Module 2 Lists

"What are the pros and cons of email list vs discussion boards?"

Email lists

Pros

• If a user is interested in multiple groups/interests/hobbies, email list will deliver all of this information to one place. Making this an efficient way to keep up to date.
  
• Low bandwidth. If users are on a slow, expensive (rural, developing economies, mobile devices) or shared connection this will be important.
• Being text based with attachments frowned upon or banned, lists are good for access by mobile devices.

Cons

• Volume can be cumbersome.
• Spam
• No attachments
• Off topic frowned upon or banned.
• Less interactive than boards. This is not true for all lists as a lot of online communities have boards as well.

Discussion boards

Pros

• Provides a sense of home or identity via a central location.
• Contains many areas of discussion so users can go off topic.
• Attachments and HTML.

Cons

• High bandwidth.
• More casual users means a generally lower quality of posts and lots of post that don't add anything to the discussion.
• More anonymity for users can mean more flaming and offensive posting.
• Requires users with multiple interests to visit many places, frequently to keep up to date.
  

Module 2 Email Tasks - 4

"What sort of filters do you have set up and for what purposes?"

Incoming mail passes through a spam filter first for obvious reasons, although like everyone I occasionally have to trawl through the spam folder to find legitimate mail. This is better than being confronted every log in by hundreds of annoying and offensive messages.
What few messages make it through the spam filter are then sorted by priority and sender. I only average 10-20 messages per day so these two filters are sufficient to prioritise and sort my mail.

Module 2 Email Tasks - 3

"In what ways can you ensure that an attachment you send will be easily opened by the receiver?"

The foolproof way is to communicate your intentions with the recipient prior to sending the file to ascertain what software they have and supply them a file format that is compatible. If this is not possible, stick to open formats (as opposed to proprietary) or formats that have a free and readily available reader/viewer/player. A link to this software and brief instructions on how to use it would be polite.

Some examples of open file formats are:

Document

• PDF - Portable Document Format. Formerly proprietary, this format was made 'open' in 2008. It is a container for documents that have text, bitmap and vector graphics.
• ODF - Open Document Format. Open office format for documents. Made popular by Sun Microsystems Open Office suite.
• HTML - Hyper Text Markup Language.
  

Multimedia

• PNG - Portable Network Graphics. Lossless bitmap image format developed to replace GIF.
  
• SVG - Scalable Vector Graphics. XML based file format developed by the W3C.
  

Module 2 Email Tasks - 1

In the words of Gloria Gaynor, "I am back, from outer space!". I have baulked at this module because of the email tasks. Web based mail has been my choice after all the pain of maintaining .pst file backups from within Outlook and the hassle of migrating isp's (and therefore email addresses).

Yahoo has been my primary mail account for years. Today I have finally buckled down and set up an additional mail address on my isp's server, set up Outlook and my shiny new Iphone with this new mail account. Of course everything was easy, except the Telstra part.

Now over to the Blackboard to do the "Email Tutorial". Back soon.

Task 1 : What information about a user's email, the origin of the message and the path it took can you glean from an email message?

This task seemed simple on the surface but needed a bit of reading to complete.

http;//www.visualware.com/resources/tutorials/email.html

http://www.sendmail.org/dkim/technicalOverview.html

These are the two sources that quickly and clearly explained the syntax used in the headers, but I also read wiki entries and other pages that gave partial information. The email header convention is like html headers, they are slighlty different btween versions and systems.. Header content depends on application used to create the message (plus deliberate spoofing) and the mailserver systems passed through.

For this task I sent myself a message from Yahoo to my new Bigpond address. Then in Outlook, right click on the message in the Inbox. Select Options from the menu, Internet headers.



