Anatomy of an email message

Question

Hi,

What are the various parts to an email message?

I'm working with these 3rd party components, and so far from what I understand are:

1. emails have unique messageID's (per server I would presume)

2. emails have headers

3. emails have body text that can be either html or plain text.

4. attachments have to be parsed using mime, and each mime part can have different types like: multipart/ applicatoin/octet-stream and filenames.

side question, where exactly is the documentation that these 3rd party components have to adhere to?

Answer 1

I think its time to read some RFCs. ;)

RFC2822 - Internet Message Format
http://www.faqs.org/rfcs/rfc2822.html

RFC2045 - Multipurpose Internet Mail Extensions (MIME) Part One
http://www.faqs.org/rfcs/rfc2045.html

RFC2046 - Multipurpose Internet Mail Extensions (MIME) Part Two
http://www.faqs.org/rfcs/rfc2046.html

RFC 2049 - Multipurpose Internet Mail Extensions (MIME) Part Five: Conformance Criteria and Examples
http://www.faqs.org/rfcs/rfc2049.html

RFC2821 - Simple Mail Transfer Protocol
http://www.faqs.org/rfcs/rfc2821.html

Answer 2

If sent by an MS Exchange server which is not configured properly, an email can be a single blob in a propriety binary format known as TNEF that is attached to a message which contain little else as a file usually named winmail.dat.