SMTP
HELO {SP} {string}{CRLF} | SMTP- , {SP} | |
QUIT{CRLF} | SMTP-. | |
MAIL {SP} FROM:{reverse-path} {CRLF} | . | |
RCPT {SP} TO:{forward-path} {CRLF} | . | |
DATA {CRLF} | . {CRLF}. | |
VRFY {SP} {string}{CRLF} | . | |
EXPN {SP} {string}{CRLF} | . | |
NOOP{CRLF} | ||
TURN{CRLF} | 200 OK | |
RSET{CRLF} | ||
HELP{CRLF} | ||
SMTP- : - , S: -
S: ( )
C: ( 25 )
S:220 mail.company.tld ESMTP CommuniGate Pro 5.1.4i is glad to see you!
C:HELO
S:250 domain name should be qualified
C:MAIL FROM:
S:250 [email protected] sender accepted
C:RCPT TO:
S:250 [email protected] ok
C:RCPT TO:
S:550 [email protected] unknown user account
C:DATA
S:354 Enter mail, end with "." on a line by itself
C:Hi!
C:.
S:250 769947 message accepted for delivery
C:QUIT
S:221 mail.company.tld CommuniGate Pro SMTP closing connection
S: ( )
[email protected], [email protected], .
17) Pop3 (. Post Office Protocol Version 3 , 3) - , TCP/IP-. POP3 . , POP , , , , .
STAT
STAT . , , . , " +OK 4 223718" , 4 223718 .
LIST
LIST : , .
:
C | LIST |
S | +OK 4 visible messages (223718 octets) |
S | 1 333 |
S | 2 111293 |
S | 3 111285 |
S | 4 807 |
S | . |
4 , , , 333, 111293, 111285 807 .
|
|
, , , , .
LIST , :
C | LIST 2 |
S | + OK 2 111293 |
RETR
.
.
DELE
. . . , , .
NOOP
. .
RSET
.
QUIT
. - , QUIT .
18) IMAP (. Internet Message Access Protocol) .
TCP 143.
IMAP , . , , , . () .
IMAP POP3.
POP3 , . , , , , .
, POP3, , , . .
POP3 , . IMAP , , . , .
POP , . IMAP , , .
|
|
, IMAP4, (, , . .); .
IMAP4 , . , IMAP4 Access Control List (ACL) Extension (RFC 4314) .
.
IMAP4 .
IMAP
LOGIN
IMAP . , .
AUTHENTICATE
IMAP . IMAP. . AUTHENTICATE, base64. , base64. , , NO. . , LOGIN.
CLOSE
. , , \DELETED, . .
LOGOUT
. - \deleted, .
CREATE
. .
DELETE
. IMAP , . .
RENAME
. , , .
SUBSCRIBE
. , . , , , , .
UNSUBSCRIBE
. , . .
LIST
; .
LSUB
LIST , SUBSCRIBE. , LIST.
STATUS
. , . , . STATUS SELECT EXAMINE.
:
MESSAGES
RECENT \recent
|
|
UIDNEXT UID,
UIDVALIDITY
UNSEEN \seen
APPEND
. , ( ), ( ) .
:
\Seen
\Answered
\Flagged
\Deleted
\Draft
\Recent ,
, . \Recent.
, , .
, .
:
C A003 APPEND saved-messages (\Seen) {247}S + Ready for literal dataC Date: Mon, 7 Feb 1994 21:52:25 -0800 (PST)C From: Fred Foobar <[email protected]>C Subject: afternoon meetingC To: [email protected] Message-Id: <[email protected]>C C Hello Joe, do you think we can meet at 3:30 tomorrow?S A003 OK APPEND completedMULTIAPPEND, RFC 3502, .
CHECK
. , , , , . CHECK. .
EXPUNGE
, \DELETED, . EXPUNGE .
SEARCH
.
, , , . .
FETCH
. . POP3, IMAP .
STORE
.
COPY
.
UID
FETCH, COPY, STORE SEARCH. UID .
CAPABILITY
IMAP .
NOOP
. , . NOOP . , NOOP .
19) Network Time Protocol (NTP) . NTP . NTP . (David L. Mills) 1985 . NTP 4.
|
|
NTP (stratum). 1 , , GPS, ( ) . 2 1, .
NTP 64- (8 ), 32- 32- , 232 , 2−32 . NTP 232 (136 ), ( 50 ). , 1 1900 , 1970, NTP 70 ( ), Windows Unix-. NTP . NTP . Microsoft Windows, W32Time ( w32time.dll, svchost.exe), Linux - Ntpd.
SNTP . , , .
20) QoS (. Quality of Service ) , , , , .
:
- (Bandwidth), , . bit/s (bps), kbit/s (Kbps), Mbit/s (Mbps), Gbit/s (Gbps).
- (Delay), .
- () .
- (Packet loss). , .
, : .
, FIFO: (First In First Out). , : , FIFO ( ), , , . , ToS. : . QoS QoS. , VoIP FTP, SMTP .