Marek Loder
Customer Success
Email Authentication
What you need to know
Patrick Graham
Customer Success
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• Spend my days at Postmark onboarding new clients
• Work out of our headquarters here in Philadelphia
• Big fan of the great outdoors
• Newly minted private pilot
• Music and coffee aficionado.
• I spend my days at Postmark troubleshooting
technical problems for our customers
• Work remotely from the Pacific Northwest.
Marek Loder
Patrick Graham
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What is Postmark?
A fast & reliable transactional-only email
platform for web applications
Your customers expect application emails
to arrive immediately, not eventually.
Reaching the inbox isn’t enough
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1. What are the authentication methods and how do they work?
2. Why are they important for you?
What are you going to learn?
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Image source: https://www.flickr.com/photos/eelssej_/413385838
Why do I need email authentication?
‘From Address’:
Return-Path:
Who the message was sent from
Where the message was sent from
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Github’s SPF Record
v=spf1 ip4:192.30.252.0/22 include:_spf.google.com include:mail.zendesk.com ~all
This is an SPF record
Defines an IP range
Google and ZenDesk
mail servers
Accept all mail. (Soft Fail)
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Github’s SPF Record
v=spf1 ip4:192.30.252.0/22 include:_spf.google.com include:mail.zendesk.com ~all
This is an SPF record
Defines an IP range Accept all mail. (Soft Fail)
Google and ZenDesk
mail servers
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No content
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SPF Gotchas…
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Only use one SPF record
v=spf1 include:_spf.google.com ~all
TXT
v=spf1 include:mail.zendesk.com ~all
TXT
v=spf1 include:_spf.google.com
include:mail.zendesk.com ~all
TXT
SPF Gotchas
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Only 10 lookups
SPF Gotchas
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2
Domain Keys Identified Mail
DKIM
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1. Private key
2. Public key
3. Signature
DKIM Components
3
Domain-based Message
Authentication and Conformance
DMARC
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DMARC
Special DMARC
subdomain
_dmarc.gmail.com
v=DMARC1\; p=none\; rua=mailto:[email protected]
TXT
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DMARC
v=DMARC1\; p=none\; rua=mailto:[email protected]
_dmarc.gmail.com
This is a DMARC record Reporting
Policy
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DMARC
v=DMARC1\; p=none\; rua=mailto:[email protected]
_dmarc.gmail.com
This is a DMARC record Reporting
Policy
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DMARC Tool
A free tool to monitor & implement DMARC
dmarc.postmarkapp.com
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Checking Validity
Check DKIM, SPF, and
DMARC validity in Gmail
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SPF passing and DMARC SPF passing
are not the same thing.
DMARC SPF alignment requires that the From address
domain matches the Return-Path domain
DMARC - SPF alignment gotcha
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SPF Domain-based way to say what IPs are
allowed to send email for you.
DKIM Message-based signatures to verify your
email is unmodified.
DMARC Domain-based way to tell receivers how to
handle authentication failures for your domain.
Email Authentication Methods
Unprecedented Troubleshooting
45 days of
email activity
Search all
your messages
Detailed message
events
Advanced
filtering
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Detailed message events,
grouped by recipient
Full content previews
(HTML & Plain Text)
Message overview
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Customer support that’s human
Made the switch to @postmarkapp today.
The customer service and delivery rates are
awesome.
Samuel Goudie
“ Postmark has stellar customer service. I
don't think I have ever waited more than a
few minutes for a response to an email.
Christopher Dundy
“
Ashley Dana Marek Patrick
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DMARC Reports MailMason SpamCheck StyleMerge MailBrush
Templates Mustachio Webhooks MailHandler
postmarkapp.com/labs
Check out our free & open source tools at…
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Part of the family.
postmarkapp.com
Questions?
Email [email protected]
@postmarkapp