Tag Archives: SES

How to implement multi tenancy with Amazon SES

Post Syndicated from satyaso original https://aws.amazon.com/blogs/messaging-and-targeting/how-to-manage-email-sending-for-multiple-end-customers-using-amazon-ses/

In this blog post, you will learn how to design multi-tenancy with Amazon SES, as well as the fundamental best practices for implementing a multi-tenant architecture that can effectively handle bulk the email sending needs of your downstream customers.

Amazon Simple Email Service (SES) is utilized by customers across various industries to send emails to their recipients. Often, they need to send emails on behalf of their downstream customers or for other business divisions. Organizations commonly refer to these use cases as “multi-tenant email sending practices. To implement email sending multi-tenancy practices (i.e. to send bulk emails on behalf of end customers), Amazon SES customers need to adopt an architecture that enables them to effectively meet the email sending needs of thousands of downstream customers while also ensuring that the email sending reputation of each customer or the tenant is isolated.

Use cases

  1. Onboard multiple brands from different Business units (BUs) with different domains.
  2. Separate marketing and transaction tenants.
  3. ISV Customer’s requirement to segregate email sending reputation of their end customers.
  4. Domain management via configuration sets.
  5. Track individual customer’s email sending repurataion and control their email sending process.

Prerequisites

For this post, you should be familiar with the following:

Solution Overview

In the email ecosystem, domain and IP reputation are critical in getting emails delivered to the inbox. Tenants in a multi-tenant scenario might be unique businesses or an internal team (eg marketing team, customer service team and so on). Because the maturity of each tenant varies greatly, implementing a multi-tenant environment may be increasingly complicated and difficult. While one tenant may have a well-validated and highly-engaged recipient list, another tenant may have an untrusted email recipient list, and sending emails to such email addresses may result in bounces or spam, lowering the IP and domain reputation. So, organizations have to build safe guards to prevent an unsophisticated sender or a bad actor from impacting the other tenants.

To better understand multi-tenancy, let us first look at how Amazon SES sends emails. Any emails sent via Amazon SES to end users are sent using IP addresses that have been mapped within Amazon SES. Amazon SES offers two types of IP addresses: shared IP addresses and dedicated IP addresses. (Currently Amazon SES offers two kinds of dedicated IPs, which are 1/ Standard dedicated IPs, 2/ Managed dedicated IPs). Shared IPs are shared across many SES customers, and all your emails are sent using shared IP addresses by default unless you have requested for dedicated IPs. Dedicated IP addresses/addresses are designated for a single customer or tenant, where the tenant might be a business unit within the customer’s own eco system or a downstream customer of an ISV.

If a customer is using shared IPs to send email via SES and trying to achieve multi tenancy, then they can do so to segregate the business functions of multiple tenants such as tenant tagging, SES event destination routing, cost allocation for each tenant, and so on; but it won’t help to manage or isolate email sending reputation from one tenant to another. This is because; these shared IPs are mapped to an AWS region and incase one rogue tenant is trying to send spam emails then it will impact other customers in the same region who are using same set of shared IPs.

If you are an Amazon SES user and wish to separate the reputation of one end-customer from another then dedicated IPs are the ideal solution. Dedicated IP or Dedicated IPs (also known as dedicated IP pool) can be assigned to a tenant, and the email sending reputation for that tenant can be readily isolated from that of another tenant. If tenant one is a problematic sender and internet service providers (ISPs) such as Gmail, Hotmail, Yahoo and, so on, flags the respective domain or IPs, the reputation of the other tenants’ domains and IPs are unaffected since they are mutually exclusive.

Amazon SES supports multi-tenancy primarily through two constructs: 1/configuration sets, 2/Dedicate IP pools. Configuration sets are setup rules that are applicable to your verified identities, whereas  dedicated IP pool is to group dedicated IPs into a pool, which can then be mapped to a configuration set, such that the respective Identity/Identities may only utilize the same IP Pool without affecting other tenants. Let’s now witness a simplified architecture view.

Amazon SES multi tenancy using a single AWS account

Multi tenancy using a single AWS account

In this architecture, if you notice tenant 1, tenant 2 and tenant 3 are using the distinct configurations with respective dedicated IPs while tenant 4 is using shared IPs. i.e. the tenants can chose which configuration sets needs to be used for their domain. This provides customers capability to achieve multi tenancy.

