Sends twice the size of the email

Asked by Don Task on 2012-01-17

When I send an email with an attachment, the total size of the attachment is displayed by evolution, however, when I watch the network traffic for the send and receive bytes, the send size is virtually twice the volume of the email size. For example, a text email with an 11mb attachment, will be sent at about 22 mb.

Is there a background email address that evolution is sending to that is hidden to me?
How can I view the traffic and destinations related to the email being sent?

ProblemType: Bug
DistroRelease: Ubuntu 11.10
Package: evolution 3.2.1-0ubuntu1
ProcVersionSignature: Ubuntu 3.0.0-14.23-generic 3.0.9
Uname: Linux 3.0.0-14-generic i686
ApportVersion: 1.23-0ubuntu4
Architecture: i386
Date: Mon Jan 16 23:32:58 2012
ExecutablePath: /usr/bin/evolution
InstallationMedia: Ubuntu 10.10 "Maverick Meerkat" - Release i386 (20101007)
SourcePackage: evolution
UpgradeStatus: Upgraded to oneiric on 2011-12-22 (26 days ago)

Question information

Language:
English Edit question
Status:
Solved
For:
Ubuntu evolution Edit question
Assignee:
No assignee Edit question
Solved by:
Marc Deslauriers
Solved:
2012-01-21
Last query:
2012-01-21
Last reply:
2012-01-17
Don Task (syntactics) said : #1

This incident may be specific to the user and not an evolution problem in and of itself. Perhaps other users should watch the outgoing traffic when sending an email with a known attachment size, such as 1 mb and determine if they also observe the same effect.

Best Marc Deslauriers (mdeslaur) said : #2

Sounds about right once the attachment is mime-encoded. Encoding the attachment so it can get included in email, which was originally designed for text, can make it's size grow to practically double it's size.

See: http://en.wikipedia.org/wiki/MIME

Don Task (syntactics) said : #3

Thanks for the reply. I followed the wikipedia link and learned quite a bit, however, I was not able to determine that this is the actual cause, but I accept that it most likely is. Since the attachment I send was a PDF, the explanation sounds correct that it would be necessary to MIME the pdf to allow it to be handled as a text email.

Thank you again.
Don Task