Why should you use Dedicated Email Marketing Infrastructure?

How Much Email Does Your Company Send?

  • A Hundred a day?
  • A Thousand a day?
  • A Million a day?
  • More?

Believe it or not, many organizations send several million emails a day, and enterprises, large online retailers, social networks and gaming sites often send as much as a billion a month. In the case of social networks, a few send as many as a billion emails a day. No matter how much companies send, they all send for the same reason: They have a community of customers or users, and these companies need to keep their communities engaged and in-the-know. Why? Because a disengaged community is no community at all, and a disengaged customer base is not going to be your customer base for long.

Is it easy to send high volumes of email? Yes and no. It’s easy to do, but the way you do it is what matters. Large volumes of mail can be expensive to deploy. Worse, large volumes of mail may be perceived as spam by ISPs. If done incorrectly, high-volume sending can drain your resources and your revenue, and provide no value at all to your customers. How can you keep your customers happy and engaged if your message never makes it to the intended inbox?

Here are four steps you need to take to do it right:

1. Optimize Your Sending Platform

As a sender, you have the option of using a cloud based email service provider (ESP) or using your own dedicated sending infrastructure service like MailBrainiers, and you have to choose the best model for your situation. MailBrainiers provide not only infrastructure but also expertise, to handle the myriad details of sending email for their clients. This enables companies to focus on their core business rather than the many technical challenges of high-volume email.

When we talk with companies that rely on a cloud based ESPs to send all their email, we hear some common issues. Because ESPs charge by the email, many companies face continuing high costs for their marketing programs. They’d like to grow those programs, but they face budget and resource constraints. If their programs grow, so do their ESP costs. We’re also seeing dissatisfaction with low inbox delivery rates. Because ESPs typically provide shared IPs to all their customers. That basically means if somebody starts sending spam emails the reputation the IPs will be hit for everybody who is using these IPs.

The common alternatives to working with an ESP are to either outsource to a dedicated infrastructure service that specializes in delivery with the creative and strategy services provided by ESPs, or use in-house infrastructure. Going with a dedicated provider is a smart choice for companies who don’t want to deal with managing hardware and network infrastructure in-house. Especially if you’re working with an ESP and not using much if any of their creative and strategic services, switching to a dedicated cloud offering like MailBrainiers can save you a lot of money. MailBrainiers use tiered pricing, so you’re buffered against steep and surprising price increases if you’re business really takes off. Our quality dedicated services are built on high-grade commercial email platforms, rather than commodity open source servers used by many smaller ESPs, meaning you can rely on consistently excellent performance and uptime. MailBrainiers’ dedicated offerings over ESPs can be substantial, and you still get the advantage of not having to run your own servers and systems.

In the end, it’s not a matter of choosing a dedicated service versus cloud based ESPs but of “choosing right,” or doing what makes the most sense for you and your customers. You may very well find that a mixed environment works best, or you use our dedicated service to handle your transactional messages (purchase receipts, password resets) but stick with your ESP for your marketing messages. Dedicated or in the cloud, a simple rule of thumb when considering options is: which configuration will drive the highest engagement rates and bottom-line value for my organization? Keep that question in mind, and you’re likely to make the right call.

2. Secure Your Sending Reputation

The higher is your sending volume, the more you need to improve your sending reputation among the ISPs that handle most of the incoming email traffic on the Internet. This holds true for major ISPs such as MSN, AOL, Yahoo, AT&T, Gmail, EarthLink, Cox, Bell South etc., as well as smaller local ISPs. A high reputation is critical in getting the majority of your mail safely in the hands of your intended recipients.

To build and maintain a good reputation you need to follow best practices for list acquisition, list hygiene, segmentation and relevancy. This guide focuses on the technical requirements for sending high volumes, but keep in mind that doing so without a solid reputation on your domain and sending IPs is very difficult. From a technical perspective there are a number of bases we need to cover regarding authentication, whitelisting, bounce processing and complaint handling.

  • Authentication

As a reputable sender you will want to associate your IP addresses with your domain using the authentication standards available to you. These include SPF, DomainKeys Identified Mail (DKIM) and Domain-based Message Authentication, Reporting & Conformance (DMARC).

While SPF is purely DNS-based, DKIM require an implementation either during message creation or during relay by the MTA and as a result will impact the maximum throughput of your infrastructure.

DMARC builds on the SPF and DKIM protocols, adding a reporting function that allows senders and receivers to improve and monitor protection of the domain from fraudulent email.

While some recommend selectively signing DKIM only for messages sent to ISPs that are known to check authentication (in order to lower the impact signing has on throughput on a solution that takes a significant performance hit from signing), we recommended that you sign all messages; you never know who is checking for authentication without announcing it.