Amazon SES multi tenancy – best practices

Always proactively reach out to your account team or raise a support case under “service limit increase” category informing that you will be sending on behalf of tens of thousands of customers. This will help AWS in rightly setup limits within your account and be cognizant of your sending patterns.

While the architecture described above will most of the time help Amazon SES users manage multiple end customers effectively, in rare cases; Amazon SES users may receive a notification from AWS support stating that their Amazon SES account is being reviewed. This indicates that your Amazon SES account is being used to send problematic email to end recipients, or that the account has been paused (if you haven’t reacted proactively upon controlling the faulty senders within the review timeframe), which means you can’t send email from your SES account because your spam or complaint rate has exceeded a certain threshold. These type of situations occurs because, Amazon SES sanitization process is implemented at the AWS account level by default. So, even if any of the tenants using a dedicated IP or a dedicated IP pool and their spam or complaint rates exceed the approved SES limit, Amazon SES sends a notification to the account admin, flagging the concern in their account. In such cases, it is recommended to implement a process known as “automatically pausing email sending for a configuration set“. You can configure Amazon SES to export reputation metrics that are specific to emails that are sent using a specific configuration set to Amazon CloudWatch. You can then use these metrics to create CloudWatch alarms that are specific to those configuration sets. When these alarms exceed certain thresholds, you can automatically pause the sending of emails that use the specified configuration sets, without impacting the overall email sending capabilities of your Amazon SES account.

If you are an Enterprise ISV customer and you have tens of thousands of downstream customers then there is a possibility that you will hit Amazon SES provided maximum quota. In those scenarios you have two options; 1/ Ask for an exception for your AWS SES account – In this approach, you need to request AWS to increase your quota applicable for the existing account to a higher threshold and depending upon your previous usage and reputation AWS shall increase your account limit to accommodate more customers/tenants. To do this you need to raise an AWS support case under “service limit increase” and present your requirement on why you want to increase your Amazon SES account quota to a higher limit. There is no guaranty that the exception will always be granted. If your exception request is denied, you must proceed to the second option, which is to 2/ segment your customers across multiple AWS accounts. In this approach, you must calculate your customer base ahead of time and distribute your downstream customers across multiple accounts within the same AWS region in order to set up their email sending mechanism using SES. To better understand option 2, refer to the architecture diagram below.

Amazon SES multi tenancy using multiple AWS account

Multi tenancy using multiple AWS account

In the above architecture various tenants are connecting to Amazon SES in different AWS accounts to implement multi tenancy. Email event responses can be taken back to a central data lake located in the same AWS region or in different region. Furthermore, as shown in the diagram above, all AWS accounts mapped to different tenants are under a Parent AWS account; this hierarchical structure is known as AWS Organizations. it is recommended to use AWS Organizations which enables you to consolidate multiple AWS accounts into an organization that you create and centrally manage. It helps in security and compliance guide lines, managing consolidated billing for all the child accounts.

Conclusion

Appropriate multi-tenancy implementation within Amazon SES not only helps you manage end-customer reputation but also aids in tracking usage of each user independently from one another. In this post, we have showcased how Amazon SES users can utilize Amazon SES to manage large number of end customer, what are the design best practices to implement multi-tenant architecture with Amazon SES.

Satyasovan Tripathy works at Amazon Web Services as a Senior Specialist Solution Architect. He is based in Bengaluru, India, and specialises on the AWS customer developer service product portfolio. He likes reading and travelling outside of work.

 

Choosing the Right Domain for Optimal Deliverability with Amazon SES

Post Syndicated from komaio original https://aws.amazon.com/blogs/messaging-and-targeting/choosing-the-right-domain-for-optimal-deliverability-with-amazon-ses/

Choosing the Right Domain for Optimal Deliverability with Amazon SES

As a sender, selecting the right domain for the visible From header of your outbound messages is crucial for optimal deliverability. In this blog post, we will guide you through the process of choosing the best domain to use with Amazon Simple Email Service (SES)

Understanding domain selection and its impact on deliverability

With SES, you can create an identity at the domain level or you can create an email address identity. Both types of verified identities permit SES to use the email address in the From header of your outbound messages. You should only use email address identities for testing purposes, and you should use a domain identity to achieve optimal deliverability.

