User Datagram Protocol (UDP)
o best effort
21.
DNS ( ) IP ( IP- )
:
a.
b.
c.
d.
e.
, - //
- ( )
- 127 63 , 255
DNS- DNS-. DNS- / .
DNS- , DNS-
DNS- (query) ( )
o
o
o ( )
o ( )
22.
, , , .
SMTP (Simple mail transfer protocol)
Pop (Post office protocol)
IMAP (Internet message access protocol)
SMTP (Simple Mail Transfer Protocol)(25TCP) , TCP/IP
SMTP
HELO
MAIL FROM
RCPT TO
DATA
QUIT
SMTP 25. HELLO IP :
C: HELLO 195.161.101.33
S: 250 smtp.mail.ru is ready
(, ):
C: MAIL FROM:<drozd> '
S: 250 OK
C: RCPT TO:<[email protected]> '
S: 250 OK
, ( )
C: DATA
S: 354 Start mail input; end with <CRLF>.<CRLF>
CRLF.CRLF
S: 250 OK
C: From: Drozd <[email protected]>
C: To: Drol <[email protected]>
C: Subject: Hello
CRLF, .
C: Hello Drol!
C: You will be die on next week!
CRLF.CRLF
S: 250 OK
, QUIT:
S: QUIT
C: 221 smtp.mail.ru is closing transmission channel
POP3 (110TCP) ,
|
|
|
POP3
n USER [] .
[] , .
n PASS [] .
[] .
n APOP [] [digest] (digest).
[] , .
[digest] - , , MD5. .
n STAT ,
n LIST [ ] , . , , . , , .
[] ( ).
n RETR [ ] .
[] .
n DELE [ ] . , , ( QUIT, , , , ).
[] .
N QUIT
IMAP4 (143 TCP) ,
n 2 : online offline
n 1
n
23. http
HTTP (HyperText Transfer Protocol ) ( ).
n
n
n
n
n
n
n
n
n Hypertext markup language ( ) WWW.
n HTML , .
URI (Uniform Resource Identifier ) , : , , , , .. ( )
n URI:
<>:<>
n :
n http://www.stankin.ru
n mailto:[email protected]
file://C:\Windows\system32\drivers\etc\hosts
URL (Uniform Resource Locator ) .
n URL:
<>://<>:<>@<>:<>/<URL->
n :
n ftp://User1@Pass:www.stankin.ru:8080/index.php?at=12
n http://www.stankin.ru/news/index.html
24.
(, circuit switching) ( ) (/ , , , , . ., ).
|
|
|
; '
;
;
, , , ;
, ;
, , , ( ) , ;
, ,
.
25.
(. packet switching) , , . , , .
( ) (packet). , , , - . . , . (datagram), .
1.
2.
1.
2.
, , . ( ) , . , , , , .
26.
Wi-Fi
Ad Hoc
Infrastructure
Ad Hoc Wi-Fi ( )
:
()
/
:
:
256
:
( .. )
2048
(Wireless access point) ,
|
|
|
(SSID)
, broadcast
MAC-
MAC
(WEP, WPA, WPA2)
WEP
WPA
n 802.1x Extensible Authentication Protocol (EAP) -
n Temporal Key Integrity Protocol (TKIP)
n
n
n Message Integrity Check (MIC)
WPA
n 48
n 128
n (Per Packet Keying, PPK)
n MIC, Message Integrity Check
n , forgery attack (bit-flip attack)
WPA2
n 256
n AES
n WPA
n Per Packet Keying
n Message Integrity Check
n 802.1x (EAP RADIUS)
| WEP | RC4 , | |
| WPA | TKIP , 802.1x (EAP Radius) | |
| WPA2 | AES, 802.1x | , |
Wi-Fi:
()
(AP/AP)
WEP
IrDA (Infrared Data Association) ,
:
() ()
IrLAP :
IrLMP LM-MUX :
/
IrLMP LM-IAS :
Bluetooth .
Bluetooth . , 10 100, . 255 , 8 . , . , . , , , .
|
|
|
, . , , , .
, Bluetooth, Bluetooth . Bluetooth , , : , , .
Bluetooth (Pairing), . ; , , . Bluetooth , PIN- Bluetooth. , , PIN-. , , , , PIN- .
n Bluetooth PIN ( )
n PIN
n E0
n :
n
n
n
n
n Bluejacking