  • Whitelisting

One benefit of getting on the various whitelists provided by ISPs and reputation providers is that in some cases you can send higher volumes on whitelisted IP addresses than would otherwise be possible. Keep in mind that in most situations whitelisting comes after sending has already begun in order to allow the provider of the whitelist to examine your sending patterns as part of the whitelisting process, so put your best foot forward (and follow it up with consistent behavior).

  • Bounce Processing

One quick way to lose reputation is to repeatedly send mail to invalid email addresses. ISPs will track how many non-existent addresses you send to and throttle you accordingly. Even more seriously, ISPs will occasionally take inactive email addresses and re-activate them as spam traps; any mail sent to the address will immediately get classified as a spam source and will be filtered accordingly.

To prevent this from happening it is necessary to capture and act on the responses sent by the ISPs and unsubscribe those addresses identified as non-existent or inactive, while retaining those with responses that identify users on vacation, with full mailboxes, and other non-fatal conditions. Cloud sending solutions will usually perform this step automatically with varying levels of effectiveness, while other platforms will require a third-party solution.

  • Complaint Handling

In an effort to help senders improve their practices, a number of ISPs have implemented feedback loop (FBL) programs using the abuse reporting format (ARF), the industry standard format for spam reporting.

When a user on a supported ISP clicks the “This Is Spam” button, an automated message is sent to an address defined in advance (when signing up with the ISP for the feedback loop program). By processing these messages and unsubscribing the relevant users, you prevent further reputation damage that may result when sending them future messages. You can also use this feedback to refine your campaign objectives and approach, to provide your customers with the content and offers they are most likely to need or want. The ARF format used by the ISPs makes it relatively straightforward to process feedback loop messages and use them to unsubscribe the users who have complained about your messages. Some sending solutions can handle FBL messages natively while others require separate tools that can open ARF-formatted messages.

3. Scale Your Sending Infrastructure

Several key architectural components come into play to make it possible to send high volumes of email, including network connectivity, server hardware and software. When you’re working with MailBrainiers, then hardware, connectivity and network equipment are all included in the service bundle.

We make sure our service level agreement (SLA) provides for more-than-adequate equipment along with redundant backup.

  • Network Connectivity

Our professional sending operations are based in rented datacenters from USA and Europe, simplifying the provisioning of network connectivity. For example, if we need to send a billion emails per month, we’re talking 2.5 million messages per hour, and we’ll assume a sample message size of 50 kilobytes (51,200 bytes), meaning that we need to send at a rate of 2,500,000 * 51,200 = 128,000,000,000 bytes per hour or 271.2 megabits per second. With this throughput, you will certainly need gigabit-speed networking in the datacenter. We will do the math on your expected throughput, to determine your infrastructure needs. We understand that email has a significant impact on your bottom line so you don’t have to tolerate extended outages.

  • Server Hardware

Moving high volumes of email does not require the purchase of custom server hardware but it does require making a proper investment in hardware. Generally speaking you will be using an infrastructure similar to the one shown in Figure 1.

The Web Based Campaigns Interface queries the database and uses the results to assemble one or more messages, which it relays to the Outbound Mail Servers via Load Distributor ( or load balancer). The Load Balancer distributes messages to the Outbound Mail Servers. The Outbound Mail servers queues the message, performs any necessary manipulations on the message (IP rotations) and then sends it via the Internet to the destination server.

In the event of a delivery failure message or a feedback loop message, the incoming message arrives via the Internet to the Inbound Mail Server (setup on another dedicated server). The Inbound Mail Server performs antivirus/anti-spam scanning and then, in the case of a legitimate message, processes the message and Web based Campaigns Interface updates the subscriber information in the database by querying the Inbound Mail Server.

In a production deployment there can be several variations on this example, typically with multiple servers used on the outbound and inbound roles, with multiple message injectors pushing to the outbound machines and often specialty servers on the inbound side dedicated to processing incoming feedback loop and bounce messages.

To send in very high volumes (say, more than a billion a month), we deploy quality working mail servers with the following features:

  • 2x multi-core, 64-bit processors
  • 16-32GB of RAM
  • 8x15K RPM hard disks
  • Battery-backed RAID-10 controller

The specific details of hardware selection will depend on your actual and expected sending volume and the ability of your specific software to leverage the resources provided.

In addition, our sending software supports IP domain segregation. ISPs pay close attention to the source IP domains of email flowing into their servers. If any domain sends a high rate of mail that looks like spam, or gets flagged as spam by recipients, or contains bad addresses, the ISP will filter traffic from that domain accordingly, or might block all traffic from that domain outright.

