Panasonic DP-180, Service Manual

Page: 314 / 375

314
UF-9000
APR 2006
Ver. 3.0
DP-180/190
9.6. SMTP (Simple Mail Transfer Protocol)
The objective of Simple Mail Transfer Protocol (SMTP) is to transfer mail reliably and efficiently.
SMTP is independent of the particular transmission subsystem and requires only a reliable ordered data
stream channel.
The SMTP design is based on the following model of communication: as the result of a user mail request,
the sender-SMTP establishes a two-way transmission channel to a receiver-SMTP. The receiver-SMTP
may be either the ultimate destination or an intermediate. SMTP commands are generated by the sender-
SMTP and sent to the receiver-SMTP. SMTP replies are sent from the receiver-SMTP to the sender-SMTP
in response to the commands. Once the transmission channel is established, the SMTP-sender sends a
MAIL command indicating the sender of the mail. If the SMTP-receiver can accept mail it responds with an
OK reply.
The SMTP-sender then sends a RCPT command identifying a recipient of the mail. If the SMTP-receiver
can accept mail for that recipient it responds with an OK reply, if not, it responds with a reply rejecting that
recipient (but not the whole mail transaction). The SMTP-sender and SMTP-receiver may negotiate several
recipients. When the recipients have been negotiated the SMTP-sender sends the mail data, terminating
with a special sequence. If the SMTP-receiver successfully processes the mail data it responds with an OK
reply. The dialog is purposely lock-step, one-at-a-time. For more detail, please refer to the URL http://
www.imc.org/rfc821
9.6.1. Mail Header Sample
SMTP Server
PC PC DNS Server POP Server
Internet
SMTP
POP 3
Internet Mail Sending and Receiving
Received: from nwr35
by labo.pcc.com (8.9.3/3.7W-RDMG) with SMTP id PAA09157
for <freeport@labo.pcc.com>; Sun, dd Mmm yyyy 15:04:48 +0900 (JST)
Date: Sun, dd Mmm yyyy 15:04:48 +0900 (JST)
Message-Id: <199908200604.PAA09157@mlsv2.labo.pcc.com>
Mime-Version: 1.0
X-Mailer: Internet FAX, Panasonic
From: "Panasonic" <ifax98-us@labo.pcc.com>
Subject: IMAGE from Internet FAX
To: freeport@labo.pcc.com
Content-Type: multipart/mixed; boundary="+-+-+-Pan-+-+"
X-UIDL: 8f32e4b1d691fdfc28daa812d913f572
Delivery route
Message ID
Content-Type