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4.2 メッセージヘッダー HTTP header fields, which include General-Header (Section 4.3), Request-Header (Section 5.2), Response-Header (Section 6.2), and Entity-Header (Section 7.1) fields, follow the same generic format as that given in Section 3.1 of RFC 822 [7]. Each header field consists of a name followed immediately by a colon (":"), a single space (SP) character, and the field value. Field names are c