From 5b22a9515baf444179d09496feb4d5e185c6c9a9 Mon Sep 17 00:00:00 2001 From: Runxi Yu Date: Sun, 28 Apr 2024 15:34:38 +0800 Subject: Add the old ima delivery.txt docs --- old/delivery.txt | 38 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 38 insertions(+) create mode 100644 old/delivery.txt diff --git a/old/delivery.txt b/old/delivery.txt new file mode 100644 index 0000000..e991f81 --- /dev/null +++ b/old/delivery.txt @@ -0,0 +1,38 @@ + Internet Mail Delivery Protocol + +The objective of Internet Mail Delivery Protocol (IMDP) is to deliver +mail between mail servers reliably, securely and efficiently. This +document is an informal specification of IMDP. + +IMDP is the mail delivery protocol of the Internet Mail Architecture, +which addresses the communication of mail between mail servers. It is +not complete by itself. Seperate protocols are being developed to +address mail submission, and mail retrieval between user agents and mail +servers. The format of mail data transferred with IMDP is also +documented seperately. + +The Internet long had existing mail delivery protocols, such as the +Simple Mail Transfer Protocol. However, due to the lack of security +considerations, countless amendments have been added to the protocol +such as SMTP over TLS, DMARC, DKIM, and SPF. In particular, TLS is used +for secure transport, while DMARC, DKIM, and SPF are used for domain +name authentication. However, this combination is complicated and is +cumbersome to maintain, especially with its heavy dependence on DNS. +This protocol attempts to address these coherently. + +The Internet Mail Delivery Protocol works over TLS TCP. At the request +of a user, the sending IMDP server server establishes a TLS bytestream +to the receiving IMDP server, based on the hostpart of the recipients of +the mail. The TLS connection MUST use a TLS client certificate, +recognized in the X.509 public key infrastructure (e.g. signed by a +certificate authority), that corresponds to the domain of the return +path, as in the return path's hostpart is in the TLS client +certificate's commonName or subjectAltName. The sending-IMDP then sends +a IMDP mail data's headers, in the IMDP mail format. The receiving-IMDP +verifies the validity of the mail headers, for example, whether the +sending-IMDP is authorized to send mail for the domain indicated in the +headers. If the receiving-IMDP can receive the mail as specified by the +headers, the sending-IMDP sends the mail data. If not, the +receiving-IMDP rejects the mail with a reply specifying the reason. + +vim: textwidth=72 colorcolumn=72 -- cgit v1.2.3