, ; , , , .

3.7:

indoor ( 16 ) NCS2401 . 3.6. 2,4 0,3 /.

: (

): Y = 0,5 (pigtale)+0,5 ()+6 (15-

( 0,3 /)+3 0,75 ) = 7,75 , , , ,

150

16-7,75 = 8,25 . NCS2401

4 (6 ). , :

8,25-6=2,25 ; 2,25/0,3=7,5 ,

.. 7,5 . , 22,5 .

, . , -98 ; 30 . 10 (7,75 +2,25 ). : -98+30-10=(-78 ). 3.1 , :

(-78 ) < (-76 ) , 24 /. , , , .

3.3 .

3.3

. . 2 6 6 7 12,4 0,5 - 1 3- 20 / 0,02 0,05 / 0,35 pigtale 0,5 NCS F24XXX 1,5 / 0,3 N-type 0,75 0,5

8. (, HQNf-Nm1,5)

HQNf-Nm1,5 () N-type(female)N-type(male) 1,5 .

9. D-Link . N-

type(female)N-type(male).

10. (, ANT24-2100) 21 . : N-type-female.

3.6.2 -

. 3.11 , , - .

151

. 3.11 -

3.11 : 1. DWL-2100AP; 2. pigtale ( ); 3. ; 4. ( ); 5. ANT24-1400. , ,

, . , .

, . 6 , , . 3.6.3 ,

, . 3.12, , .

. 3.12 ,

3.12 : 1. DWL-2100AP; 2. pigtale ( );

152

3. ( ); 4. ANT24-1400. ,

, , . indoor .

.

153

. D-LINK

D-Link :

AirPlusG - 802.11g 2,4 ;

AirPlusXtremeG - 802.11g 2,4 ;

AirPlusXtremeG MIMO - 802.11g 2,4 ;

AirPremierAG - 802.11a/b/g 2,4/5 ;

AirPremier - 802.11b/g 2,4 ;

802.11g

AirPlusG -

. , , - PCI/CardBus/USB-. 802.11g 54 / 802.11b. WPA/WPA2. Web-. DWL-G700AP AirPlusG 802.11g, 54 /

. .1 DWL-G700AP

802.11b/g 1 10/100Base-TX : , WEP, WPA WPA2 802.1

154

MAC- SSID DHCP / Web-

DI-524/524UP AirPlusG 802.11g, 54 /

. .2 DI-524UP

802.11b/g 4 10/100Base-TX LAN 1 USB 1.1 (DI-524UP) WEP, WPA WPA2 802.1 NAT, VPN pass-through, MAC/IP/URL DHCP / Web-

802.11g

- D-Link AirPlusXtremeG, AirPremierAG AirPremier 108 /. , PCI, PCMCIA, USB. , AirPremier AirPremierAG 802.3af Power over Ethernet (PoE). SNMP v.3, . 108 / - (Turbo mode). - Dynamic Turbo Static Turbo.

Dynamic Turbo . ,

155

, - 802.11g. , 54 /.

Static Turbo , - . , .. .

Super G without Turbo mode ( 54 /):

Packet Bursting ( ): DIFS (Distributed InterFrame Space).

Fast Frames ( ): .

Hardware Compression and Encryption ( ): Lempel-Ziv .

Super G with Turbo mode Packet Bursting, Fast Frames, Hardware Compression and Encryption Multi-Channel Bonding.

Multi-Channel Bonding ( ): () .

DWL-2100AP AirPlusXtremeG 802.11g, 108 /

. .3 DWL-2100AP

802.11b/g 1 10/100Base-TX

156

: , WDS , WDS (), ,

WEP, WPA WPA2 802.1 MAC- WLAN STA 8 SSID SSID 802.1Q VLAN Tagging WMM (Wi-Fi Multimedia) DHCP / Web- , SNMP v.1, v.3, Telnet

DI-624/624S AirPlusXtremeG 802.11g, 108 /

. .4 DI-624S

802.11b/g 4 10/100Base-TX LAN 2 USB 2.0 (DI-624S) WEP, WPA WPA2 IP- NAT, SPI, DMZ, VPN pass-through, MAC/IP/URL QoS (DI-624S) 6 (DI-624S) Web-

DGL-4300 GamerLounge 802.11g, 108 /

157

. .5 DGL-4300

802.11b/g 4 10/100/1000Base-T LAN 1 10/100Base-TX WAN 5 dBi WDS GameFuel Priority WEP, WPA WPA2 NAT, VPN pass-through 256 ( ) / 1000

Web-

DWL-2200AP AirPremier 802.11g PoE, 108 /

158

. .6 DWL-2200AP

802.11b/g 1 10/100Base-TX 5 dBi 802.3af PoE : , WDS , WDS () WEP, WPA WPA2 AES MAC- SSID 802.11i-ready DHCP / Web- , SNMP v.3, Telnet

DWL-3200AP AirPremier 802.11g PoE, 108 /

159

. .7 DWL-3200AP

802.11b/g 1 10/100Base-TX 2 5 dBi 802.3af PoE : , -, - WEP, WPA WPA2 802.1 MAC- 8 SSID SSID 802.11i-ready DHCP / Web- , SNMP v.3, Telnet

DWL-7100AP AirPremier AG 802.11a/b/g, 108 /

160

. .8 DWL-7100AP

802.11/b/g 1 10/100Base-TX : , WDS , WDS (), ,

WEP, WPA WPA2 802.1 MAC- WLAN STA SSID DHCP / Web- , SNMP v.3, Telnet

DI-784 AirPremier AG 802.11a/b/g, 108 /

. .9 DI-784

80

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