Return-Path:
Received: from nskntingx07p.mx.bigpond.com ([66.163.178.121])
by nskntmtas06p.mx.bigpond.com with ESMTP
id <20090406003140.hnm57.nskntmtas06p.mx.bigpond.com@nskntingx07p.mx.bigpond.com>
for ; Mon, 6 Apr 2009 00:31:40 +0000
Received: from web34206.mail.mud.yahoo.com ([66.163.178.121])
by nskntingx07p.mx.bigpond.com with SMTP
id <20090406003139.dbli17747.nskntingx07p.mx.bigpond.com@web34206.mail.mud.yahoo.com>
for ; Mon, 6 Apr 2009 00:31:39 +0000
Received: (qmail 12471 invoked by uid 60001); 6 Apr 2009 00:31:37 -0000
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=yahoo.com; s=s1024; t=1238977897; bh=WQQeqrN9VMa1DV024/4J/HQCl+gGBcPoUDZpkwg1pWU=; h=Message-ID:X-YMail-OSG:Received:X-Mailer:Date:From:Subject:To:MIME-Version:Content-Type; b=oG+o3CAFfXV46okSpfreGb4h5MBk66iEnxaUhq335YMRcginKddhSlqhbRW/zd64i7e3lG7LXnqKBpto/L02Giqr0PNkkwCKuojpjurvX4LaScaUj/sDGJBWiMzKF3f9K3lc59T0VgO2OXDN1PwQBqZAm0AeBKNyLIFMl6wliTs=
DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws;
s=s1024; d=yahoo.com;
h=Message-ID:X-YMail-OSG:Received:X-Mailer:Date:From:Subject:To:MIME-Version:Content-Type;
b=UsmafdJMrygFdl54dqTYkZvoY4it/VtZW2cXeSsoH9G+AKuI1NBQp3w6bDaINdmU8XscZUs0HX2CT+8L5Tm7tgOj8117JSUFqJ6eTiPmotHA2S9vtyKrIqGcRQr4wKOk598RH81KMNHd/ZsFF8W5/Zj+vvd9HM4Cx+3MBA/9J4E=;
Message-ID: <292351.8925.qm@web34206.mail.mud.yahoo.com>
X-YMail-OSG: InYFs7gVM1l78.2oqOmdVfJXaTNoqcZEI0ysXA4dWbNx7d9z6wlFfSur3GlUkLjfQdJK7ueh3fyLfpziELrSjiHNUXZPKSRB51YXeb_qYPx7OCWhNMSVYZpfBRpBdPg7NgLGilc7hzjnVXF3cwRZKZ56EydeC2uuMRRYoaXaovVXNQW7urEhDR2NXKfgWv4yGt5H9IWh81tq7pLHbxyQMc8fi.Wz.VM.RDK1r0BsYZDkmQVFT5C9uoonvKpg.hSuAcdQFoCDJfrh5Qfj.MlRw.DZQIXODQQO.WzY9k0.evYKPIsKiqXP78e51SMNQDJNIRINQBcp4lNMcNIyO75soZhhPNGreLVmKo7Rpa90h2Y-
Received: from [121.218.223.76] by web34206.mail.mud.yahoo.com via HTTP; Sun, 05 Apr 2009 17:31:37 PDT
X-Mailer: YahooMailWebService/0.7.289.1
Date: Sun, 5 Apr 2009 17:31:37 -0700 (PDT)
From: Jason Radich
Subject: test
To: jason_radich@bigpond.com
MIME-Version: 1.0
Content-Type: multipart/alternative; boundary="0-1432617849-1238977897=:8925"
X-RPD-ScanID: Class unknown; VirusThreatLevel unknown, RefID str=0001.0A150202.49D94D6C.0015,ss=1,fgs=0

From top to bottom this header text contains:

• Return-Path: reply address. Can be spoofed.

• Received: As messages move through mail servers, a new Received header line is added to the beginning of the headers list. Each of these lines contain tokens, being: (from), (by), (id), (for) and (;)
  
  So the first received line can be broken down thus:
  
  from nskntingx07p.mx.bigpond.com ([66.163.178.121])
  by nskntmtas06p.mx.bigpond.com with ESMTP
  id 20090406003140.hnm57.nskntmtas06p.mx.bigpond.com@nskntingx07p.mx.bigpond
  .com>
  for ; Mon, 6 Apr 2009 00:31:40 +0000
  

This is the information relating to the Bigpond mail server which is the last server in the chain. Note the ip address, there can be multiple Received lines and by checking the dns name in the From and By tokens, against the ip addresses in the chain you can see if someone is spoofing.

• DKIM-Signature : DomainKeys Identified Mail is a domain level authentication for email using public key cryptography.
• X-Mailer : sender's mailer software, in this case Yahoo web mail.

Then we have the header lines that are visible in most email messages, being:

• Date
• From
• Subject

Then there are references to the encoding (in this case MIME 1.0) and the content which could be plain/text ascii, but in this case is multipart/alternative, probably due to some coding in the signature as it is from Yahoo.

In summary the information we can glean from this email's header regarding, the user's email, the origin of a message and the path it took is as follows.

The email was written by Jason Radich using Yahoo mail web application. Using Network Tools to check the DNS against the IP address, the origin is confirmed as Yahoo. The message has three Received lines, but only seems to have gone through two mail servers, Yahoo and Bigpond. The first Received line I think is internal at Yahoo, as it doesn't have a full set of Tokens.

Probably went into overkill on this question having been away from my blog for nearly a month, but it seemed to require more investigation than the simplicity of the question implied. Very interesting to look at this metadata.