comast email issues, who else has them?

william(at) william at
Mon Sep 11 17:29:14 UTC 2006

On Mon, 11 Sep 2006, Tony Finch wrote:

> On Sat, 2 Sep 2006, Fergie wrote:
>> Ack: X-Originating-From should be mandatory.
> Far better to use a Received: header stating HTTP in the "with" protocol
> field. (And the IANA registry should be updated to include that as one of
> the standard values.)

That suggestion is likely to be contrary to SMTP design. Received trace 
fields are for use of recording of where data that was RFC2822 formatted 
came from and how. Use of these fields also assumes that start of email 
transmission took place somewhere else. The "with" clause in Received is 
used to indicate the "transport" protocol but assumes that data itself
is already properly formatted (compare to that the same type of L7 protocol
can use either TCP or UDP; this is not perfect fit but gives you some idea).

In case of web-based email services however, the start of the transmission 
is the webserver which is the one putting data in RFC2822 format and 
initiating the transmission. So use of "with HTTP" is inappropriate here -
the only case where "with HTTP" would be appropriate is when email client
like Thunderbird creates entire email message as it normally would but 
instead of using SMTP or SUBMIT to send it, it is sending the data using 
HTTP PUT or SOAP or XML-RPC - this is not the case with web-based email.

If you really want to indicate the source of transmission for non-SMTP
origination point, the best is to create new trace field for this purpose.
With Received the closest clause would be "via" but I think via is 
largely for use with complete message being gatewayed through non-SMTP 
protocol and this is probably not the correct use of it either.

William Leibzon
Elan Networks
william at

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