Choosing the right email domain is important for deliverability for the following reasons:

  • The domain carries a connotation to the brand associated with the content and purpose of the message.
  • Mail receiving organizations are moving towards domain-based reputational models; away from IP-based reputation.
  • Because the email address is a common target for forgery, domain owners are increasingly publishing policies to control who can and cannot use their domains.

The key takeaway from this blog is that you must be aware of the domain owner’s preference when choosing an identity to use with SES. If you do not have a relationship with the domain owner then you should plan on using your own domain for any email you send from SES.

Let’s dive deep into the technical reasons behind these recommendations.

What is DMARC?

Domain-based Message Authentication, Reporting, and Conformance (DMARC) is a domain-based protocol for authenticating outbound email and for controlling how unauthenticated outbound email should be handled by the mail receiving organization. DMARC has been around for over a decade and has been covered by this blog in the past.

DMARC permits the owner of an email author’s domain name to enable verification of the domain’s use. Mail receiving organizations can use this information when evaluating handling choices for incoming mail. You, as a sender, authenticate your email using DKIM and SPF.

  • DKIM works by applying a cryptographic signature to outbound messages. Mail receiving organizations will use the public key associated with the signing key that was used to verify the signature. The public key is stored in the DNS.
  • SPF works by defining the IP addresses permitted to send email as the MAIL FROM domain. The record of IP addresses is stored in the DNS. The MAIL FROM domain is not the same domain as the domain in the From header of messages sent via SES. It is either domain within amazonses.com or it is a custom MAIL FROM domain that is a subdomain of the verified domain identity. Read more about SPF and Amazon SES.

A message passes the domain’s DMARC policy when the evaluation DKIM or SPF indicate that the message is authenticated with an identifier that matches (or is a subdomain of) the domain in the visible From header.

How can I look up the domain’s DMARC policy?

You must be aware of the DMARC policy of the domain in which your SES identities reside. The domain owner may be using DMARC to protect the domain from forgery by unauthenticated sources. If you are the domain owner, you can use this method to confirm your domain’s current DMARC policy.

You can look up the domain’s DMARC policy in the following ways:

  • Perform a DNS query of type TXT against the hostname called _dmarc.<domain>. For example, you can use the ‘dig’ or ‘nslookup’ command on your computer, or make the same query using a web-based public DNS resolver, such as https://dns.google/
  • Use a 3rd party tool such as:

https://tools.wordtothewise.com/dmarc/
https://mxtoolbox.com/dmarc.aspx
https://dmarcian.com/dmarc-inspector/

The “p” tag in the DMARC record indicates the domain’s policy.

How does the domain’s policy affect how I can use it with SES?

This section will cover each policy scenario and provide guidance to your usage of the domain with SES.

Policy How to Interpret You have verified the domain identity with EasyDKIM You have only email address identities with the domain
No DMARC record The domain owner has not published a DMARC policy. They may not yet be aware of DMARC There is no DMARC policy for mail receiving organizations to apply. Your messages are authenticated with DKIM, so mail receiving organization may leverage a domain-based reputational model for your email. There is no DMARC policy for mail receiving organizations to apply. Your messages are not authenticated, so reputation remains solely based on IP.
none The domain owner is evaluating the DMARC reports that the mail receiving organizations send to the domain owner, but has requested the mail receiving organizations not use DMARC policy logic to evaluate incoming email. There is no DMARC policy for mail receiving organizations to apply. Your messages are authenticated with DKIM, so mail receiving organization may leverage a domain-based reputational model for your email. There is no DMARC policy for mail receiving organizations to apply. Your messages are not authenticated, so reputation remains solely based on IP.
quarantine The domain owner has instructed mail receiving organizations to send any non-authenticated email to a quarantine or to the Junk Mail folders of the recipients. Your messages are authenticated with DKIM and will not be subjected to the domain’s DMARC policy. Mail receiving organizations may not deliver your messages to the inboxes of your intended recipients.
reject The domain owner has instructed mail receiving organizations to reject any non-authenticated email sending from the domain. Your messages are authenticated with DKIM and will not be subjected to the domain’s DMARC policy. Mail receiving organizations may reject these messages which will result in ‘bounce’ events within SES.