If all of your mail comes from a single IP, you run the risk of all of your mail getting blocked. For example, let’s say we have one million messages to send today, and they break down into three groups. The first third is going to addresses that we’re very confident are legitimate because those addresses have been used in the past to send invoices, order confirmations and other transaction-based emails. The second third of the list was generated with confirmed- or double-opt-in tactics, so we’re confident that these won’t be blocked, but not with the same level of certainty as group one. The final third of the address list was built using unconfirmed- or single-opt- in tactics; we need to separate out these addresses because they’re likely to generate a higher number of spam complaints than group one or group two. Given the situation, our sending software could accommodate a single domain for each IP.

Our sending software goes beyond basic message queuing and sending, providing the additional functionality required for a high-volume sender. Here are some other critical features to look for:

  • High Availability

With high-volume sending, we provide you a solution that provides high availability out of the box. If a server goes down, we always have a backup ready for you, so don’t need to worry about any server outages. We provide you an active-active solution that reacts automatically to server failures and keeps the mail flowing.

  • Centralized Management

We provide you a solution that can be easily managed on your terms. In addition, we provide mailing solutions that grows with you.

  • Advanced Reporting

One key to successful sending at high volumes is keeping tabs on how your server is performing and how your mailings are doing. We always monitor what is passing through your server, how quickly messages are moving, whether queues are backed up, how the various ISPs are treating your traffic, all with the ability to drill down on specific source IPs and specific destination ISPs to make sure your emails always reach the intended inbox.

4. Strengthen Your Monitoring Capabilities

When sending high volumes of mail, you just can’t afford to have a “fire and forget” mentality. You need to keep a constant eye on your environment, monitoring multiple key factors to ensure that you can continue to successfully send.

  • Reputation Monitoring

Remember earlier when we said you needed to improve your sending reputation? You also need to maintain your good reputation. To do that you should keep a close eye on the reports produced by our sending software. You need to watch metrics such as bounce rates, FBL hit rates, blacklist hits, transient failures and response rates.

  • Response Monitoring

Keep in mind that you get what you monitor for; if you focus too much on one metric it may improve without helping the big picture. In addition to making sure all the underlying pieces are in place, don’t forget to keep an eye on things where the rubber meets the road. You may be sending at phenomenal rates with great metrics but failing to generate customer actions that lead to revenue. So don’t forget to monitor your response rates.

How MailBrainiers can help you?

MailBrainiers have sourced email infrastructure from some of the most reputed data centers in USA and Europe. We deploy multi homed GBPS networks to make sure you get uninterrupted services 24x7. 

In order to send huge email volumes you need to monitor two things: IP reputation and your domain’s reputation. But what if we tell you that you do not need to monitor the IP reputation any more? At least not for Google, world’s biggest email service provider. (Gmail is currently world’s biggest email provider including the domains powered by Google Apps.)

Do you know the world is moving towards IPv6 technology and so does the ISPs?

We have been hearing from a very long time that the IPv4 address are going to get depleted soon and we will have to start using IPv6 to overcome this situation. Well some of the ISPs have already implemented IPv6 technology in their network infrastructure and Google is one of them.

Among the big four (Google, Yahoo, Microsoft and AOL), only Google has adopted IPv6 technology right now. Microsoft is second in the race and they are going to declare their support to IPv6 soon.

Now what does that mean?

That essentially means that we no longer have to worry about the IP reputation any more.

  • Surprised?
  • Want to know WHY?

Because IPv6 address space is so vast that a single IPv6/64 block comes with a few billion IP addresses (18,446,744,073,709,551,616 IP addresses to be exact). Due to such a large no. of IPs it will become practically impossible for the ISPs to monitor the IP reputations.

We no longer have to monitor the IP reputation. But major concern is how will the ISPs monitor the spam?

ISPs are now going to rely on the domain reputation solely. If you are able to create a good reputation for your domains you will be a winner in email marketing space.

Google is already accepting emails from IPv6 networks and MailBrainiers have adopted the IPv6 technology after Google. That means we longer need to monitor the IP reputations to send emails to Google. Now MailBrainiers can send unlimited emails to Google without need to worry about the sending IP’s reputation. You just need to adopt the best practices for your email campaigns, build great reputation for your domains and you will become a superstar email marketer.

Start Sending!

While by no means an exhaustive list, this should give you a good idea of what’s required in a high-volume sending environment, while keeping your customers happy and engaged. If your company is growing, it pays to see the road ahead, and high-volume sending might be in your future sooner than you think.