How to Choose the Right Email Infrastructure for Your Business

When it comes to sending high-volumes of email, there are seemingly countless providers to choose from. Most of the solutions on the market today offer either a cloud-based SMTP email relay solution or an on-premises MTA, but other options exist, too.

In order to determine which type of email infrastructure is right for your business, you’ll need to spend time assessing your goals with email, as well as your priorities. There is no one email delivery solution that meets the needs of all types of email senders, so let’s spend some time exploring the pros and cons of the various types of email infrastructure that are available to you.

What is Email Delivery Infrastructure, Anyway?

At a high level, think about email delivery infrastructure like plumbing: everyone uses it, but nobody really thinks about it unless it breaks.

Similarly, email delivery infrastructure is a highly complex system of moving parts that businesses rarely think about unless their lovingly crafted emails aren’t landing in the inbox.

From servers, domain name systems and IP addresses to click tracking, link rewriting, bounce management and feedback loop processing, there is a lot going on behind the scenes each time someone hits ‘Send’.

To learn more about how email infrastructure works, refer to our previous blog post.

Who Needs Email Infrastructure?

Quite honestly, every business who sends email.

There are countless ways a business can communicate with their customers and potential customers via email, including purchase confirmations and password resets, newsletters and sales offers, travel itineraries, customer support communications and billing statements, just to name a few examples.

And the type of infrastructure you use will depends on how many people you’re sending to, how often you’re contacting them, and how important it is for those emails to be delivered in a timely and secure way.

What Are My Options within Email Delivery Architecture Landscape?

From big-box omnichannel solutions to niche email providers focusing on a particular service or industry, choosing the right email delivery solution for your email program can feel overwhelming.

If you make the wrong choice, it can lead to sunken time and costs, frustration, and a limited ability to accomplish your goals.

The good news is that SocketLabs offers multiple solutions for email delivery infrastructure and services, so you can be sure that your email program is set to scale with minimal effort exactly when you need it to as your business grows. And these can be paired with our advanced reporting tools and expert services to meet your company’s unique needs.

So what types of email delivery infrastructure are available on the market today? And which one is right for you?

  • On-premises MTA (open sourced or commercially licensed)
  • Cloud-hosted MTA Service
  • Hybrid Cloud Sending

What to Consider When Choosing Your Email Infrastructure

As you’re planning your email program and getting setup, you’ll want to consider how important each of the following are to you:

Ease of Use

If you’re looking for something fast, reliable and easy to set up, the cloud may be your best fit. Cloud solutions allow you to plug in and start sending quickly, typically for a nominal monthly fee, and they handle all aspects of email delivery from bounce and subscriber management to traffic shaping and reporting for you. Whereas on-premises solutions require more time, effort, and cost to set up, and also require the owner (you) to maintain their performance over time.

Cloud providers also offer services and support to help with account setup, troubleshooting and deliverability questions along the way. In fact, you can sign up for a SocketLabs account and be sending in the next 5 minutes, if you want.

Note: Looking to get your email program up and running quickly with expert assistance? Start sending with our Free Trial. You get all of the core features you need to create the ultimate email program with none of the headaches. 


Do you really just want your email program to work without having to think about it? Particularly if you’re sending transactional emails such as password resets, purchase confirmations or any other time-sensitive content, making sure those emails arrive (and without delay) is table stakes.

Data Security and Compliance

If your business operates in a highly-regulated industry such as the medical or financial sector, you may require a solution that provides more security than what is possible within the cloud. Depending on where your business and email recipients are located, you may also need to consider the increasing regional regulatory pressures that are driving legislation such as GDPR (in Europe) and CCPA (in California).


Does your organization prefer capital costs or operating costs? Many cloud-hosted solutions are based on a CPM (Cost Per Mille/Thousand) model, keeping costs tied to sending volumes, which for most organizations is also strongly related to revenue. This ideally allows your email budget to grow in sync with revenues. But let’s face it: when you’re sending high volumes of emails, the CPM model simply does not scale. At some point, typically between 500 million and 1 billion per month, CPM costs start to eat into email ROI.