Other considerations

If the domain has a none or quarantine policy, you must be aware that the domain owner may have a plan to migrate to a more restrictive policy without consulting with you. This will affect your deliverability in the form of low inboxing/open rates, or high bounce rates. You should consult with the domain owner to determine if they recommend an alternative domain for your email use case.

Not all mail receiving organizations enforce DMARC policies. Some may use their own logic, such as quarantining messages that fail a reject policy. Some may use DMARC logic to build a domain-based reputational model based on your sending patterns even if you do not publish a policy. For example, here is a blueprint showing how you can set up custom filtering logic with SES Inbound.

If you have verified the domain identity with the legacy TXT record method, you must sign your email using a DKIM signature. The DKIM records in the DNS must be within the same domain as the domain in the From header of the messages you are signing.

If you have the domain identity verified with EasyDKIM and you also have email address identities verified within the same domain, then the email address identities will inherit the DKIM settings from the domain identity. Your email will be authenticated with DKIM and will not be subjected to the domain’s DMARC policy.

Can I use SPF instead of DKIM to align to the domain’s DMARC policy?

Messages can also pass a DMARC policy using SPF in addition to DKIM. This is enabled through the use of a custom MAIL FROM domain. The custom MAIL FROM domain needs to be a subdomain of the SES identity and the SES domain identity’s DMARC policy must not be set to strict domain alignment due to the way SES handles feedback forwarding. The domain owner enables a custom MAIL FROM domain by publishing records in the DNS. There is no way to authenticate email without publishing records in the DNS. Read Choosing a MAIL FROM domain to learn more.

The recommended approach is to use EasyDKIM primarily, and optionally enable a custom MAIL FROM domain as an additive form of authentication.

What should I do if I am not the domain owner?

The process of enabling DKIM and SPF authentication involves publishing DNS records within the domain. Only the domain owner may modify DNS for their domain. If you are not the domain owner, here are some alternative solutions.

Option 1: Segregate your email sending programs into subdomains.

This option is best for people within large or complex organizations, or vendors who are contracted to send email on behalf of an organization.

Ask the domain owner to delegate a subdomain for your use case (e.g. marketing.domain.example). Many domain owners are willing to delegate use of a subdomain because allowing for multiple use cases on a single domain becomes a very difficult management and governance challenge.

Through the use of subdomains they can segregate your email sending program from the email sent by normal mailbox users and other email sending programs. This also gives mail receiving organizations the ability to create a reputational model that is specific to your sending patterns, which means that you do not need to inherit any negative reputation incurred by others.

Option 2: Use a domain in which you are the domain owner.

This option is best if you have end-customers (or tenants) who have email addresses within domains which have domain owners that will not allow any form of delegation to you.

Use your own domain as the domain identity, and use subdomains within your domain to distinguish your end-customers from each other (e.g. tenant1.yourdomain.example, tenant2.yourdomain.example, tenant3.yourdomain.example, …). Amazon WorkMail uses this strategy for the awsapps.com domain.

This gives you complete control over the domain as well as your reputation. Use subdomains to segregate reputation between your end-customers if you have a multi-tenant business model.

Here are some additional suggestions to make your email more personable while remaining aligned to the domains’ DMARC policies.

  • You may format the From header of your outgoing messages so that the display name clearly reflects the name of the message author.

From: “John Doe via My App” <[email protected]>

  • Set the Reply-to header of your outbound messages so that when recipients reply, the return messages will go to the intended recipient.

Reply-to: [email protected]

What should I do if the domain is already being used for a different email sending program?

From a deliverability perspective, it is beneficial to compartmentalize your sending into different domains, or subdomains, for different email sending programs. That will limit the reputational blast radius if something were to go wrong with one campaign. Consider using different subdomains for each sending program. For example:

  • marketing.domain.example
  • receipts.domain.example

DMARC was designed for marketing and transactional email use cases, so it is good practice to publish ‘reject’ DMARC policies for those subdomains. Having a strong policy doesn’t give a free pass into recipient inboxes, but it allows the mail receiving organization to know what to do with messages that aren’t authenticated, which can lead to better trust. Building trust is the best way to gain a positive reputation.

