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Sending Attachments or Sharing Files Via The Web

It is not a good idea to send large attachments through email as they greatly increase the load on any email system and may be blocked, altered, or renamed. See:

Blocking and Renaming of Some Email Attachments

The UW has an absolute limit of 60 Mbytes for an attachment, but some email programs, such as WebPine, are limited to only 20 Mbytes, and other sites may have different limits. And large attachments may never make it through flaky networks.

You can avoid all of these problems if you send attachments via the Web. You do this by storing your "attachment" in your own Web space and just sending the URL.

Below are some scenarios that let you create a directory of files that you own but which are accessible to other people through the World Wide Web. Only the files in that specific directory can be viewed or copied by other people, but in no case can they delete, augment, or modify them in any way. Also, other people may not view or copy any files in any of your other directories -- just the ones in the directory you designate.

The files in this directory can be almost any type: plain text, HTML text, graphic (such as .gif or .jpg), MS Word files, PowerPoint presentations, compiled binary files, etc.

Note: in some cases an application will immediately grab a file when a user tries to save it because the application (e.g., QuickTime) has been set to activate files with that extension by default. In that case the person who tries to save the file needs to first disable the default action in their PC for that type of extension.

Also, the scenarios listed below do not lock you into a fixed mode: it is generally not difficult to change your mind. For example, if you assume you are not going to use your UW Web-site to host your web pages, and then decide later that you wish to do so, you can easily make that happen and still use the Web to share your files.

Here is the scenario that we suspect you are most likely to encounter:

You have a UW NetID: we will use "joeschmoe" as an example
You have a Web space in "public_html" on Homer
You have a sub-directory under "public_html" as a place to store your files -- we will use "MyFiles" as an example
You have a newer UWICK kit on your PC which displays an icon for "SSH Secure File Transfer"
You have a large PowerPoint file named "big.ppt" on your desktop

Then you send your "big.ppt" attachment as follows:

Invoke "SSH Secure File Transfer" by double clicking on its icon
Select "homer.u.washington.edu" as the "Host"
Supply your UW NetID and password. It should open up a window with two panes: the one on the right is for Homer.
Double click on the "public_html" folder in the right pane to open it
Drag "big.ppt" to your "MyFiles" sub-directory
Quit SSH Secure File Transfer

Then to send the attachment, all you do is send email telling the person to click on this URL:

http://staff.washington.edu/joeschmoe/MyFiles/big.ppt

In addition, other scenarios are possible. You may explore them at: Setting Unix Permissions For Web Pages

Here are some other scenarios that may better apply to you:

You have no UW web site and wish to make a subset of your files available to others: Scenario 1
You have no UW web site and wish to make a subset of your files available to others under some restrictions: Scenario 2
You have no UW web site and wish to make a subset of your files available to others under ID/password protection: Scenario 3

You do have a UW web site and wish to make a subset of your files available to others: Scenario 4
You do have a UW web site and wish to make a subset of your files available to others under some restrictions: Scenario 5
You do have a UW web site and wish to make a subset of your files available to others under ID/password protection: Scenario 6