On the other hand, managing your own email infrastructure comes with several costs as well. But many are fixed on an annual basis, allowing your revenue growth to potentially outpace your email infrastructure costs. Most expenses related to on-premises MTAs will come from setting up and storing the physical servers in your location and hiring in-house staff to configure and then continually maintain your email infrastructure.

Flexibility and Advanced Configurations

If your company has a complex email program that is already sending high volumes (let’s say, above 500 million per month), or you have a team in-house who wishes to directly manage critical configuration tasks such as queue management, traffic shaping, deferral optimizations, real-time content and email header manipulation as well as other policy options, you may have a hard time finding a cloud MTA provider who allows the level of flexibility you desire. In these cases, an on-premises email solution might be right for you.

But be warned: this is not a decision to take lightly! Continuing with our plumbing analogy from earlier, consider that most people don’t build and maintain their own plumbing system full-time unless they’re a hotel or mega mansion.

Compliance and Abuse Reporting

If you’re setting up a multi-tenant environment where you’ll be managing the email activity of multiple senders, you’ll want to consider how you plan to manage abuse complaints and problematic senders within your network. Their actions can negatively impact sender reputation for other customers, making it harder for everyone to reach the inbox — also making it harder for you to retain customers and grow your business.

At SocketLabs, we provide data-driven solutions and guidance that allow you to manage the compliance process yourself, or offload it to our team of experts for handling. Learn more about our deliverability consulting services here.

What are the Benefits and Challenges of My Email Infrastructure Options?

Since there is no such thing as a one-size-fits-all email delivery solution, you’ll need to spend some time reviewing your goals with email and determining what you value most: ease of use, deliverability, scalability, customer support, cost, data security & compliance, flexibility & advanced configurations, or overall performance.

So let’s dig into the pros and cons of the various types of email infrastructure that are available to you. We’ve created a comprehensive comparison chart to highlight all of the benefits and challenges of cloud solutions vs on-premises MTAs, which you can check out here.

PDF Comparison Chart can be found here.

email infrastructure comparison

In the Cloud: API/SMTP Relay

Cloud-based email solutions allow businesses to jump right in to sending email, even when they have a small budget and little knowledge about email. Cloud solutions generally have an intuitive user interface, helpful documentation and APIs/SDKs/Code Libraries and offer the ability to integrate with other popular tools your company may be using as part of your larger marketing efforts.

Customer support teams are in place to help new customers get up and running quickly, and the subscription-based service model provides businesses with a straightforward approach to email that is easy to manage.

Primary Benefits of the Cloud

Ease of use

Unless email is your full-time focus, you’re likely trying to juggle a lot of other tasks in your day. The last thing you need to think about is how to configure a mail server, analyze your sending activity and worry about if your emails are going to the spam folder.

If you just want email to work without taking up a lot of your mental space, an SMTP email relay service in the cloud will do just that, plus provide you with support and email expertise to help if something goes amiss.

The cloud also provides businesses with a lower the barrier to entry for features that are normally limited to commercial MTAs such as intelligent delivery and managed traffic shaping, giving you a high likelihood of hitting the inbox with your emails.


Business is booming? No problem! Send as much email as you want to, when you want to. No need to spin up new servers on-prem when you’re a cloud customer.

Strong deliverability

While cloud technology can’t promise the reputation protection of an isolated on-premises solution, reputable cloud providers like SocketLabs thoroughly vet and monitor our customers to ensure strong reputation and email performance for all.

In addition to the typical analytics offered within a mailing platform’s dashboard, our proprietary StreamScore analyzes a variety of unique first-party and third-party data points to determine the overall health of your email program and helping you identify opportunities for improvement in four key areas: audience, engagement, sender reputation, and authentication.

We also take email optimization seriously, which is why we’re innovating our solutions to continually make email delivery easier for our customers. Just one example: we added Mail Transfer Agent Strict Transport Security (MTA-STS) for all cloud customers, automatically adding protection to the emails they send, with no actions or email expertise required on their part.

Support is offered to the masses

Email is complex, but it doesn’t have to feel that way. Most cloud providers offer customer support to assist with account set up, troubleshooting and deliverability concerns.

