Peter Lord
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About me, Peter Lord
Talks - https://plord.co.uk/talks/
Please use https://u3acommunities.org/computing-feedback for any talk feedback
Agenda
Overview
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Compose Email
Send to harry@their.com
mail.my.com
mail.their.com
Route Email
Fetch Email
Compose Email
Breakdown of an email message
From: george@my.com
To: harry@their.com
Subject: Test
Hi Harry. All okay ?
Headers
Blank line
Message
Breakdown of an email message - headers
Breakdown of an email message - message
From: george@my.com
To: harry@their.com
Subject: Test
Content-Type: multipart/alternative;
boundary="--==_mimepart_1234"
----==_mimepart_1234
Content-Type: text/plain;
charset=UTF-8
Content-Transfer-Encoding: quoted-printable
Hi Harry. All okay ?
----==_mimepart_1234
Content-Type: text/html;
charset=UTF-8
Content-Transfer-Encoding: quoted-printable
<p>Hi Harry. All okay ?</p>
----==_mimepart_1234--
Overview
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Compose Email
Send to harry@their.com
mail.my.com
mail.their.com
Route Email
Fetch Email
Sending with Simple Mail Transport Protocol (SMTP)
$ telnet email.my.com 25
Trying 192.168.175.12...
Connected to arm3.
Escape character is '^]'.
220 myemail.com ESMTP Postfix
HELO my.com
250 myemail.com
MAIL FROM:<george@my.com>
250 2.1.0 Ok
RCPT TO:<harry@their.com>
250 2.1.5 Ok
DATA
354 End data with <CR><LF>.<CR><LF>
To: harry@their.com
From: george@my.com
Subject: Test
hello !
.
250 2.0.0 Ok: queued as C74086C0647
QUIT
221 2.0.0 Bye
Overview
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Compose Email
Send to harry@their.com
mail.my.com
mail.their.com
Route Email
Fetch Email
Routing with Domain Name Service (DNS)
$ nslookup
> server 8.8.8.8
Default server: 8.8.8.8
Address: 8.8.8.8#53
> set type=mx
> their.com
Server: 8.8.8.8
Address: 8.8.8.8#53
Non-authoritative answer:
their.com mail exchanger = 10 mail.their.com.
their.com mail exchanger = 10 mail2.their.com.
Overview
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Compose Email
Send to harry@their.com
mail.my.com
mail.their.com
Route Email
Fetch Email
Receiving email with POP3 / IMAP4
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mail.their.com
Post Office Protocol (POP)
Message
Message
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Internet Message Access Protocol (IMAP)
Internet Message Access Protocol (IMAP)
Message
Folders
Filters
WebMail
Spam filtering
SPF, DKIM and DMARC
DMARC and SPF
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Compose Email
Send to harry@their.com
mail.my.com
mail.their.com
Route Email
Fetch Email
Add DKIM header
Validate DKIM
Validate SPF
Apply DMARC
Reject, Quarantine, or Pass
Netiquette
Posting style
I have been following the discussion about the new product line. Here are my thoughts.
Joe wrote:
> Will our prices be competitive?
That may not be a problem for now, we still have a quality edge.
> We do not have enough trained people on the West Coast. We have many
> new employees but they do not know our products yet.
We can bring them here for a crash training course.
Mary wrote:
> We still do not have a clear marketing plan.
Peter, would you take charge of that? Let me know if you need help.
On the whole, I am quite optimistic. It looks like we will be shipping
the basic system before the end of this quarter.
Nancy
No problem. 6pm it is then.
Jim
-------- Original Message --------
From: Danny <danny@example.com>
Sent: Tuesday, October 16, 2007 10:01 AM
To: Jim <jim@example.com>
Subject: RE: Job
Whoa! Hold on. I have a job scheduled at 5:30 which mails out
a report to key tech staff. Could you please push it back an hour?
Danny
-------- Original Message --------
From: Jim <jim@example.com>
Sent: Tuesday, October 16, 2007 9:40 AM
To: Danny <danny@example.com>
Subject: Job
I'm going to suspend the mail service for approx. thirty
minutes tonight, starting at 5pm, to install some updates
and important fixes.
Jim
At 10.01am Wednesday, Danny wrote:
> At 9.40am Wednesday, Jim wrote:
>> I'm going to suspend the mail service for approx. thirty
>> minutes tonight, starting at 5pm, to install some updates
>> and important fixes.
> Whoa! Hold on. I have a job scheduled at 5:30 which mails out
> a report to key tech staff. Could you push it back an hour?
>
> By the way, which systems will be updated? I had some network
> problems after last week's update. Will I have to reboot?
No problems. 6pm it is then.
Basically, I will update our WWW server and firewall.
No, you won't have to reboot.
On Thursday, Jim wrote:
> The movie clearly adds a sense of menace to the story
> which is not present in the original book.
> [...claim that the darker tone weakens the movie...]
I disagree. The darker tone works well, once one understands
the two are aimed at different audiences.
Because it messes up the order in which people normally read text.
Why is top-posting such a bad thing?
Top-posting.
What is the most annoying thing in e-mail?
Subaddresses and disposable addresses
Proof of delivery
Tools
References