1 .
1.1 .
(HTTP) - , , . HTTP World Wide Web (WWW) 1990 . HTTP, HTTP/0.9, . HTTP/1.0, RFC 1945 [6], , MIME- , /. , HTTP/1.0 - (hierarchical proxies), , , (virtual hosts). , , , "HTTP/1.0", , , .
"HTTP/1.1". , HTTP/1.0, .
, , , , (annotation). HTTP , . , (URI) [3] [20], (URL) [4] (URN), , . , , (MIME).
HTTP -/ (proxies/gateways) , , SMTP [16], NNTP [13], FTP [18], Gopher [2], WAIS [10]. , HTTP (hypermedia) .
1.2 .
, RFC 1123 [8]. :
- , (MUST)
- , .
- , (SHOULD)
- , , .
- , (MAY)
- , , - .
, . , , , .
1.3 .
, , HTTP .
- (connection)
- , .
- (message)
- HTTP , , , 4 .
- (request)
- HTTP , , 5.
- (response)
- HTTP , , 5.
- (resource)
- , URI, 3.2. ( , , , ) .
- (entity)
- , . , 7.
- (representation)
- , (Content Negotiation), 12. , .
- (content negotiation)
- , 12. ( ).
- (variant)
- , , . "". "" , .
- (client)
- , .
- (user agent)
- , . , , (spiders), .
- (server)
- , , . , ; , , , . , , -, , (tunnel), , .
- (origin server)
- , .
- - (proxy)
- -, , . -, , . - , .
- (gateway)
- , . -, ; , .
- (tunnel)
- -, . , HTTP , , , HTTP. , .
- (cache)
- , , , , . , , () . , , .
- (cachable)
- , . HTTP 13. , .
- (first-hand)
- , , -. , .
- (explicit expiration time)
- , , .
- (heuristic expiration time)
- , , .
- (age)
- - , , .
- (freshness lifetime)
- .
- (fresh)
- , .
- (stale)
- , .
- (semantically transparent)
- , " " , , , . , ( (hop-by-hop) ), , , .
- (validator)
- (, (Last-Modified time)), , , .
1.4 .
HTTP - /. , , URI, , MIME- , , , , , , . , , , MIME- , , , , , . HTTP MIME 19.4.
HTTP , . , (v) (UA) (O).
--------------------->
UA -------------------v------------------- O
<-----------------------
, / . : -, , . - -, URI , , , URI. - , () , , . ; , ( Firewall), .
----------------------------------->
UA -----v----- A -----v----- B -----v----- C -----v----- O
<------------------------------------
(A, B, C) . . , HTTP , , . , . , B , A, / , C, , .
, , . , / , , . , , B O ( C) , UA, A.
------->
UA -----v----- A -----v----- B - - - - - - C - - - - - - O
<--------
, , , . HTTP 13.
, -, World Wide Web; -, , , , , CD-ROM, . HTTP - , PDA . HTTP/1.1 , , web , , .
HTTP TCP/IP . TCP - 80, . HTTP , . HTTP , , ; HTTP/1.1 - , .
HTTP/1.0 /. HTTP/1.1, /, ( 8.1).