At SocketLabs, we offer customer support via chat, email and phone. In addition, all customers are eligible for our Deliverability and Managed Solutions, not just those sending millions per month. Have a question? Let’s talk about it

Primary Challenges of the Cloud

Deliverability can be outside of your full control

Not all cloud providers are of equal quality! If the vendor you’re working with doesn’t thoroughly vet their customers and take action to address problematic senders, this can result in your messages missing the inbox, even if you’re a good sender. Dedicated IPs can limit the risk of deliverability issues caused by other customers, but only if the majority of other customers are well behaved. At SocketLabs, we take anti-abuse very seriously, giving you the best chance of hitting the inbox. Consult your vendor’s Acceptable Use Policy (AUP) or contact their Support team to learn more about how seriously they take anti-spam and deliverability.

The CPM model doesn’t scale for high-volume senders

Your business and email program are growing (yay!), but so are your costs (…not so yay). We typically see that around the time a sender reaches 500 million to 1 billion emails per month, the CPM model breaks. If your company’s monthly volume is approaching this range or if you’ve already noticed that email costs are starting to eat into your revenue, it may be time to consider an alternative. Read on to see what else is available.

On-Premises MTA

Think about on on-premises email solution like buying your own car instead of taking a bus or taxi everywhere. Owning a car definitely has its advantages, but only if you’re willing to take on the responsibilities of driving, maintaining your vehicle and even just finding somewhere to park without racking up a glove box full of tickets (not that I’m speaking from experience here… 😇).

Unlike cloud-based email solutions where you can hop on and off the bus as you see fit, getting started with an on-premises email solution comes with a lot of up-front work and costs to set up. You’ll also need to have in-house experts to configure, secure and maintain your infrastructure, develop reporting and automation functions, and generally keep your email car driving safely. But once you’re up and running, getting around town (aka sending high volumes of emails that perform well) can become easier and more cost-effective the more you drive.

Primary Benefits of On-Prem

Greater security

On-premises email infrastructure is the most secure option available. It’s ideal for businesses operating in highly-regulated industries where security and compliance with regulations such as CASL (in Canada), GDPR (in Europe), CCPA (in California), etc. is a priority.

More control

Your in-house team has total control over security and configuration, allowing you to fine-tune your email infrastructure to your specific needs. You get to decide everything from where your servers are located and who has access, to what anti-spam software you’ll use and how you should handle traffic shaping. Left within capable hands, on-prem solutions provide an opportunity to unlock email performance that might not be achievable within a cloud environment.

On-premises email sending environments are not shared with other senders, removing the risk of outside impacts to deliverability.

Access to a more holistic approach to marketing

Email performance should never be viewed within a silo when it’s part of a larger marketing experience you’re delivering to customers. Unlike cloud solutions which can be limited the handful of integrations they offer, on-prem solutions can connect to other on-premises data sources, as well as integrate with any CRM, financial software or BI tools your company may be using. Embrace a more holistic approach to marketing by connecting all of the dots within your customers’ journey.

Primary Challenges of On-Prem


Before you can start sending emails, you’ll need to purchase your email server(s), install them in your physical location, and then have your team configure them. And your job is not finished when you’ve gotten your on-prem servers installed. Deliverability issues can arise if MTAs are not continually managed, so it’s important to have knowledgeable IT specialists on staff to configure the MTAs to your specific needs and also regularly tune them to adjust to changes in delivery.

The upside of on-prem email infrastructure is that costs are fixed on an annual basis, allowing your revenue growth to potentially outpace costs associated with your email infrastructures.


As your company’s email volume grows, you will eventually need to invest in more on-prem servers to support the additional volume. This requires additional installation (and cost) for on-prem email senders. While this necessary step can act as a temporary speed bump prohibiting the immediate scalability that is offered within the cloud, the investment may prove to be more cost-efficient when your email volumes scale beyond 500 million to 1 billion per month.

Hybrid Cloud Sending

As you may be realizing, there’s no obvious winner in the competition between cloud and on-premises solutions. Choosing the right email infrastructure for your business requires a close look at your goals, priorities, and capabilities as an organization.