If the domain is used by normal users for day-to-day correspondences, the domain owner should be very careful about publishing a DMARC policy because it is known to create interoperability issues with mailing lists and other email providers. Many of these email domains may never publish a ‘reject’ DMARC policy. For new email sending programs, you should strongly consider using a subdomain rather than any domain that is being used for user correspondences.

Conclusion

To ensure optimal deliverability with Amazon SES, it’s essential to be aware of the domain owner’s preferences and use a domain identity for outbound messages. Keep in mind that email address identities should only be used for testing purposes or with domains without DMARC policies. Domain owners can use subdomains to segregate email sending programs, making management and governance easier while allowing mail receiving organizations to build isolated reputational models.

By following the recommendations in this blog, you’ll be better prepared to align with the domain owner’s preferences, achieve higher deliverability rates for your authenticated outbound email, and be compatible with future DMARC developments.

Opt-in to the new Amazon SES console experience

Post Syndicated from Simon Poile original https://aws.amazon.com/blogs/messaging-and-targeting/amazon-ses-console-opt-in/

Amazon Web Services (AWS) is pleased to announce the launch of the newly redesigned Amazon Simple Email Service (SES) console. With its streamlined look and feel, the new console makes it even easier for customers to leverage the speed, reliability, and flexibility that Amazon SES has to offer. Customers can access the new console experience via an opt-in link on the classic console.

Amazon SES now offers a new, optimized console to provide customers with a simpler, more intuitive way to create and manage their resources, collect sending activity data, and monitor reputation health. It also has a more robust set of configuration options and new features and functionality not previously available in the classic console.

Here are a few of the improvements customers can find in the new Amazon SES console:

Verified identities

Streamlines how customers manage their sender identities in Amazon SES. This is done by replacing the classic console’s identity management section with verified identities. Verified identities are a centralized place in which customers can view, create, and configure both domain and email address identities on one page. Other notable improvements include:

  • DKIM-based verification
    DKIM-based domain verification replaces the previous verification method which was based on TXT records. DomainKeys Identified Mail (DKIM) is an email authentication mechanism that receiving mail servers use to validate email. This new verification method offers customers the added benefit of enhancing their deliverability with DKIM-compliant email providers, and helping them achieve compliance with DMARC (Domain-based Message Authentication, Reporting and Conformance).
  • Amazon SES mailbox simulator
    The new mailbox simulator makes it significantly easier for customers to test how their applications handle different email sending scenarios. From a dropdown, customers select which scenario they’d like to simulate. Scenario options include bounces, complaints, and automatic out-of-office responses. The mailbox simulator provides customers with a safe environment in which to test their email sending capabilities.

Configuration sets

The new console makes it easier for customers to experience the benefits of using configuration sets. Configuration sets enable customers to capture and publish event data for specific segments of their email sending program. It also isolates IP reputation by segment by assigning dedicated IP pools. With a wider range of configuration options, such as reputation tracking and custom suppression options, customers get even more out of this powerful feature.

  • Default configuration set
    One important feature to highlight is the introduction of the default configuration set. By assigning a default configuration set to an identity, customers ensure that the assigned configuration set is always applied to messages sent from that identity at the time of sending. This enables customers to associate a dedicated IP pool or set up event publishing for an identity without having to modify their email headers.

Account dashboard

There is also an account dashboard for the new SES console. This feature provides customers with fast access to key information about their account, including sending limits and restrictions, and overall account health. A visual representation of the customer’s daily email usage helps them ensure that they aren’t approaching their sending limits. Additionally, customers who use the Amazon SES SMTP interface to send emails can visit the account dashboard to obtain or update their SMTP credentials.

Reputation metrics

The new reputation metrics page provides customers with high-level insight into historic bounce and complaint rates. This is viewed at both the account level and the configuration set level. Bounce and complaint rates are two important metrics that Amazon SES considers when assessing a customer’s sender reputation, as well as the overall health of their account.

The redesigned Amazon SES console, with its easy-to-use workflows, will not only enhance the customers’ on-boarding experience, it will also change the paradigms used for their on-going usage. The Amazon SES team remains committed to investing on behalf of our customers and empowering them to be productive anywhere, anytime. We invite you to opt in to the new Amazon SES console experience and let us know what you think.