Some of the challenges our customers face with their email infrastructure include:

  • If you’ve been sending from on-premises infrastructure all this time: what to do when the rest of your organization’s stack moves to the cloud? The MTAs are normally being left behind because you’re not comfortable risking your performance… at least not yet. 😰
  • If you’ve been sending from the cloud and your email costs have started eating into your revenue, or you’ve simply outgrown the capabilities of your current provider: when is the right time to lift and shift everything to on-prem?
  • If you’ve been using multiple providers (including on-prem and cloud solutions), how can you centralize your management flow to improve performance and ease the burden of your in-house marketing, compliance and deliverability teams?

Many of us at SocketLabs have been working in email for 10+ years, and we’ve faced these challenges ourselves as practitioners. And so, now that we’ve added email nerds to every department (including CEO), we asked ourselves, “What kind of email delivery infrastructure would we prefer to use as senders?” And the conclusion we came to (just as the little girl in the Old El Paso hard- and soft-shelled tacos commercial did) was: “Why don’t we have both?”

And so, we set to work creating our hybrid cloud email delivery solution, which allows us to offer managed email infrastructure by combining the benefits of both traditional cloud and on-premises email solutions — without being chained to a CPM model. You have the ability to use the cloud for some services while keeping others in-house. It’s the best of all email worlds, if you will.

Created by email nerds, for email nerds. All for the love of email. 💌

Primary Benefits of Hybrid Cloud Solution

Ensure security where it’s needed most

By hosting part of your email universe on-premises in your own location, you can ensure any personally identifiable information (PII) you’re storing has the highest chance of remaining secure.

Maintain performance on business-critical communications while you migrate

Whether your on-premises servers are following the rest of your business to the cloud, or you’re migrating aspects of your business to operate on-premises, our team of implementation and delivery experts guide you through the migration process, ensuring minimal disruptions to email delivery.

Our hybrid cloud solution allows you to move an open-sourced or commercially-licensed MTA to a cloud-compute instance while limiting interruptions in email delivery as your company scales.


Unlike other hybrid solutions on the market today, ours is not associated with a CPM model in order to access performance reporting.


When email volume and revenue are growing, the last thing you want to do is change anything about your email infrastructure. Life is good! But eventually, the operating costs of the traditional, cloud-based CPM model will eat into your profits if you don’t plan for your future success. This is particularly true as email volumes edge above the 1 billion per month mark.

Our true Hybrid Cloud Sending model (currently in Beta) gives you the ability to send partially from the cloud and partially on-premises. This means you don’t have to do a giant lift and shift when your email program outgrows the cloud. Move incrementally and painlessly, on your terms and timeline, all within the same SocketLabs house.

Get that redundancy provider you’ve been losing sleep over for years (finally)

 🎉Securing a back-up for your email program is typically on most IT Admins’ list of things to do to prevent losses that occur due to server downtime, deliverability issues, etc. But it’s a task that typically never makes its way to the top of a priority list until something devastating has happened, resulting in major losses or expensive emergency fixes at the 11th hour.

Total Control where you want it, and managed support everywhere else

By embracing our hybrid cloud technology, you can enjoy a customized level of control over configuration, allowing you to tune it to your specific needs, while resting easy with the knowledge that we’ll be monitoring, and can notify you and/or take necessary action on your behalf.

Critical mail streams will not be shared with other senders, removing the risk of outside impacts on delivery and deliverability – while less critical mail streams can scale immediately as needed to meet business objectives.

Primary Challenges of Hybrid Cloud

Not as secure as a full on-premises solution

Yet the aspects you’ll be hosting in the cloud are typically non-critical (such as marketing newsletters), so they likely do not need to be moved to on-prem unless you want to.


On-premises servers will still be costly to setup and store. DevOps processes will be easier to maintain than a fully on-prem solution, but you’ll likely still require some level of in-house expertise to configure and tune your on-premises MTAs.

Interested in learning more about our hybrid cloud sending solution? Let’s talk.

While choosing the right email infrastructure for your business can be an overwhelming process, you don’t have to go through this alone. There are vendors out there (like SocketLabs) who can meet the email needs of a wide variety businesses by providing multiple solutions for email delivery infrastructure.

We’re happy to chat with you about your email needs and answer any questions you may have. Because choosing email infrastructure is hard. And scaling email infrastructure as your business grows is even harder. Let’s do this together!

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